ECC to TPI Upgrade

[IndyJimW]

I'm looking to replace the Electrontic Controlled Carburetor with a Tuned Port Injection system has anyone done this and what was your experience. I believe I'll get better drivabilty, better mileage and more low end performance from my 5.0L. Is there any clearance problems? I'm looking at a system from a '89 Firebird.

Jim Wood

Edited December 18, 2007 by IndyJimW

[Gunslinger]

TPI is an excellent system to use. I think the headaches you'll run into are making sure you get the complete system from the donor car, plus you'll need an electric fuel pump. The ecu from the donor car may have to get a custom tuned chip to match the 305, transmission and rear end ratio specs of your Avanti. It's nothing that can't be done, but it may well take time and a lot of headaches getting things correct.

You might be better off by buying a standalone system like the Edelbrock Pro-Flo or Holley Commander EFI. They come complete with everything needed but are not inexpensive compared to getting used parts from a donor car.

I have the Edelbrock Pro-Flo on my '70 and am completely happy with how it runs. It took a bit of time to get it dialed in, but it does run excellent. There was also a bit of fabrication needed to fit up an air cleaner but there are lots of options to doing that.

[Charlie Kile]

TPI is an excellent system to use. I think the headaches you'll run into are making sure you get the complete system from the donor car, plus you'll need an electric fuel pump. The ecu from the donor car may have to get a custom tuned chip to match the 305, transmission and rear end ratio specs of your Avanti. It's nothing that can't be done, but it may well take time and a lot of headaches getting things correct.

You might be better off by buying a standalone system like the Edelbrock Pro-Flo or Holley Commander EFI. They come complete with everything needed but are not inexpensive compared to getting used parts from a donor car.

I have the Edelbrock Pro-Flo on my '70 and am completely happy with how it runs. It took a bit of time to get it dialed in, but it does run excellent. There was also a bit of fabrication needed to fit up an air cleaner but there are lots of options to doing that.

Personally I'm going to go and change the whole thing. Jasper 350, aluminum heads stainless valves. TPI induction. 3yr 100k warntee incl. labor. with a serpentine belt system.

Lots more power an at the samt time probably better fuel economy depending of course on how it's driven!

Charlie RQB3921

[Gunslinger]

Charlie...

Replacing the whole thing is what I did...GM Performance 350HO crate engine with the EFI installed and a 700R4 behind it. I considered the GM Ramjet EFI but was told by a speed shop owner I trust that GM was having some problems with it in service, plus it's a tall system. I thought there would be definite clearance problem as well. I went with the Edelbrock system since it's a proven system and I've always had high respect for Edelbrock products.

You'll find with the serpentine belt system, unless you plan on installing electric fans, you'll have to modify the fan shroud. It requires a few notches cut. That and you'll need a reverse rotation fan and fan clutch.

I understand when you said "Lots more power an at the same time probably better fuel economy depending of course on how it's driven!" It takes no effort at all to smoke the tires in the first three gears!

[SBCA96]

I would suggest going with a complete LT1, the lower intake plenum will allow dropping

the body to Stude height on Stude framed cars. The engine will make more HP and is

a much more reliable/troublefree setup. TPI is great, mostly, but avoid the MAF driven

units from the mid 80's, opt for the speed density ones from the late 80's early 90's. It

will require the same fuel pressure for either system = 40 psi over the 7 psi of the ECC.

This will require a different fuel tank/pump setup. If you are going through this much

hassle, use an LT1 and get the full benefits. The LS1 would be great, but requires more

work to get it to fit. LT1 is almost bolt in by relocating the A/C pump to the Vette spot.

Tom

[Charlie Kile]

I would suggest going with a complete LT1, the lower intake plenum will allow dropping

the body to Stude height on Stude framed cars. The engine will make more HP and is

a much more reliable/troublefree setup. TPI is great, mostly, but avoid the MAF driven

units from the mid 80's, opt for the speed density ones from the late 80's early 90's. It

will require the same fuel pressure for either system = 40 psi over the 7 psi of the ECC.

This will require a different fuel tank/pump setup. If you are going through this much

hassle, use an LT1 and get the full benefits. The LS1 would be great, but requires more

work to get it to fit. LT1 is almost bolt in by relocating the A/C pump to the Vette spot.

Tom

I will be going with an electric fan set up. I am already using a 700r4. the rear ratios are 2.86 positraction.

I looked at going with GM but the Jasper has a better warentee Aluminum heads etc and at a lower cost.

I don't think the LT1 makes enough more power to be worth the extra cost.

Charlie RQB3921

[Ernie]

I asked a friend of mine, a Chevy nut, your question. He races a Corvette on road courses and also has a very fast Vega with a small block! Here is his reply:

Ernie,

I'm not so sure I would completely agree with that solution. The LT1 is an excellent engine - it's the same as in my Corvette - but it has its quirks. I think installing a Tuned Port Injection system - on the engine he has now - would be a better system to use, if he wanted to piece one together or get a used setup.

The advantage is, first of all, he wouldn't have to buy a complete engine, and second of all, he probably would be able to use his current accessories and brackets. The LT1 uses a different setup. Plus, if the car is just a cruiser, the TPI offers excellent low-rpm torque.

One drawback, however, may be the height of the manifold plenum. I don't know how much hood clearance there is in an Avanti.

I did just find a source for a complete TPI system on Corvette Forum, if he is interested. Log onto:

http://www.firstfuelinjection.com/

Other choices would be the Edelbrock system:

http://store.summitracing.com/partdetail.a...mp;autoview=sku

or a Holley Pro-Jection system, if he's handy:

http://store.summitracing.com/partdetail.a...mp;autoview=sku

Chuck

Edited December 19, 2007 by Ernie

[SBCA96]

REAL 300 hp is easy to get out of an LT1, and with 251,000 miles on my '93 Z28

I can say its damn dependable. We also have a TPI '86 IROC & it throws codes

more often then Britney Spears is in the news. The Bosch system with the MAF

is terrible, and to turn a MAF to Speed Density is a pain. A running LT1 can be

picked up for 500 to 1000 these days since the LS1 became popular. By the time

you get all your TPI parts together you could be close to 500 bucks. Then you've

got a Frankenstein motor, which if you didnt do your homework can be hell. The

LT1 can be plug and play, there is some great info here that applies :

http://www.carcraft.com/howto/81518/index.html

http://www.geocities.com/hardimon01/Conversion.html

http://www.nastyz28.com/forum/index.php

We are currently installing one into a '78 Camaro, total cost of the engine, 4L60E

trans and plenty of other parts in a 67k mile wrecked Firebird was 2300 bucks.

Compare that to a 4000 dollar crate engine, and its a no brainer. PHR did a

383 crate motor in a 76 Camaro and once they got it to pass smog it had 180 hp.

That was around a 200+ hp drop from what it did in the dyno. Keep in mind the

crate engines are rated differently than the LT1's real world rating.

Height wise the TPI is considerably taller, much the same as a carb :

The LT1 is more compact :

Tom

Edited December 20, 2007 by SBCA96

[IndyJimW]

I can get a '89 Firebird w/ 5.0L engine for a donor car for about $750. It has the later speed density TPI and should match up pretty well with my setup. Not worried about wiring it or possible codes, I'm an ASE Master Mechanic with $25,000 of test equipment, I can figure it out. I was wondering about clearance but don't think it should be problem. Have already installed serpentine belt setup and electric fan. The nice thing about the TPI system is with a change of injectors and the chip I can install a GM ZZ4 long block later.

My '87 Avanti uses a Monte Carlo frame so I don't need to drop body, installed 2" drop spindles to get the rack back. I have a LT1 sitting out back of the shop, but I don't want to go to the expence of rebuilting it now when I have a good engine. I want a good cruiser, don't need alot of HP and from what I've heard elsewhere you can't plant it in a Avanti anyway. I'm getting to old to dragrace, my motto now is "If you can do it in less then 14 seconds and not in bed it isn't worth it."

Jim Wood

[Gunslinger]

and from what I've heard elsewhere you can't plant it in a Avanti anyway.

Jim Wood

You have an excellent point. Due to the front end bias getting the rear tires to hook up in an Avanti can be problematic. It takes removing a lot of weight off the front end, adding a lot of weight in the rear (or both) to gain usable traction. That's one reason why my '70 smokes the tires so easily, if not the main reason. With a more power engine with EFI, the gearing of the 700R4, an aluminum driveshaft and composite rear leaf springs, it's no wonder you have to be careful starting off to save the tires from premature wear!

I remember reading in Andy Granatelli's book "They Call Me Mister 500!", that to gain traction at Bonneville they put several hundred pounds of chains in the trunk.

I'm sure it takes guys who ever drag raced Avanti's a lot of effort and practice to get the best from it.

[IndyJimW]

I use my '87 Avanti as a everyday driver and here in Indiana we get our share of bad weather. Almost got into trouble a couple of times with the rearend breaking loose on wet pavement. After all the 5.0L engine is larger than what Studebaker put in them.

Jim Wood

[SBCA96]

Too bad the 5.0 is a total dog though. I guess by the end of the 80's

it had become somewhat better, but a Stude 289 has more guts. The

Monte Avantis are better balanced though, I would figure they would

be fairly easy to launch well. My plan for the '63 is road course work.

I might play on the 1/4 mile, but not seriously. Once I get the TKO in

its gonna be cake to smoke the 245/45 R17s. I just need to hook up

the factory traction bars again ... or the upcoming Cal-Tracs that is in

the works by Dan Giblin (who made the TKO install kit I am using).

Tom

Almost got into trouble a couple of times with the rearend breaking loose on wet pavement. After all the 5.0L engine is larger than what Studebaker put in them.