kossuth

I appoligize if this is gonna get kinda lengthy but I have a few questions to ask the TPI gods . Anyways, I own a 2000 S10 pickup with the 4.3 V6 in it and have had reasonable success modifying the truck and have it running 15.2 at 90.8 mph with a sucky 2.3 60' all boltons. I would like to supercharge the V6 or build it up but the fuel system on these trucks is just so poor that by the time you have it making 275 hp you have to push the fuel pressure upwards of 80 PSI just to keep up with it. I don't want to do that, seems risky on the street.

I am gonna swap in a V8 no question. A LS1 motor is outta the question for cost considerations and the fact the frame has to be noticed bigtime if I want it to sit in what we call the stock position. I am now left with the LT1 or SBC option. The LT1 would be cool but then again cost is a consideration not to mention the electronics nightmare I will encounter trying to get the f-body ECM to work with my factory ABS and guages. With the LT1 I have to use LT1 accessories and if I want to retain the AC I have to notch the frame again to clear the Camaro AC pump and the Vette setup is just totally outta the question for the S10, you won't have any fenders left after you make the room for everything. The nice thing about the TPI motor is it is a SBC and the Vortec is still a SBC and the 4.3 Vortec and 5.7 use the same accessories so I can reuse everything from the 4.3 in terms of rotating assembly on the TPI motor. The last but most unknown avenue of approach to this is the TPI motor. I know the LT1 intake and such is alot better than the stock TPI intake but there are also numerous upgrades out there for these motors not to mention parts are cheaper and actually available. If I go with a regular SBC I believe I can reuse my stock 4.3 V6 computer being the fullsize trucks with the 5.7 use the same computer just differently programmed, that can be altered no prob by a performance shop. I just have to use the Vortec V8 timing cover and reluctor ring on the crank for ignition trigger and that is it being the Vortec has a SFI computer I would just have to modify the wiring harness for the TPI injector setup. I have swapped in a T56 into the truck because I kept breaking the stock 5 speed in it so there are no driveline worries. I will have the EGR disabled on the computer to eliminate that headache. The only problems I am worried about is if I use the Vortec computer I have to reuse the stock Vortec V8 distro. Will it clear the TPI intake or am I gonna have a problem with clearance you think?

I plan to get a 4 bolt main block with the one piece rear main, "to use the LT1 flywheel" using a stock crank with a aftermarket 5.7 rod with flat top pistons bored .030 over and a planned redline of 6200-6500 rpm of course balanced and all. I plan to use the E-tec Edelbrock heads on this motor so my compression ratio would be right up around 10.3:1 with flattops. Complete they run about $1100 through Summit. If some of you don't know the E-tec heads are a aluminum spinoff of the Vortec V8 heads from Edelbrock so I have to use a Vortec compatable intake. Being I plan to keep this thing on the street still, "no emission laws" but I will have cats on it, "needed for inspection". I don't plan to go huge on the cam. Probiably a 114 centerline lift and duration I am still unsure of. In the end this will end up costing just as much as rewiring the truck for the LT1 and dropping in the LT1 I am sure but I hope it should be quite a bit stronger, besides the TPI motor is prettier anyways.

The 200 E-tec heads are said to flow 10% more than the fastburn heads on the intake and 17% on the exhaust, intake runners are 200 cc's and 78 cc exhaust. Do you really think for the money and power gains the E-tec heads are worth it? If the aftermarket vortec intake can't keep up with the heads then I would look into other head/intake combo's or is the TPI setup just outta the question. I am looking at getting up around 300 rwhp and keep it on the street. What manufactures make a quality Vortec compatable TPI base, and which ones are quality? I have head that with these intakes the injector bosses cause a ton of restrictions. Is the common with all TPI intakes or just certain Vortec versions or all TPI intakes in general? If I go TPI I am definately going with a set of siamesed runners and the such if I hope for it to breathe up to 6500 rpm. Thanks for your suggestions and help guys.

smokin87iroc

if you are wanting to keep your abs i think you are going to have to just get a vortech v8

do you not have a separate computer for the abs and stuff separate from the engines computer? i thought the ls1's had that and i wasn't sure about the newer vortechs

if you like an lt1 motor then just build up a nice L98 block and do the lt1 conversion from John McMillian. you can probably get a TPI computer with wiring harness for around $300

i don't know if you can use your vortech intake or whatever on a Gen 1 block. i haven't had any dealings with the vortechs.

your best bet is to get a vortech 350 or else change out everything.

if you have the money do an ls1 and pay someone to do the wiring and notching
Andrew

kossuth

Well, money is kinda an issue being I am military and all we don't get paid much but I do alright, besides I have been planning this for awhile so I have about $3500 stashed away for this as well as upgrading the suspension on the truck to handle the added power and weight and I have 1/2 of that stuff sitting in my garage right now, just waiting to order the shocks. Anyways, Basically what I thought about doing in a much simplier way of explaining is wiring up the TPI engine as a Vortec engine if you understand what I mean. A 1st gen SBC is no different than a 1st Gen SBC Vortec motor, just updated head design and a few other added sensors which isn't a big deal. Any more input or advise would be greatly appreciated. Thanks alot guys.

smokin87iroc

well if the blocks are they same you might be able to do it.
how are the injectors fired? that pretty much the major deal. if you can get the injectors to fire/get correct voltage and what not it'll work like you say.
you will have to do some prom tuning and i don't know if there is a program out there for the do-it-yourselfers or not. but if you can find something give it a shot and it may work

Andrew

kossuth

Injectors are fired with a two wire lead one ground and one hot from the ECM just like the TPI I am assuming. I think the Vortec computer is programmed for a low impediance injector being the stock injectors are only 19 lbs I believe, I know that is what they are on the 4.3 and they share alot of parts with the 5.7. I am just wondering if anybody has any idea if the Vortec distro will clear the TPI intake manifold. I guess I am going to have to go junk yard searching and see how much space there is back there. If I do go the TPI route I might not be able to use that beauty cover if it is tight.

Does anybody have any input on the Vortec style heads and if they are worth it or is it better to go with a Trick Flow or Edelbrock traditional style head and just go with a ported TPI intake and go that route. Thanks again guys.

egmonster

SBC + AFR heads + Ported Edelbrock TPI base + SLP Runners + Stock Upper Plenum Ported. That's my advice to ya . AFR heads are the best you can get, period. If you're willing to pay 1100 for those E-tecs and the limitations they bring (not much vortec aftermarket stuff really compared to TPI) you may as well pay an extra couple hundred and get the AFRs. They will flow better . Make nice nice power from 2000-6500+. You can use a painless wirining harnass too, or something out of a 3rd gen. I'd get the 90+ speed density version... much easier to tune yourself. Read that Sticky article on this section and you will learn all you need to know to tune your truck yourself if you don't already know how already...

kossuth

Cool, so the AFR heads are the way to go then. What are the differences from the MAF to Speed Density setup? Being I plan to retain the stock computer in the truck just rewired for the TPI injectors and such it will be a MAF setup. I am asking this because I still have to use a MAP sensor in the intake but all it does is it is a redundant backup for a fired MAF sensor and to get the manifold pressure before an engine is started to give the MAF a baseline to calibrate itself off of. It has little use when the engine is running. Does anybody have any more advice on this. You guys have been great help. Thanks again

Also I meant to ask how much of a gain in the topend and loss in the lowend will I suffer if I have the runners, upper and lower intake all siamesed? Not that it really will matter because if you are running it hard you will never be below 3500 rpm anyways.

egmonster

Well, the speed density setup is less finicky to tune. The stock MAF ecu is a limiting factor too. It can only read so much airflow because it is running off a slower cpu than what we have lately in most cars. There is more info on tuning your TPI setup with a SD harnass too than there is with a MAF setup. I think in the end you will be happier with the SD . You don't lose too much bottom end actually, and your upper RPM power increases significantly. Definately a worthwhile mod

xookered

A maf system can candle just as much as a sd system. I'm running a 560 hp 383 with a stock ported maf. And since the maf actually measures the air instead of looking through tables, it can respond better to changes. For 3500 you can have a whole tpi setup, afr heads, l98 computer, and wiring harness from painless. If you are only looking for 300 rw, your stock suspension and a ported stock tpi will work fine.

New harness and used ecu- 350
Used l98 motor - 500
used tpi - 300
afr heads - 1200
roller cam kit - 500
miscellaneous - 500
total - 3150 give or take

Do the complete swap