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Topic: L36 Engine cam replacement

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L36 Engine cam replacement (1/65)
 9/13/13 12:17pm
rep69
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Suffolk, VA - USA

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1969 convertible 427 4speed


Joined: 7/24/2012
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I own a 1969 427  The cam in the engine is worn and this winter I am going to have to do something with the engine. I know there are a lot of options.  I have owned the car for a year and a half. I have been trying to educate myself on these older engines. The engine is stock.  I am looking for suggestions on how to proceed. Stay with stock flat tappet cam on maybe a roller cam?  Thanks, Bob
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Re: L36 Engine cam replacement (2/65)
 9/13/13 12:40pm
F4GaryGold Member
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Grapevine, TX - USA

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I'd go with a modern cam, roller lifters, and roller rockers.  You wouldn't have to worry about what oil to use and it wouldn't change the appearance of your engine.

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Re: L36 Engine cam replacement (3/65)
 9/13/13 1:15pm
Adams' AppleLifetime Member
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Duncanville, TX - USA

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Flat tappet cams/lifters made today are designed for the low ZZDP content of the oils available, so they will survive much better than the older, original designs. Roller cams are kewl, but require more work and parts to install(and $$$), such as something to keep the cam from "walking" forward, which is usally accomplished with a cam "button", but some require some machining of the block to add a plate to hold the cam in position.
Roller rockers are also kewl, but may not fit under a stock valve cover...especially if you have power brakes.

You can buy/order cams that are copies of the original, older cam profiles, but are made to work with today's oils, or you can bump it up a bit if you want to. Decisions, decisions.....Ermm

Personally, I would go back with a stock type cam, or maybe one with a little more aggressive grind..but that's just me...Thumbs Up

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Re: L36 Engine cam replacement (4/65)
 9/13/13 2:13pm
rep69
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Suffolk, VA - USA

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Thanks for the replies .  I have options, just need to sit down and decide which direction to go in.  I need to talk with the cam manufactuers and maybe get some information from them too.
Re: L36 Engine cam replacement (5/65)
 9/13/13 10:32pm
rod7515Lifetime Member
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Red Lion, PA - USA

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I thought about that for weeks when I did an engine upgrade in mine. I would take the time to talk to your local machine shop that you use and listen to what they recommend. There is a higher cost when going to a roller set up. Might be as much as a thousand dollars more. Depending on what all you decide to upgrade. I wish I would have gone roller cam because todays grinds with roller cams are much more efficient then flat tappet cams in my opinion. I decided to save the money. Not a bad decision but I think the Dodge I am doing now will be roller cam not flat tappet. As mentioned earlier either one will work fine, so you cant make the wrong choice. Just remember if you have headers and you break in a flat tappet cam you need to put manifolds on for the break in. Best of luck Rodney

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Re: L36 Engine cam replacement (6/65)
 9/13/13 11:31pm
rep69
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Thanks for the info. Did not realize the cost difference was so much.  I will continue to gather more advice.     Bob
Re: L36 Engine cam replacement (7/65)
 10/24/13 3:10pm
rep69
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I am still trying to get some answers before I do anything major to the engine. Had one mechanic have the car for 3 weeks and never got to look at it. Different people tell me different things. The mechanic that replaced my valve stem seals told me the cam is worn. Another mechanic says it is probably just the carb.   The car idles good.  On the road is when you notice the missing and surging of the engine, especially at 2,000-2,500 rpms .  Holley double pumper was rebuilt last year. 
Re: L36 Engine cam replacement (8/65)
 10/24/13 5:46pm
nosal1
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Dunedin, FL - USA

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Hello and good afternoon   I have a question relating to the missing at 2000-2500 rpm.Is it a massive miss or subtle miss at those RPM's ?Do you have an OEM points distributor? When a cam takes a hike you general feel it at idle an not above 2000 rpm.It becomes more noticeable at idle. Also,if you still have a OEM points distributor,do you have a condenser that should be attached to the positive side of the coil. That condenser maintains 12 Volts to the coil,and as rpm increases the voltage to dist.decreases to 9.86 volts and would create a slight miss at those RPM's if the condensor is bad..This all is for naught if you don't have a points dist.                Have a great day and good luck.        Sal C

Re: L36 Engine cam replacement (9/65)
 10/25/13 4:07pm
CCasey
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New Albany, OH - USA

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1980 Coupe / Snowcrest White / L48, 350 / Comp Cam / Edelbrock Heads / Cyclone Intake / Holley Carb / Holley Fuel Pump / Patriot Headers / Dual Exhaust / Magnaflow Mufflers / 1964 Coupe / Riverside Red / L76, 327, 365hp


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For whatever it's worth, I installed the following parts to my 1980  L48 engine.  I never had it dyno'd but a couple reputable mechanics estimated that she puts-out about 350 - 375 hp.
 
12-000-8         (Comp Cam) Hydraulic Roller Cam

Duration @ .050: 210 intake; 220 exhaust

Lobe Lift: .3340 intake; .3420 exhaust

                                    Lobe Separation: 112-degrees

                                    Gross Valve Lift: .501 intake; .513 exhaust

                       

853-16                   (Comp Cam) Lifters

2100                (Comp Cam) Timing Set

611-16             (Comp Cam) Valve Locks

740-16             (Comp Cam) Retainers

986-16             (Comp Cam) Valve Springs

1412-16           (Comp Cam) Roller Rockers

201                  (Comp Cam) Wear Plate

202                  (Comp Cam) Cam Button

 

5089                (Edelbrock E-Street) Aluminum Cylinder Heads

                                    2.02-inch intake / 1.60-inch exhaust Valves

                                    64-cc Combustion Chambers

                                    RPM Range: Idle – 5,500

 

0-80770           (Holley Street Avenger) 770-cfm Carburetor

 

12-834             (Holley) 80 GPH Fuel Pump w/ 3/8-inch Fuel Line

 

52010              (Power+Plus) Cyclone+Plus Dual Plane Intake Manifold

 

51-1572           ECC Distributor Cap

 

51-5582           ECC Rotor

 

323236            (Patriot) Ceramic-Coated Tight-Tuck Exhaust Headers

                                    1 5/8-inch Primaries

                                    2 ½-inch Collectors

 

323018            (Corvette Central) 2 ½-inch Aluminum Dual Exhaust

 

323454            (MAGNAFLOW) 2 ½-inch Mufflers



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Re: L36 Engine cam replacement (10/65)
 10/29/13 3:21pm
rep69
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Suffolk, VA - USA

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Thanks for the information. I finally got the news about the cam. One of the lobes is worn down and not allowing the valve to open properly. I will have to consider which direction to go with the replacement.  
Re: L36 Engine cam replacement (11/65)
 11/5/13 12:20pm
rep69
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Suffolk, VA - USA

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The time has come to start with the cam replacement. My mechanic is going to pull the engine and start the process. While the engine is out I am going to have the engine gone through and other items addressed while the engine is out. Take care of everything at one time. Hopefully it all goes smoothly. 
Re: L36 Engine cam replacement (12/65)
 11/5/13 1:18pm
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Duncanville, TX - USA

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#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


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 Good luck! Hope it all comes together nicely with no surprises! Thumbs Up

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Re: L36 Engine cam replacement (13/65)
 11/14/13 11:59pm
rep69
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Suffolk, VA - USA

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1969 convertible 427 4speed


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The engine overhaul process has begun.  While I have the engine out I want to clean up and coat the exhaust maifolds.  Looking for some feedback on what type of coating to use.  Spray can paint them myself or have it done by professional ?

Re: L36 Engine cam replacement (14/65)
 12/17/13 2:25pm
rep69
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Suffolk, VA - USA

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When I bought my 1969 427 390 hp  it was equipped with a Holley Double pumper spread bore carb.  I have been looking at different web sites and reading books and I see that the engine could have been equipped with a Holley or a Rochester q jet carb.   any thoughts? 

Re: L36 Engine cam replacement (15/65)
 12/17/13 5:03pm
nosal1
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Dunedin, FL - USA

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Here is some info you might like..
    The 1969 ZL1 version of the 427 engine was developed primarily for Can-Am racing, where it was very successful in cars like the Chaparral 2F and McLaren M8B. The ZL1 had specifications nearly identical to the production L88 version of the 427, but featured an all-aluminum cylinder block in addition to aluminum cylinder heads, which dropped total engine weight into small block Chevy territory (approx. 575 lb or 261 kg dressed).[citation needed] The engine was also fitted with the new open combustion chamber cylinder heads, a light weight aluminum water pump, a camshaft that was slightly "hotter" than the L88's and a specially tuned aluminum intake manifold. Like the L88, the ZL1 required 103 octane RON (minimum) fuel, used an unshrouded radiator and had poor low speed idle qualities - all of which made the two engines largely unsuitable for street use. [102 octane RON (Sunoco 260) represented the highest octane gasoline sold at common retail stations.]

As impressive as the ZL1 was in its day and despite the "larger than life legends" surrounding it, actual engine dyno tests of a certified production line stock ZL1 revealed 376 SAE net HP, with output swelling to 524 Gross HP with the help of optimal carb. and ignition tuning, open long tube racing headers and with no power sapping engine accessories or air cleaner in place. ZL1 DYNO TEST - COPO CAMARO WEBSITE A second engine dyno test conducted on a second production line stock (but recently rebuilt and partially blueprinted) ZL1 revealed nearly identical figures for the various "Gross" conditions.[7]

Period magazine tests of the ZL1 were quite rare due to the rarity of the engine itself. "High Performance Cars" tested a production line stock but well tuned example and recorded a 13.1 second/110 MPH quarter mile, which correlates quite well with the previously referenced 376 Net HP figure. "Super Stock and Drag Racing Magazine" recorded an 11.62 second/122.15 MPH quarter mile in a ZL1 Camaro that was professionally tuned and driven by drag racing legend Dick Harrell, although that car was also equipped with open long tube S&S equal length headers, drag slicks and minor suspension modifications. Using Patrick Hale's Power/Speed formula, the 122.15 MPH trap speed indicated low 11 second ET potential (e.g. with larger drag slicks) and suggested something on the order of 495 "as installed" HP in that modified configuration. This large difference in power suggests that the OEM exhaust manifolds and exhaust system were highly restrictive in the ZL1 application, as was also the case with the similar L88..Sal C
Re: L36 Engine cam replacement (16/65)
 12/18/13 6:48am
nosal1
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Data you might be interested in having.. Sal C

69 VetteBase 350L46 350L36 427L36/L68 427L71 427L88 427
HP @ RPM300 @ 4800350 @ 5800390 @ 5400400 @ 5400435 @ 5800430 @ 5800
Torque @ RPM380 @ 3200380 @ 3600460 @ 3600460 @ 4000460 @ 4000550 @ 4000
Compression Ratio10.25:111:110.25:110.25:111:112.5:1
Bore & Stroke4.00 x 3.484.00 x 3.484.251 x 3.764.251 x 3.764.251 x 3.764.251 x 3.76
Cylinder BlockCast IronCast IronCast IronCast IronCast IronCast Iron
Main Bearings555555
Valve LiftersHydraulicHydraulicHydraulicHydraulicMechanicalMechanical
Carburetion4bbl Rochester4bbl Rochester4bbl Rochester3x2bbl Holley3x2bbl HolleyLarge 4bbl Holley
Intake ManifoldCast Alloy IronCast Alloy IronAlloy AluminumAlloy AluminumAlloy AluminumAlloy Aluminum
Oil Capacity5qts w/filter5qts w/filter6qts w/filter6qts w/filter6qts w/filter6qts w/filter
ExhaustDual, 2.0"Dual, 2.0"Dual, 2.0"Dual, 2.0"Dual 2.0"Dual 2.0"
Spark PlugsACR44SACR44SACR43NACR43NACR43NACR43XL
 
Re: L36 Engine cam replacement (17/65)
 12/24/13 12:45pm
rep69
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Suffolk, VA - USA

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Thanks for the info
Re: L36 Engine cam replacement (18/65)
 12/27/13 2:25pm
SteveC
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, - Canada

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Curious which cam you decided to go with?
 
I have the same engine (1969 L36) and am in the process of reassembling my engine after a stock rebuild. I ordered a Comp Cams Magnum 280H and as I try to decide if the stock springs are going to work with this cam and it's 0.520 valve lift, I am having second thoughts. I have new lifters, pushrods, timing set and the heads were done with new bronze guide inserts, valves, stem seals, etc. The existing cam is OK according to bench measurements of lift but I am tempted to give it a bit of a lopey idle...
 
BTW the carb was originally a Rochester Quadrajet 7029215 EH. They are extremely difficult to find an original because they were a one year carb and only used a few cars including the Corvette L36 with Manual Transmission. There are many carbs that are very similar and it is not too hard to have one rebuilt with the correct metering/calibration to match the 7029215 EH.
 
Photo below is current state of assembly with my son doing all the hard work and me supervising, as it should be.
 


|UPDATED|12/27/2013 11:25:45 AM (AZT)|/UPDATED|


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Re: L36 Engine cam replacement (19/65)
 1/9/14 4:25pm
rep69
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Suffolk, VA - USA

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Thanks for the information. My engine is still being rebuilt. Hopefully next week I will get it back from machine shop??  When I bought the car it had the Holley carb. The original rochester is long gone. It would have been nice to have it.
Re: L36 Engine cam replacement (20/65)
 1/24/14 11:21pm
rep69
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Suffolk, VA - USA

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My L36  engine is finally ready to go back in the car.  New Comp cam and rocker arms and timing chain. new pistons.  The machine shop went through the entire engine and they did a great job. The aluminum manifold needed some work. The mechainic explained how important it is to keep a check on the antifreeze condition. My manifold had some pitting and small cracks.  He told me to check the PH level of the antifreeze. I will get a PH test kit and monitor my system. 
Re: L36 Engine cam replacement (21/65)
 1/24/14 11:44pm
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 Clap  NICE! Keep us updated when ya get it installed, and fired up! Thumbs Up

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Re: L36 Engine cam replacement (22/65)
 2/1/14 11:49am
rep69
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Suffolk, VA - USA

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small set back on the install of engine. I want to put the original shifter back in the car but had to order a mounting plate for the transmission. There are many other things to do, install new vacuum hoses  and replace the power steering ram and control valve and hoses.

Re: L36 Engine cam replacement (23/65)
 2/1/14 2:13pm
rep69
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Suffolk, VA - USA

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I am interested in knowing if anyone is using a lead substitute in their fuel tanks.  I know there are probabaly a lot of different ideas on this subject, but I would like to know what people are doing. 
Re: L36 Engine cam replacement (24/65)
 2/1/14 7:35pm
F4GaryGold Member
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rep69 said: I am interested in knowing if anyone is using a lead substitute in their fuel tanks.  I know there are probabaly a lot of different ideas on this subject, but I would like to know what people are doing. 


You don't need lead unless you are operation under a continuous load or high rpm (like a boat or airplane).


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Re: L36 Engine cam replacement (25/65)
 2/1/14 10:44pm
rep69
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Thanks for the info..
Re: L36 Engine cam replacement (26/65)
 2/2/14 2:47am
HighDesertDave
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I had stainless exhaust valve seats installed in an older V8 I just finished. Your machine shop should have suggested that this would be the appropriate way to run our unleaded fuels with iron heads. The iron valve seats will wear much faster than originally intended with unleaded fuel. The lead acts as a cushion when the valve slams down. It also cools the valve and seat. Its not a lot dough and your good to go for many many miles.

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Re: L36 Engine cam replacement (27/65)
 2/27/14 12:00pm
rep69
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Engine is almost ready to to be started up for the first time. There have been some delays in getting everything put back together. This was my first time dealing with a large project.
Re: L36 Engine cam replacement (28/65)
 3/6/14 11:31pm
rep69
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A small set back today. When we started the engine for the first time, the new rocker arms are hitting the valve covers . Not sure what we are going to do. The car has some aftermarket chrome covers that were installed before I bought the car. Hopefully I can find a fix and then be able to run the engine enough to break in the new cam.
Re: L36 Engine cam replacement (29/65)
 3/7/14 12:12am
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Did you put roller rockers on it, or are they stock? If they're the stock rockers, there's no reason for them to be hitting on the valve covers...especially if they weren't hitting before, with the same covers. Do the valve covers have the drippers on the inside? Perhaps one or more of the drippers got bent? 

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Re: L36 Engine cam replacement (30/65)
 3/7/14 7:00am
nosal1
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Good Morning All, As Mr Adams has stated that if the Roller Rockers are OEM GM rockers,then they should be OK,however if they are aftermarket aluminum and the Valve covers are the normal size,then you will have them banging on the covers.The builder of the engine had not started the engine to notice the "tapping" of the lifters.  Two possible fix's, one is to change to tall valve covers,which they sell on Ebay etc.,and the second way is to buy Fel pro's thick valve cover gaskets (about 7/16" instead of 5/16"),I can not remember the part # and most parts store look at you like you are nuts.

I will try to find the part # for the gaskets later today.
Good luck and all have a great day..        Sal C
Re: L36 Engine cam replacement (31/65)
 3/7/14 11:44am
rep69
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Hey. Thanks for the info. I will check with the machine shop today and talk with my mechanic who installed the engine. They put a comp cam and comp magmum  rocker arms. I will look at the paper work again to confirm.  I do know the machine shop primed the engine before it was installed. Make sure the oil was circulated and checked the oil psi.  On the first start up of the engine after it was installed is when the mechanic heard the tapping.  I will tell him about the different gaskets .  He probably knows.  This all happened last night. 
Re: L36 Engine cam replacement (32/65)
 3/7/14 12:05pm
nosal1
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FYI All      I have used the following valve cover gaskets with success of raising the OEM short valve covers and aftermarket short valve covers to move valve cover up away from aftermarket roller rockers.They are as follows:

                                                      Fel-Pro      #1603 5/16" thick
                                                      PRC  VC 1603        5/16"    "     Procomp
                                                       AFR  1604       do not have thickness

Generally there is no problem with OEM Chevy Roller Rockers




Re: L36 Engine cam replacement (33/65)
 3/7/14 12:10pm
nosal1
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Correction of earlier message measurements should read  

7/32" not 7/16" as the gaskets I am suggesting is Fel Pro and or PRC  VC 1603 both of which are 5/16"...Sal C 

Re: L36 Engine cam replacement (34/65)
 3/10/14 11:19am
rep69
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New gaskets ordered. Hopefully this fixes the problem.  Some minor tuning and tweaking of eveything and I should be good to go. Thanks to eveyone that commented. This was my first time at a major project on the car.

Re: L36 Engine cam replacement (35/65)
 3/10/14 12:31pm
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Duncanville, TX - USA

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#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


Joined: 11/8/2003
Posts: 20126

 Excellent!
You never really said what Cam you went with, or what type of rocker arms. Just curious....


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Re: L36 Engine cam replacement (36/65)
 3/10/14 8:33pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

A COMP flat tappet cam was installed with COMP magnum tip rocker arms

Re: L36 Engine cam replacement (37/65)
 3/13/14 8:30pm
rep69
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Suffolk, VA - USA

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1969 convertible 427 4speed


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I finally got the info on the parts that were installed. 1 MK1099A engine overhaul kit..040 piston and ring set.  280H comp cam kit Comp magnum roller tip rockers.

Re: L36 Engine cam replacement (38/65)
 3/28/14 9:42am
rep69
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Suffolk, VA - USA

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1969 convertible 427 4speed


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Almost got the car ready to go. New gaskets installed. Engine sounds great. Need to do some small adjustments on the exhaust pipes.  Now that everyhing is back together, the wiper door will not operate properly. When you start the car the door opens slightly and it will not go down.  Trying to trace the system out and find the problem.  
Re: L36 Engine cam replacement (39/65)
 3/28/14 1:14pm
Adams' AppleLifetime Member
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Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


Joined: 11/8/2003
Posts: 20126

That 280 is a nice cam. Thumbs Up
Wiper door popping up like that is usually due to low/no vacuum. Make sure the vacuum is connected properly to the engine source, and that you have the check valve in the line, and facing the correct direction. Single line side to the engine vac source, and on the dual line side, one line to the firewall/interior, and the other goes to the vacuum reservoir/tank, on the driver side fenderwell area.
Also...make sure the over-ride switch and push/pull knobs under the dash are all in the proper position. Thumbs Up


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Re: L36 Engine cam replacement (40/65)
 3/28/14 8:17pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

Thanks for all the info. Yeah, I have a couple of GM mechanics helping me trace out the system. I am not the original owner, and over the years people have bypassed some of the vacuum lines.  Not the simpliest system!! 
Re: L36 Engine cam replacement (41/65)
 3/29/14 11:48pm
JohnRR
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Dr. Rebuild has some nice vacuum line kits and an excellent printed instruction/trouble shooting guide.

John



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1973 BB 4-Speed Coupe Project Car
2009 Z06 Mostly Stock
Re: L36 Engine cam replacement (42/65)
 3/30/14 10:40pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

Thank you for the info. I will look them up on the computer. 
Re: L36 Engine cam replacement (43/65)
 4/17/14 8:59pm
rep69
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Suffolk, VA - USA

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1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

Today I finally was able to drive the car for the first time since the engine overhaul.  It has been a long process, but it was worth it. Engine sounds great. I am going to drive it around locally to put some miles on the engine. Then I can change the oil and hopefully be good to go.  I am still having the issue with the wiper door opening up after you shut down the engine. I am going to have another corvette mechanic take a look and hopefully it is something simple. 

Re: L36 Engine cam replacement (44/65)
 4/18/14 1:24pm
F4GaryGold Member
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Grapevine, TX - USA

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1972 LT-1 convertible with factory air.


Joined: 8/26/2006
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rep69 said: My L36  engine is finally ready to go back in the car.  New Comp cam and rocker arms and timing chain. new pistons.  The machine shop went through the entire engine and they did a great job. The aluminum manifold needed some work. The mechainic explained how important it is to keep a check on the antifreeze condition. My manifold had some pitting and small cracks.  He told me to check the PH level of the antifreeze. I will get a PH test kit and monitor my system. 


Only use distilled water when mixing your coolant.


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Re: L36 Engine cam replacement (45/65)
 4/20/14 4:54pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

Thanks for the info.   I took the car out for its first long drive today. Highway and local driving. She is running good except for when I turn the air conditioning on the car will not idle when you come to a stop light. The engine will flood out and die. I have to push the gas pedal to the floor and hold it and then crank the engine to get it to start.  Any suggestions?  simple adjustment of the floats?  a/c compressor belt too tight?  I have a Holley 4150 double pumper carb.  The carb was rebuilt last year. It was working good before the engine overhaul.
Re: L36 Engine cam replacement (46/65)
 4/21/14 12:17am
JohnRR
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The float adjustment on a Holley is about as simple as it gets.  Have the engine fully warmed up and sitting on a level surface.  Remove the air cleaner assembly.  Place a cotton rag along the passenger side of the carb to catch the drips that are going to come out of the sight plug.  Have a wide-blade screwdriver and a 5/8 box wrench available.  Start it up and let it idle.  Remove the fat screw plug on the primary side of the carb.  If gas begins running out, then the float is too high.  Place the 5/8 wrench on the float adjustment nut, and then loosen the slotted lock screw on top.  Turn the hex nut clockwise to lower the float until gas just barely drips out the side hole.  Hold the wrench still and lock the adjustment with the slotted screw on top.  Replace the side plug.  Repeat on the secondary side and you're done.

Do you have the distributor vacuum advance on full manifold vacuum?

Lastly, you can get a throttle stop solenoid that is activated when the A/C comes on and it will increase the throttle position a little.

John




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1973 BB 4-Speed Coupe Project Car
2009 Z06 Mostly Stock
Re: L36 Engine cam replacement (47/65)
 4/21/14 10:41am
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

Thanks for theh info.  I am always trying to learn something about fixing my own equipment, but I am going to take the car back to the mechanic who installed the engine  and have him do the adjustments to the carb. 
Re: L36 Engine cam replacement (48/65)
 4/24/14 9:06pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

I was told by my mechanic that I need to let the engine break in some more before he adjusts the carb. The engine idles good and runs good with the air conditioning off.  I am not a mechanic but it seems that the carb can be adjusted anytime??
Re: L36 Engine cam replacement (49/65)
 4/25/14 12:50pm
nosal1
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Dunedin, FL - USA

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1980 Corvette Torch Red with Gold metallic 370HP/350 CU.IN.Turbo 350 w/shift kit.Originally CA.Car with 305 CU.IN.


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Posts: 262

Good Afternoon,  The mech is partially right about setting the carb.

It is always best to make the adjustments when engine has "loosened up a bit",however the difference is minimal.He can or you can adjust now and the recheck when you change oil/filter.   Now as far as the idle reduction when you turn on the AC.  You will have to purchase a idle control solenoid that normally mounts on front of carb and is electrical charged when AC is turned on and runs.  I know you can get one though Edelbrock for Edelbrock carbs along with one for a Q-Jet carbs,however never looked for one for a Holley carb (not a fan of Holley's,great carb for racing not daily driver etc.) and not sure there is one for that carb. It is a solenoid, that when you wire it into power source (green wire) for compressor,it will send a throttle pin to boost throttle linkage thereby increasing idle to compensate for the AC drag on engine.  I hope this may help.Take care and have a great day..
Sal C             no1sal
Re: L36 Engine cam replacement (50/65)
 4/26/14 10:17pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

Ok I will drive the car and put some more miles on the engine. Before I had the engine overhauled, it would idle good with the a/c on of off. When I bought the car, it had the holley carb. I am happy with the holley, hopefully it just needs some fine tuning. I understand that my engine probably came from the factory with a rochester q-jet.  The L-36  390 hp 427 on an early 1969 car. 
Re: L36 Engine cam replacement (51/65)
 6/3/14 4:44pm
rep69
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Suffolk, VA - USA

Vette(s):
1969 convertible 427 4speed


Joined: 7/24/2012
Posts: 134

I was going to hold off on getting a paint job, but last month the paint shop was slow with work so I bit the bullet and had the car repainted.  The car has been in the paint shop for a month!!  This is my first time dealing with a repaint of a corvette. I guess this is typical? The car is almost finished. I will try to post some pictures of the new monza red paint  

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