how much will a stock '76 truck motor take?

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you dont need power brakes. if you drive for a little bit without them you will not even notice they are gone.ditch the brake booster. with 7 psi and no more, you could use the stock short block. it has 8.5:1 comp. the heads flow really well in stock form. only vortex will outflow them stock. get a small cam that is ground for a turbo and you could easily build 450+ hp with motor. keep rpms under 6000 and it should live.
 
Flythebowtie is right. Big cams with lots of overlap bleed off boost, you are much better off getting a Turbo ground cam. I don't think you need vacuum tanks turbo cars still produce alot of vacuum. Im not sure what the boost would do to the booster though.
 
A stock cam will work really well for a turbo application. If you do build the motor at all build it for torque and let the turbo's feed the top end.

As for boost and a master I'm slightly confused myself. My Talon has no valve inline and the brakes work great all the time. But a GN with no valve in it won't have any assist right when you get off boost, you have to wait for the vacuum to build up. Maybe the Talon has a valve in the master, I'm not sure. So just buy a $3 one way valve and you'll be cherry.

A low compression motor with high boost will make more hp than a high compression motor with low boost, aka you get more hp from boost than you do compression. Why do you think mid 80's F1 cars cars made 1800hp on 1.5 liters and 40+psi. But I wouldn't worry about that anyway because your biggest weakness is going to be fuel. You can only do so much with 93 octane.

For a street car I would stick to between 8 and 9 to 1 compression. If you have the option 8.5 is almost a perfect balance. With high compression you get much better off boost response and yes it does spool up the turbo faster, but again I wouldn't worry about that because with the size turbo your probably going to run the motor should spool the sh*t outta them (or it) by 2500 rpm.

The same goes with timing. The car will run much better off boost with more timing.So don't retard the sh*t out of it just to run more boost. You might want to run a little lower but try to keep it as close to stock as possible. My Talon runs 18* at WOT and my GTP is around 15*.

If you have any more questions let me know. I'm huge into pressurized engines and have built/ help build a bunch of turbo cars.
 
A low compression motor with high boost will make more hp than a high compression motor with low boost, aka you get more hp from boost than you do compression. Why do you think mid 80's F1 cars cars made 1800hp on 1.5 liters and 40+psi.

I agree with this but for a streetable low buck build up I don't think it would make much difference what way he went. He will be limited by his internels on a low buck build up.
 
I never said if he should go one way or the other. I was just clearing up the confusion as to which makes more power.

And my suggestion for his build up is to not even touch the motor and just run as much boost as possible for his application. His max safe boost level is going to depend on and not limited to head design, available fuel, injector size, timing, pre turbine exhaust pressure, intercooling. It's all about keeping those combustion temps down baby. 😀

If your going the junkyard route deffinately do a twin turbo set-up. Your not going to find a properly sized stock turbo that will let the engine breath at high rpm which is just going to stack up cylinder temps which equals knock which equals kaboom.

On the twin turbo Fox-body we did we went with early Turbo-coupe turbos. I think they were Garret T25's but the early Turbocoupes got a larger A/R ratio than the later ones as well as the 2.3 Turbo mustang,so they were much better suited for low backpressure, high rpm use.

A great candidate for turbos for you would be MHI 14B's. They came stock on 90-94 turbo DSM's and are good for about 300 crank horse each. Plus they can usually be had for like $100 in mint condition.
 
i'm actually going to do a blowthrough carb setup.

I'm definatally eyeing up those Turbocoupe/SVO mustang turbo's

my fuel system is definatally going to be a challange.
Actually around here, octane really isn't a problem, i could always run E-85 in the car.

i really do appericate all the help you guys are giving me here, its definatally a TON of knowledge.

my motor is alread 8.5-1 compression, so i'll be fine there.
i'm just trying to put a list of small stuff together.
i know i'm going to need an electric fuel pump, a fuel regulator and somthing that adjusts the fuel pressure according to motor boost.

i think the power brakes would work without a problem, cause ususally when you brake your foot is off the gas and the carb is closed not letting air in creating vaccume.

But who knows, i'll find out though.

i'm definatally thinking of pulling the motor i have and starting from scratch.
 
ONE EYE said:
it is stated that the new PM (powdered metal) GM rods that come in the injected trucks are capable of handling up to 500hp. they are gms replacement for the older PINK rods.

this is one alternative to aftermarket rods.

i am a low budget junkyard type of guy. lol :twisted:

what years did these rods come in?
i'm interested to know what other budget parts can be had from a bone yard.
 
If you want basically everything you'll need to know about setting up your blow-through carb set-up go to your local Barnes&Noble and read the chapter on it in Corky Bell's Maximum Boost.

I have said book and it covers every aspect of turbocharging from designing to components to building. If your serious at all about having turbo's be part of your life I think it's a must own.

Here's the link
http://www.amazon.com/Maximum-Boost-Tur ... F8&s=books
And that's a sweet deal, I was a sucker and paid the whole $35 🙁, even though that was like 5 years ago.
 
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