hi all,

What size intake and exhaust valves are in a 1978 with the 180hp engine? I want to put a cam, intake manifold, carb and was not sure if i wanted to put a set of heads with 202 valves? or what cam,intake,carb set-up to put on.

thanks

pete k

1978 auto

I'm not 100% sure about the valve size.  I can tell you that aftermarket Street and Street Stip  heads use 2.02, 2.08 on the intake side and a 1.5 or 1.6 on the exhaust.  Some of the small block race heads are starting to use a 2.100.

Stock I would say they have the commonly used 1.94 intake and 1.5 exhaust.

Don't le the side of the valve fool you.  Vortec heads use a 1.94 and 1.5 exhaust.  Flow is greatly affected by port design and the back side of the valve itself.  Thats the reason for the 3 angle valve job that most people get on their heads.  It greatly improves the flow. 

For a decent street engine with a mild cam a decent intake, cam and some head port work and the 3 angle valve job can get you some pretty good gains for little cash outlay.  Might want to mill the heads down for a slight increase in compression.  I think you can probably get your engine into the 275 to 320 HP range, a 35% to 43% increase in power. 

On the other hand if you have to pop the heads off the engine and your not one that has to be 100% correct then the time might be right to go with aftermarket heads.  It also might be a good time to just look at buying a complete topend kit from anyone of the companies that are offering them.  Dart, Trick Flow, Holley, Edelbrock, World are just a few offering kits.

stock your car had 1.94 Intake  and 1.50 Exhaust and a 75.47cc chamber

the 220 horse had 2.02 and 1.60... in the same head casting

Cam size is the biggest black art of all. A cam with a max of 210-214 degrees of duration at .050" will have a smooth idle quality and create good vacuum of about 16-17", and not affect power brakes. A cam with 215 or greater degrees of duration at .050" will have a fair idle with some lope, and MAY require a vacuum tank to keep the power binders working ok. A cam with 225 to 240 degrees of duration at .050" will have a choppy idle, low manifold vacuum and not operate power brakes. Any thing much bigger would be a race type cam. The standard for cam duration in the industry is the duration measured at .050" of lift. Keep that in mind. The biggest street cam I would use is somewhere in the area of 215 to 220 degrees at .050. The milage would be acceptiable and the power gain would be good. I would pick something like a Comp cams 265 dual energy. It has good mid range, noticable idle, works with stock converter. works with stock exhaust and stock intake. The Comp cams 270 is also a good choice, has a rough idle and the largest cam you should use with a stock converter. It should have headers and intake mods.  I use to work with a company that owned Erson cams and this is what I have learned there.

I just bought a VooDoo cam #60102.   Duration 262/268,  Duration @ .050 219/227,  Gross lift 468/489,  RPM range 1500, 5800.

I also have new lifters and springs.  I won't install it until the weather warms up a bit.   I expect a very slight lope, and decent vacuum.  I should be able to run my stock converter. My car is a stock 75 L-48, 165 Hp (wimpy version). I may install an intake as well.  I'm leaving the heads stock, except for a bit of shaving, and I will install dual exhaust. Bought it from Holley with some advice from AfterShark. (Thanks) It sounds like it's in line with Pumps recommendations as well.

I let everyone know how it works out.  Man I want spring to come.  I got some work to do!

hey matt...  i was considering a voodoo 268/276 for BBC but they are only available in hydraulic..  are they planning to offer one for roller hydraulic

its not worth chaning from my comp magnum 270H without getting roller also

I should say however that when our cam designer came on board we did launch some new bbc solid roller cams into our line back in 2004.  Two of my favorites are 502A1 AND 502A2.

I believe there is a cam supplement on the Lunati website.

FYI, our cam designer was the designer of comps High Energy cams, among many other credentials.  So he know what he is doing and how to make power. 

[QUOTE=After Shark]There is a hugh investment to do these new cams.  Since every aspect of this cam is new ground in design and technology that was engineered into the lobe profiles. None of the new Voodoo lobe designs will work on our current cam cores.  This means we had to purchase new forgings for every new Voodoo Cam.  So everything is new about these cams.  You can only image the time, energy and money we have put into this new line of cams.  We launched the hyd flt tappets first as this is the largest part of the market.  Expect solid lifter cams out this year. and I can't really don't have any details on the roller stuff.  [/QUOTE]

well maybe by the time im ready to put the body back on youll have roller hydraulic..  Id really rather do it while the engine is accessible..  once the body is back on..  ill be sticking with the comp if i havent changed it by then.

i have pushed your voodoo products down at the speedshop i work at, I really like dual plane cams..  and you have a great offering..  thanks for the info..