Hey All,
Will a TPI setup fit under the stock hood of my '81? If not, what is required to make it work?
Or am I better off putting a Throttle Body Injection on it? For example a Holley Commander 950 unit. Thanks in advance.
Sarge

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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.

Lots of folks have done this swap w/no fit problems at all. I currently have a similar intake that is substantially taller than the stock TPI under the hood of my '73. Are you thinking of using the stock 730 computer or an aftermarket like the Accel unit? There are advantages and disadvantages to both. I'm currently using the Accel 6.0 DFI computer. I had to rip out my dash all the way to the firewall to route the wiring harness behind it and mount the computer behind passenger side glove pockets. The newer Accel or Speed Pro computers, I heve heard, can mount under the hood like the stock computer. This would be a MAJOR plus for you. If you haven't begun the search for parts and/or knowledge you might try Rich at Cruzin Performance ( http://www.cruzinperformance.com/ ) I almost bought my intake from him. Wish I had now. If you have questions feel free to e-mail me. I'm no guru by any stretch but I'll share what I have learned.

good luck
dr

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'73 coupe,ZZ4, S&P Tunnel Ram intake, Accel 6.0 DFI, 6-link rear susp, Stewart Stage III wtr pump /// '96 LT4 CE...bone stock

Thanks David,
I'm not sure if I'm going to use a stock or aftermarket unit yet. I was just looking through one of my magazines yesterday, and noticed that Scoggin-Dickey Parts Center has a Tuned Port manifold available for Vortec heads. Which is what I have on my engine. And as you probably know, aftermarket manifolds/ injection units for Vortec heads are limited. So after seeing this, it kind of re-sparked my interest in TPI.
I will check out the web site you mentioned. Thanks again! If you have any pics of your TPI/engine compartment, I'd would like to see them. If you have time. My e-mail address is SARGE81vettenut@aol.com

Thanks, Sarge

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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.

Hi Sarge,

I did it to my '80. The TPI will fit no problem. I used a K&N filter over the front of the TPI and I also used the commander 950 ECM. The cabling was long enough and the ECM small enough to mount the ECM on the trans tunnel below the heater controls. I would highly recommend the Holley ECM. If you ever decide to modify the engine (which probably won't be long...) It can be setup and retuned on the fly via laptop from the passenger's seat. By the time you buy 2 "performance" chips, the ECM is paid for. Of course a big assumption is that you have access to a laptop.

If you have any questions, drop me a line...

Greg.
GSelvenis@echoes.net

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Greg S. '80 Frost Beige 383 w/ TPIS MiniRAM AFR 190's Holley Commander ECM 700R4 w/ 3.73's

Thanks David, for the pics!
I will be sending you some pics of the '81 soon. I'm still figuring out how to work digital cameras and computers.


Also... Thank you Greg for the info! I didn't know that the Holley ECM would work with TPI. That is so cool. I will probably start gathering parts over the winter months. Did you use a stock GM TPI manifold and runners or aftermarket? As I do start to get into this project, I will probably be "bugging" you guys for more info. I hope you don't mind.

Lastly...does anybody know how difficult it is to removing the old computer harness out of an '81? I removed all engine harness, but the chassis harness looks like it is tangled in with some of the regular harness. Or should I leave it along? Thanks! Sarge aka Darryl

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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.

I'm going to be using an Edelbrock 3550 EFI unit on my big block. I like it because you do not need a lap top to make any adjustments and it has three memory settings so you can change from strip to street to economy (turnpike) on the fly. It comes with a hand-held unit that you keep in the cockpit with you. I know they make these for a small block also, I think the number is 3500. I WILL have to change my hood to an L88 style for clearance.

Glenn:

Is that a TB or Port injected? What Fuel pressure does it run at?

dr

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'73 coupe,ZZ4, S&P Tunnel Ram intake, Accel 6.0 DFI, 6-link rear susp, Stewart Stage III wtr pump /// '96 LT4 CE...bone stock

It is "Multi Point " so I guess that translates into port. The fuel pump is rated at 260 pounds per hour ( 50.75 psi ) and the supplied injectors are 20 degree spray with high resistance windings that flow 28 pounds per hour (50.75 psi ).

Oh Man....now I got more choices. What did I get myself into. Now I got a lot of research to do.
lol
Thanks for the input guys, Sarge

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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.

Sarge,
I did not do much homework when I decided on the Edelbrock 3550 unit. Actually, I did not do any homework. I read about it and decided I liked the fact you do not need a laptop and it has "pre-sets" that are stored in memory. This unit also has a rev limiter, but I do not know if that is a feature unique to this unit or not. it will also flow 1000 cfm of air and due to it's design I do not believe that can be changed ( something I have to look at when I get it back from the machine shop ). The MAJOR disadvantage to this unit is price. It is VERY expensive, at least I think it is......I bought it from Summit and paid $2265.00 (Edelbrock wants over $2900 direct from them ). I believe the small block units are between $1600 - $1800 but don't quote me.
Anyway, give Edelbrock a call or drop them an e-mail and ask for the install manual and the owners manual. They sent mine at no cost and I learned a lot from it. The kit also comes with an internal rebuild kit for "mechanical" distributors. Mallory makes a direct drop in replacment that is designed to work with the Edelbrock unit for $285.00. If you decide to go with the Edelbrock, let me know and I will dig up the Mallory part number for you.
One more thing. If you decide not to use the Edelbrock cam, you just send them the .050 spec from the cam you want to use and they will burn the ECU chip to match your cam profile. In my case, I am using a comp cams X-treme energy ( street ) 1800-5800 rpm ( if I decide to change gearing later on, I will move up to the next larger cam to make better power up to around 6500 ). I was going to use the recommended Edelbrock cam but the speed shops I am working with both recommended the comp cam instead. If you change cams at a later date, it will cost you to get another ECU chip programmed. Being able to get the correct chip and not something that is "close enough" or "generic" is the key to the whole shooting match.
The whole set-up just seems to be much more professional. Edelbrock seems to have this whole process figured out and are ready with any future fixes so you don't have to tear out your hair with a "cobbled together " set up.
Good luck with your decision.

glenns, That is some very helpful info. Thank you. The Edelbrock system seems like it would simplify things quite a bit. I will be talking with Edelbrock soon for more technical info.

Sarge

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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.

I am thinking of switching to fuel injection as well. Presently I have a 383 stroker installed with a 750 Holley and original Torquer intake. I have a comp cam extreme cam but this setup is giving me a real flat spot with not a lot of torque from 2500 - 3800 rpm. I would like any suggestions as to which fuel injection system to go with. Also have an MSD6AL with Blaster 2 coil, original distributor with the Pertronix 2.

The Edelbrock 3550 comes with "matched" parts for your ignition system ( distributor and amplifier ) so if you are really happy with the ignition you have, you may not want to use the Edelbrock cause there will be no gaurante they will function together to give best performance or best fuel economy. You could always drop them an e-mail to the EFI techs and ask them, they had no problem at all telling me I did not NEED to use an Edelbrock cam and have no problem burning a new ECU for the Compcams.