Opinions on TPI Setup

[adis]

Start off, I know nothing about Chevy engines specifically and next to nothing about engines generally.So, I apologize if this is a silly question. The 350 in my ‘80 1 ton is a generic Chevy LT9 (if I decoded correctly: V0331TJW) with equally generic 462625 heads. It’s got some sort of Edelbrock 4 barrel carb on a steel intake. It runs fine and I’m content with the power level. My truck is used for home projects, hauling dirt or sod or garbage to the dump, etc. It gets about 10 mpg and is difficult to start even in warm weather (manual choke), although once warm it is fine. I do take it on the highway but I do not believe that I run it much over 5000 rpm (no tach). I have not (yet) pulled any stumps with it...

I’ve read about the L98 TPI and in the context of most of the discussions I’ve read (usually with respect to gaining HP) everyone usually comments that, given the torque production across low and mid rpm range, the L98 would be “a great truck engine.” It seemed to me that if this were true, I could benefit from more reliable starts (particularly in cold weather), perhaps a bit of a bump in fuel economy, and maybe even an increase in torque production that fits within the typical operating range of my current engine.

So, my question is, is it feasible to install a TPI (intake, injection, computer, basically all of it) on to my generic SBC as is, and get it running for an amount that wouldn’t cost more than simply buying some relatively cheap later generation engine. Say I got the TPI for $500 and everything worked. If I worked out the fuel, and got it tuned right would it, in fact, be a good truck engine, and would the mod result in the improvements I would be seeking?

Sorry for the ramble, and thanks for any opinions.

[Warrens69GMC]

The TPI is a great truck motor, but I would hesitate to use it on your current engine. Your best bet is to get a Corvette/Camaro/Firebird complete car for the transplant - it would include the 700R4 overdrive transmission. This would prevent you from mixing parts and possible giving up on the swap.

You could also go with a 5.3ls swap and the 4L60e.

Both should cost around the same to swap over, around 5k of you only do the basics and you do most of the work yourself.

[adis]

Thanks for the reply. I was thinking of the swap as more a cheap alternative to an aftermarket TBI or similar system. As I said I’m happy with the 350-400-205 setup I’ve got, I just thought the TPI might be a way to address some of the issues mentioned above. Short of finding a vey good deal on a complete running L98, if I was going to sink $5K into this vehicle, I would do Just what you suggest with a Vortec swap. But this truck is not worth it for how I use it. I guess the TPI isn’t something that you can just bolt onto any gen 1-2 SBC and with a proper tune enjoy whatever kind of benefits it might offer over what I’ve got now (a poorly tuned carb) - even with, say a properly matched cam.

[Bigdav160]

I guess the TPI isn’t something that you can just bolt onto any gen 1-2 SBC

I have run a couple different TPI engines in my trucks but I cannot remember all the details. Some years bolt on other years need some slight modifications.

[LS short box]

In the MPLS area there is company called TPIS. They have done a lot work on the TPI systems over the years. Might give them a call for advice.

[Ziegelsteinfaust]

Originally Posted by LS short box

In the MPLS area there is company called TPIS. They have done a lot work on the TPI systems over the years. Might give them a call for advice.

The hot ticket with the TPI if your willing to mix, and match. Is to use the 411 pcm, and a Vortec distributor.

The LS is a better bet by the time your done. Unless you have a love for the tpi

[AcampoDave]

Do you have an Edelbrock carb on the stock cast Iron Quadrajet manifold? Reason I ask is that sometimes I have seen that combo get a vacuum leak at the base of the carb where it seals to the intake. When its idling some WD40 sprayed at the carb base can reveal a vacum leak. If the idle picks up when you spray it...its got a vacuum leak. Maybe you need an adapter for your carb like this.... https://www.ebay.com/p/191985532?iid...CABEgKzWvD_BwE check out what the first review has to say for this item.

[GASoline71]

Seems like a lot of money and work for something that can be "fixed" with probably the correct carb setup and an ignition tune up.

Gary

[toolboxchev]

Those motors did produce good torque numbers down low. Me on the other hand did not like the very few years they produced them.

My novice understanding is that everything for them is very specific. Lots of stuff does not cross over.

Someone gave me one of those motors in the 2 bolt variation. I ended up selling it for a core.

Roller cammed TBI were a bit more common with lots of them still in use. 4 bolt main varieties used throughout the 3/4 ton truck lineup.

I come from the Era of Simplicity, so its kinda hard to change my thinking. Most likely a good tuneup and checking/fixing vac leaks and other issues is going to be WAY cheaper in the long run. You may gain a 1-2 miles a gallon either way driving a brick. Those TPI's are not cheap when you have all the electronic issues/parts sorted out.

My 2 cents.

[Warrens69GMC]

Originally Posted by toolboxchev

Roller cammed TBI were a bit more common with lots of them still in use. 4 bolt main varieties used throughout the 3/4 ton truck lineup.

...My 2 cents.

No roller cammed vin k (TBI) in trucks, 4 bolts in trucks only with flat tappet cams - not all are roller capable.

TBI - 1987-1995, 1996 for vans
Vortec had roller cams - 1996-2002 including vans

[A1971Blazer]

I bought a wrecked but running and driving..... '92 Trans Am with the 5.0 TPI
I put the engine in a Jeep that was purpose built for off-roading/rock crawling
It had great power off idle and lots of torque...which was perfect for my application
Reliability was excellent....and it just looks cool with the intake runners...
There are still several vendors that offer tuning for the TPI....I know where there's a complete 5.7 one for sale for 1K...have thought several times about buying it to put in my '70 K/5...
The Corvette L98 had aluminum heads....the Camaro and TransAm were iron heads

[RichardJ]

The '87 and up L98 Corvette 350 had Alum heads and roller cam ( A small number of '86 did also).
By themselves, the L98 Alum heads are considered junk, but they are part of what gives the L98 its' low end torque.

The L98 Corvette had 2.59:1 rear gears PLUS the .70 overdrive in the 700r4. That's tall.
I have always thought the L98 as a complete package would make a good truck engine, but only as a complete package.

If you found a complete, original '87-'91 alum head, roller cam L98, I'd say go for it.
Most of the Camaro/Firebird TPI engines were the LB9 305 in. version and look identical.