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Discussion Starter #1 (Edited)
I have a 92 chevy 350 cid ( original throttle body truck engine )
I would still love to build a turbo motor , but finacially its not in the plan .

So i have this motor , a tpi manifold .

I am thinking of utilizing the manifold and computer system for my 70 chevy pick up . I am going to go threw the engine and would like some fun oppionons on how YOU would build it for the applications .

Here are my paramiters
Towing the boat
gasmilage
I don't want it to be a slouch .

Having owned a 92 camero z-28 -that motor always impressed me, and i was able to pull 24 mpg in it . I would like to improve on that senerio ( z28)
What compression / cam and fuel pressures along with programing would you use ? I am/was planning on running a camero computer and wiring harness for a manual set up !

my truck is a 70 with three speed 1:1 finail ration / 3:07 gears / 30" tires Help me out with some senerios !
 

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A lot of options, just depends on $$$.

First issue I see, is the towing part along with those rear gears. Youch !
 

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Discussion Starter #3
A lot of options, just depends on $$$.

First issue I see, is the towing part along with those rear gears. Youch !
I know- but these lil flatbottoms don't weigh nothing :)
 

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I know- but these lil flatbottoms don't weigh nothing :)
I used to tow with a 350 single 500cfm carb, crate motor,3:07 gear's , the bed FULL of camping stuff, my hydro, and the girl friend,, had 245-60 -15 tire's , about 26" tire's though ,,towed fine,,, ...........Eric
 

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Chris, Your truck weighs twice as much as your Camaro did and with those tall tires and no gear, you can throw your around town gas mileage and power out the window.
The GM TPI setup is garbage (and that's being nice). You would get better performance out of a Performer RPM manifold and a 750 carb.
For a budget dealio I would run the Vortec heads, 9.5 compression, a nice Hydrolic roller cam in the .485 range with about 225 @ .50 on the durration and a 110 lobe cnt. Performer RPM Air Gap and a 750 Holley.
I would then install an 11 inch 2,200 converter and a set of 3.73's in the rearend.
Headers, 2.5 exhaust and your done.
 

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Sorry to disrupt this thread BUTT. Someone here needs to change his avatar. Are you catching my drift SCOTT? Is that a diaper? Must be cold as you have no package. Oh ya. Did you get treated for them warts yet?
 

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Sorry to disrupt this thread BUTT. Someone here needs to change his avatar. Are you catching my drift SCOTT? Is that a diaper? Must be cold as you have no package. Oh ya. Did you get treated for them warts yet?
That's not me in the pic. It's a friend of mine and I am swinging from his nuts. You just can't tell in the pic.
 

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X's 2 0n the Vortec heads

Chris, Your truck weighs twice as much as your Camaro did and with those tall tires and no gear, you can throw your around town gas mileage and power out the window.
The GM TPI setup is garbage (and that's being nice). You would get better performance out of a Performer RPM manifold and a 750 carb.
For a budget dealio I would run the Vortec heads, 9.5 compression, a nice Hydrolic roller cam in the .485 range with about 225 @ .50 on the durration and a 110 lobe cnt. Performer RPM Air Gap and a 750 Holley.
I would then install an 11 inch 2,200 converter and a set of 3.73's in the rearend.
Headers, 2.5 exhaust and your done.
I built a 400 sbc for my Suburban, Vortec heads, new from Summit. The RPM Air Gap manifold, 750 Holley. Now, I bought Dished pistons to keep compression down. This is a 4X4 Suburban tow vehicle.There is a complete build in the book"How to build BIG-INCH Chevy Small Blocks" Publication by Graham Hansen. Published by CARTECH. www.cartechbooks.com Good luck with the truck. I was getting 10 mpg with the 350 I took out. Now getting 11.5 mpg with the vortec head 400. I would give credit to the heads,being a much newer and better head than the older design heads.
 

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Discussion Starter #10
thank you Guys
 

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Discussion Starter #11
gears will change after the 6 is gone - Probably 3:73 or just a wee higher - for fuel miliage
 

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Is your truck a 2 or 4 wheel drive ?..........Eric:)hand
 

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IF you stick with EFI, try to use your TPI manifold. They are bottom-end torque/hp intakes. They run out of breath around 4500, which is why people started making larger-tube runners for them. However, for towing, TPI is an excellent intake.

HOWEVER, if you changed to Vortec heads - which is an excellent value and will definitely put your motor where you want it powerwise - you would have to spend a few more $ and get the Vortec TPI base. The runners and plenum will bolt right to it. Ultimately, that would be the best of all worlds for you.

I would keep the cam down around 218/222 @ .050 and .450-.480 on the lift. That would still be a flat-tappet motor / unless you want to spend the coin for a roller setup, but not necessary. The smallest Lunati VooDoo (256) would be an excellent cam choice for your application. I have just finished breaking-in the 262 version and it would probably work for you as well. It works well off-idle, but really starts pulling at 1400 or so. The 256 version would probably allow you to de-clutch at idle with your boat in tow. The VooDoo 256 cam with a TPI intake would provide more bottom-end than you could handle.
 

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how to you plan on firing the injectors or ignition without the optispark distributor behind the water pump? tpi's in the 92's camero's had optispark telling the ecm when to fire the injectors and when to toggle the ignition coil.
 

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how to you plan on firing the injectors or ignition without the optispark distributor behind the water pump? tpi's in the 92's camero's had optispark telling the ecm when to fire the injectors and when to toggle the ignition coil.
Thought those where th 93' up
 

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best bet if you want a reliable engine with some torque for towing and having some fun here and there. junk the tbi . stick with a 600cfm to 650cfm carb .
biggest mistake alot of people make is puting to big of a cam in. stick with the basics and dont over do it your not building a race car . deffinatly need some 3.73 gears in the rear end.

just my own 2 cents i been building and toyin around with motors since 9th grade

ive done my fair share of puting in too big of a cam and going big with the carb .
 

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two wheel . freway cruiser -
Why so big of tire's on a 2wd ? do you like the 4wd look ? I had a 67 chevy 2wd lowered 2/4, short bed, 350 cid -500cfm carb- turbo 400- 3.07 posi - ,245-60-15 tire's, Ran 2400 rpm at 60 mph , got 12mpg LOADED with camping gear - 55 gallon drum of alky-and pulling my hydro , went with the small carb for low end throttle responce, IT RAN GREAT, With the truck empty I got 17 mpg , NOT BAD FOR NO ELECTRONIC'S , WISH I WOULD HAVE NEVER SOLD THAT TRUCK..................Eric:)hand
 

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Thought those where th 93' up
True, '92 still had distributor. I had a '92 TPI motor in a '57 sedan delivery. Still batch-fired injectors. And, he could get a Holley Commander 950 setup for TPI. They even have a proprietary harness.

EDIT: Here is the info for Holley's stand-alone TPI management. Now, after having two vehicles that I converted from carb to EFI - both Commander 950 based - I can't agree with the "most powerful and capable ECU". Not a BAD unit at all, but others have much more capability for advanced operations.
This Holley Commander 950 kit is intended to replace and upgrade the existing fuel Injection electronics of 1985–1992 GM TPI engine applications. The Holley Commander 950 is the most powerful and capable ECU available on the market today. Capable of driving up to 8 high impedance and 4 low impedance injectors, the Commander 950 can provide all the power and sophistication required for any street or strip fuel injected motor.
Commander 950 Engine Management System Kit 1985–1992 GM TPI Engine applications.


Installation Notes
These systems are designed only for fuel and spark management. Items such as cruise control, transmission control, AC, ABS, etc are not controlled by the Commander 950.





Features
  • <LI class=feature>Commander 950 ECU
  • Wiring Harness
  • Includes Sensors


Originally Posted by Keepin Haters Busy
best bet if you want a reliable engine with some torque for towing and having some fun here and there. junk the tbi . stick with a 600cfm to 650cfm carb .
biggest mistake alot of people make is puting to big of a cam in. stick with the basics and dont over do it your not building a race car . deffinatly need some 3.73 gears in the rear end.
Don't do the carb unless you HAVE to. The benefits to keeping it injected would take up a whole page.

Yes on the cam. I just made the mistake of putting too big of a cam in a 327. Ended up pulling it apart to put in the small VooDoo.
 

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Don't do the carb unless you HAVE to. The benefits to keeping it injected would take up a whole page.
TRUE


I do agree here,, I was simplying stating what I had and how it worked ,,,
the tpi should be a good thing..........E:)hand

PS: I still wish I wouldn't have sold the truck,,,,,lol,,.......................
 
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