So I am eventually going to be converting to MPFI but for now I'm gonna see what i can squeeze out of these injectors. According to my math should be between 525-575 tops. So I have an idea of what turbo I'm goin with. If I buy new I'm gonna do this...

S400SX-75 ETT- Hp rating 1050 // AR 1.10// Turbine 83mm// Flange T6 $649

Will be doing 2.5" hot pipes and 60MM WG dumped to atmosphere. 31x12x4 Intercooler with 3" cold pipes. Stock BBC manifolds turned backwards.

But what about a couple of these others. The specs are listed different and I don't really know how to compare them.

Garrett GT4718
Garrett GT4718 For Sale

Turbonetics T76 - has a .96 exhaust so I assume its a 76/75?
Turbonetics T76 For Sale

76 Magnum- Q Trim???
76mm Turbo For Sale

What about twin 57's? Two small?
Garrett 57mm turbos For Sale

 

ive been watching and replying to your build on NATC and was wondering how long it would be before you go turbo since the whipple is for sale...lol

Jamie

 

That was the whole reason for selling the whipple. BTW it sold this morning, hence this thread. I'm gonna get my ducks lined up and start on it as soon as my trans swap is finished (need to bleed lines, and install new starter that's otw).

Soon...

 

i heard that!! time to get to it.......good luck with everything on it.

i have an extra tremec tko 600 that id love to throw in my truck but im still undecided yet. it makes 438/529 at the tires and the turbo 350 and greg slack converter is alot of fun...not sure if id like changing gears all the time or not. time will tell i reckon....

 

Your OBS truck is probably my favorite truck of that line. So ******* sexy, especially with the rake on it.

 

Sweet! Badd *** truck!

I dont know how well your going to make out with the TBI though,

I had a 95 Tahoe sport, TBI 350, and was going to do a centrifigal on it, but everywhere i looked and checked no one reccommended blowing thru the TBI, i had bought a 454 TBI and had the injectors flowmatched, but never did boost it.

I d like to see your results, are you going to be out much money by trying the TBI vs just going to MPFI intake?

 

We did a blow through with a Paxton and pro charge.
Both required us drill the from to the throttle blade shaft. And install another plate under that, that allows boost psi to push into those holes.
Without this. You will have a slight fuel leak around the butterfly shaft to outside the body.
Since fuel is dropping onto of the butterfly's you will need to combat the fuel trying to get out around both sides.

Pull up some old instructions for a Paxton install on TBI if you can find them.

 

Finally some OBS/BBC love! I've got a 1989 K1500 with a Vortec 454 in it that I'm wanting to boost.

 

Thanks man, yours is one of the best lookin trucks of that bodystyle. I don't know if you read that thread but I took a picture of your truck up to the vinyl place and asked for a stripe like yours, lol. Still undecided on that btw.


Thanks man, theres a pretty big difference in the 350 and 454 TBI's. The TBI has WAY bigger injectors and is actually bigger itself. There's a guy who bores them out but I don't think I'm gonna mess with that.

I already have everything to go the TBI route. For me to switch to MPFI down the road it will take
Intake ~$250
Throttle body (Accufab 4150) ~$???
Injectors ~$???
Software update ~$50

I didn't really follow to well what you were saying. Are you takling about drilling into the blade. Like an idle hole?
I will check out some of the old paxton stuff and see what it says.

I know its hard to come by these obs anymore. There's a guy (LS1freak), his truck is sick. LS and a T70 I believe.
Boost it or build it. If you don't build it, you have to have boost to do anything worth doing. The compression is just so low on our trucks that you have to find a way to overcome that. I guess in the end you could boost it, then build it, then boost it some more.

 

No. We had to drill through the base of the body - to the throttle shaft.
The there was a spacer that had the same matching pattern of holes.
Then the bonnet had a line that ran to that spacer. This pushing air through the channels to the throttle shaft.
This kept the fuel from the injectors from coming out around the throttle shaft.