Hi guys. Nice board you got here. Well let me get to this question now. I recently bout an '87 Iroc with a 305 TPI in it. The car is bone stock. I recently pulled my 383 out of my '81 Z and plan on putting it in the Iroc. My question is what kind of injectors/computer chips/knock sensors & stuff like that will i need to do this?

Bare with me because i am a Carb guy & don't know much about TPI. I have been reading up & saw that stock 305's came with 18lbs/hr injectors, 350's with 24lbs. So i am figuring 30lbs would be ok for me....

Here is the motor specs:
-383(5.7 rod) stroker with .100" dome KB pistons
-11.5:1 with 64cc Vortec heads & .45 thou gasket
-Comp XE284 hydraulic Flat Tappet cam (.507/.510" lift)
-MSD Pro-billit Distributor
-Holley Strip Annihilator Ignition w/ Lasershot coil

Plz help me out because if it's too much $$$ i will just CARB the sucker!

Thanks.........Carm

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383 stroker, 11.5:1, Vortec heads, Comp XE284, Edelbrock RPM, MSD Distributor, Holley Strip Annihilator

 

305s had 19# injectors stock, and 350s had 22# injectors stock.

You can swap the TPI over to your 383 but it will be involved. I would use at least 30# injectors so you have room to grow. Be prepared to lose some higher RPM grunt over the current carb setup, and you'll want to invest in a high flow intake base and runners, and port the plenum to minimize the choking effect. The other things you'll want to start with are a 350 knock sensor and the PROM from a 350, although you'll definitely have to get a custom PROM made or learn to program your own.

Also, you have Vortec heads and therefore you will not be able to use the stock TPI baseplate, and will have to get one made for Vortec heads from Scoggin-Dickey performance.

So, the project is pretty involved and depends on how bad you want to switch to TPI. With a 383 Vortec setup, you'd probably be better off financially sticking with the carb, and make more horsepower too.

Welcome to the board !

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1990 IROC 350
Mods: Too busy trying to make it run right to mod it.
Airfoil, Dynomax cat-back, MSD coil, 180 t-stat, Bald Eagle tires,
Hypertech fan switch, Accel 23# injectors, Holley module, ported plenum,
Ported Daytona Yellow stock base, Moroso valve covers, other stuff,
Streetdampr, Ruger P95DC, hot wife, new oil filter, !cats, !TBC, !AIR.
18.0 @ 85MPH since I'm one big-a$$ MF
"It's better to have and not need than to need and not have."

 

ok well let's say i don't use the Vortec heads & go with some WP Sportsman II's or something?

The problem i am having is that every moron around here is saying i will have to buy a new computer?

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383 stroker, 11.5:1, Vortec heads, Comp XE284, Edelbrock RPM, MSD Distributor, Holley Strip Annihilator

 

HELP!!!!!!!! I am so lost with this FI stuff!!!! I now understand that i may need a different intake. I was looking @ someintakes by WEIAND and saw that they are designed for "port FI". This is TPI right?

Well anyways, they work 2000-6000 rpm (#9901-101-1)

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383 stroker, 11.5:1, Vortec heads, Comp XE284, Edelbrock RPM, MSD Distributor, Holley Strip Annihilator

 

No, you won't need a new ECM, just a new PROM ($40) from a 350 and some PROM tuning equipment or a custom one ($300 or so). You will also need the knock sensor out of a 350 and some bigger fuel injectors than those you have for the 305.

The only aftermarket intakes I'm aware of that will work with generation I SBC heads are made by TPIS, Edelbrock and Accel. These are compatible with the TPI setup and all it's sensors and vacuum lines, coolant lines, etc. LT1 and Vortec engines are different animals.

For that 383, however, you may want to look into the Miniram, which is an LT1 style intake made to work with your engine (with heads other than Vortec). It will provide much better higher RPM breathing than even an oversized aftermarket TPI setup. You can then use all the sensors, wire harness, computer, etc. from the 305 that you currently have. This intake manifold/plenum is offered by TPIS as well. Their website is www.tpis.com, I think.

Am I making any sense?

 

Also, "Port Fuel Injection" is just the type of fuel delivery system. It simply means one injector per intake port, and therefore there are literally hundreds of different port fuel injection designs on everything from Chevys to ricers. Tuned Port Injection is GM's moniker for that specific design used on 3rd generation Camaros, and therefore everything that says "for port fuel injection" will NOT work with GM TPI systems. The LT1, the LS1 and many other engines are also port fuel injected, but are not called "TPI" by GM. They do not use the same intake manifolds. Does this clear things up?

 

Yea man thanks! That just made everything alot easier!!!!

Ok now this is what the prob is....i already have a Edelbrock RPM intake and Holley Street Avenger carb, MSD billet distributor, Holley Strip Annihilator ignition!

I bought the car with TPI & that's why i want to use it. Can't buy another injection system cause not enough $$$. This is why i want to stick with pretty much the stock TPI stuff. I know it won't breathe alot but it will be much better for me @ the moment. Enlargening the intake ports & maybe getting some factory 350 TPI heads & sending them out to get done is what i should do? I need performance but mostly driveablility @ the moment. I know the throttle response & stuff will be much better to my liking than the carb setup right now.

Also i need to know if my cam is too big!

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383 stroker, 11.5:1, Vortec heads, Comp XE284, Edelbrock RPM, MSD Distributor, Holley Strip Annihilator

 

Hey man I dont think you will have a problem with the tpi a lot of us have or have had 383 in our tpi cars most 383 engines are low rpm power.As for the vortec heads keep them if you just want to get buy for know I can tell you how to make it work if you know a good welder the mod is easy thair are a few cars on this board with stock intakes that I adapted to work with those heads and I have heard nothing but good from them. but you do have a 383 so I would consider that mod a temp fix I would definitly get at least a set of 22lb injectors from a 350 and an adj fuel reg. your bigest problem is going to be the chip its not going to run wel with a stock chip and if you dont plan on doing every thing at once i sugest burning your own it will cost as much as one cutom chip for the equipment to do it and the prom board has lots of info to help get you going.
Just so you know their is a group purches going on now for the sdpc vortec tpi intake you may whant to get in on that for the price of a difrent set of heads you could have the tpi intake you need and still have the vortec heads.just so you know my car is a 355 with the fast burn heads and it has the home made intake on it now and it does fine but Im going to get the sdpc tpi base to try and get a little more power from her.

 

TTT

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383 stroker, 11.5:1, Vortec heads, Comp XE284, Edelbrock RPM, MSD Distributor, Holley Strip Annihilator

 

I forgot this before your cam the lift shouldnot be a problem I have the lt4 hot cam 525 lift I think the bigest factor with the cam is lob separation the tpi like 112-114 I belive if you do a serch on cams you will find this but I think that is how it goes but you may want to read a few other posts before you take my word on it.