I have a 1977 that I was thinking about converting, the engine is in good running condition, totally stock, but for lack of better terms, anemic. It's a 3 legged fat dog.
S L O W compared to the '84 or of course the '07.

So, has anyone done the conversion? I have found a tpi unit with module from a donor here for 500, but think its going to be 2g before it is done, is it worth it or better off to dump 2g into another engine?

I know I need 55 psi fuel pump, wiring harness, MAP, MAF sensors, etc etc etc, and then there is no guarantee it is going to work, could be a waste of money.

Insight?

 

Get on the line to mrvette He has one with this conversion or real close to it..

 

there's really no performance advantage to FI over a well tuned carb. there is a drivability improvement because you can tune the thing 100000 ways from sunday. but then you also are going from a very simple system like fuel, spark, car runs to fuel, spark but no 1.21 jigawatts from some stupid sensor, car no run. for $2000 you can put on some nice 65cc chamber heads to bump up your compression a bit, drop in a retro fit hydraulic roller cam and an ederbrock performer intake manifold and do a fair job of waking up that car. now you won't be out hunting Z06's but you will notice an improvement.

 

MY install was done 15 years ago, for the first time, and followed about 6 months after buying the car....first up was basic mechanicals and a serp drive, a/c conversion to modern compressor, and new radiator with electric fan in the stock shroud....

the car WAS a muncie 336 geared car got 12-14 mpg at best, with the stock Qjet on it...L48 engine rebuilt by P/owner with a mild cam stock exhausts....

I stuck a TPI on there for 750 bux or so, and it jumped to a highway cruise at 70 doing some 4000 rpm getting 24 mpg....
good for maybe 275 hp or so....

since then with a move south, more freeway useage, and higher speeds, 4000 cruise was not dooable for any time....

in went a roller engine 11+ years ago....a cammed up ZZ4 engine with large runnered TPI and getting 22.2222 mpg at 90 mph cruise....and I was being pushed....some gas crisis....4+ bux/gallon and traffic FLYING, go figger....

I now have a 200 4r automatic in there for some 3 years now...
for the overdrive...

i'ts a speed density system, using the stock junkyard computer and wiring harness ends, being an ole ET I can solder a wire with my fingertip......

I highly recommend the swap as it's a direct bolt on and it's even cheeper today to do it than 15 years ago....

last winter, I modded up a LT1 intake manifold and put it on there in place of the TPI, but kept everything else the same....

runs like a bat outta hell....

 

AND lucky to get 12-14 mpg same as me, UNLESS you buy a wide band O2 sensor, and play with it a LOT, then you still have the operational problems.....you MAYBE able to get 18 mpg out of it without o/drive...maybe....

 

thanks for the input guys.

Any idea of realistic costs?

 

if you want mileage and drivability then FI is the only way to go. if you want to wake up the anemic 3 legged slow dog then FI by itself ain't gonna get it done. i have a pretty healthy 355 in my 77 with a holley double pumper. half my problem is i can't keep my foot out of the 4 barrels. no idea what MPG i get. really don't care either. i drive it for performance.

 

TPI mechanicals with used injectors (be prepared to have to clean them or replace 1-2 of them) is about 250 bux....computers are ten bux at a junkyard, wiring ends are off car harnesses in junkyard, get a nice wire selection at your parts house and just splice it in and shrink wrap or tape, tiewrap wires neatly in sub bundles, the route to each sensor, injectors, IAC motor.....

wire it like a '91 F body V8.....follow the diagram religiously....

chips/cal pack is about 150 bux these days....

so total cost about 500+ bux.....roughly....

BUT you have to do your own install....and learn something....

 

looking at the new Jegs catalog right now.

Edelbrock Performer heads $1150 a pair
Comp roller cam $300
Edelbrock Performer intake $130
Intake with carb, cam and lifters(edelbrock package deal) $640
Misc. odds and ends $500 maybe

so for a little over $2k you can add a 4th leg.............

 

You have a unit
First you have to determine whether you want mass air flow or speed density. The C3 is more conducive to speed-density due to space issues. Mass-air flow is easier to make engine changes without PROM changes. If you are technically proficient enough to make a Camaro harness work they can be bought for $100 or less. I have been told that you can also use a 3.1 Corsica or Cavailier harness with a little work, it uses the same 7730 Speed-Density ECM. Aftermarket harnesses range from about $300 for Painless to $500 for Howell to $700 for Street and Performance. Howell makes a great harness, but for a Tuned Port they do not make one that will control the converter lockup on a 200R4/700R4/4L60 transmission. If you are running a manual or non-overdrive-automatic transmission I highly recommend them. I have heard great things about Street and Performance harness, but do not have first hand experience with them. I also have a Fuel Injection Specialties (FIS) harness and it is OK. The ECM can be had used for $10-50. A good external fuel pump will cost at least $100. I use an 88 Ford Truck external pump, $114 from CarQuest, made in Texas by Airtech. If you have a 78-82 you can use your fuel tank with an 82 sending unit and a TPI pump. An aftermarket PROM with VATS and Emissions codes removed will be $100-200 depending on source and complexity. You will have to add an oxygen sensor to your exhaust, $20 for the sensor, $5 for the weld-in bung, and say $25 for an exhaust shop to weld it in if you can’t. Some harnesses use VSS and some do not. An auxiliary VSS sensor is around $75. To install a TPI I say figure at least $800 plus the TPI unit and whatever repairs are necessary to bring it up to useable status. I have TPI/700R4 in my 69 Corvette (Howell harness) and an 83 Pickup (FIS harness) and I love it. Starts good, great torque, good fuel mileage, easy to swap onto stock engines (although both of mine are complete engines out of 90/91 ‘Vettes).

Differences in years
All Corvette TPI intake manifolds work with the older (through 86) iron heads and the factory aluminum heads through 91. F-body TPI intakes use the upright center bolts on 87-92 and thus fit all 87-95 iron heads (non LT1). Either can be swapped to fit the other with some drilling. F-body has the fuel lines come out on the drivers side and has a central port for EGR. Corvette has fuel lines that come out on the passenger side and has an external port for EGR. Corvette fuel rails fit F-body intakes and vise-versa. The runners are all the same through the years, but the LH runner has a hole for a 9th injector in the 85-88 runners. This can be plugged off if you get a nice LH runner and don’t want the 9th injector or decide to run speed-density. The plenums all physically interchange, but 90-92 have an extra vacuum port for the MAP sensor used with the speed-density computers and wiring. 89 is an odd year, it is mass-air flow but without the 9th injector. 89 up throttle bodies can be used on all years, but a 85-88 throttle body requires a ½” hole be drilled in the front of a 89-92 Plenum for idle air. 89-92 Throttle bodies have a bit more desirable cable attachment. The cable attaches around a circular linkage which has a smoother actuation than the straight linkage on the 85-88. The Corvettes have an aluminum plenum extension over the distributor, the F-body extensions are plastic. The Corvettes use an HEI coil-in-cap distributor for 85-91 (Delco 1103680). 85-86 F-body also used a big-cap distributor. 87-92 F-Body used a small cap distributor with an external coil (Delco 1103479). This same distributor is used in the 87-95 5.0/5.7/7.4 TBI injected trucks. The F-body intake gets it's exhaust for EGR from the center passages in the heads like most SB Chevys. A Corvette intake gets it's EGR exhaust from the RH exhaust manifold/header through a flex-tube to an opening near the distributor-no center passages in the intake. If you are required to keep EGR and you have a Corvette intake, I recommend getting the C4 exhaust manifolds. They are like mini-headers, and have a 2 1/2" outlet. I have them on my 69 and like them.

As far as a throttle cable to use, on my Vette, I used a TPI Corvette cable, 1990 I think (about $20 new GM) but you have to cut the end off inside the car and use a hood-release-cable end (Corvette Central 342138 "cable stop") to get it the correct cable length (the housing is OK). You must use a cable from the type car your throttle body came from if you want to have a chance of not cutting it. Again, 85-88 use a straight pull, while 89-92 have a circular attachment for more smooth actuation and so the inner cable is longer. On my 83 truck I used a TPI F-Body cable and it was OK, but I had to coil it up into a loop in the engine compartment because the housing was so long. I also TPI'd a 72 Chevy truck and used a 90 350 TBI truck cable for it. It was 1/2" short outside if anything, but I was pretty pleased with it all told-I didn't have to shorten it. In a Vette it might be about right. In all vehicles I've done you need a die grinder to square the firewall hole off a bit. All vehicles I've done used the late throttle-body.

Why to get it

I would look into a TPI. They start immediately in winter, have great vacuum, and will get great mileage. I can open the headlights and the wiper door at the same time with no hesitation at all-solid wooomp. With 3.70 gears (and a 700R4 overdrive) I get 18mpg city and 22+ highway. With 3.55 or 3.36 it would be even better. You can probably find a used Corvette TPI engine for $1000 and with an $800 harness/computer/fuel pump you would be set. On a 78-82 you can use the stock fuel tank with an 82 sending unit and TPI pump and be in better shape than 68-77 with an external pump. With the Vette TPI you would have aluminum heads that would remove weight. Even with an F-body iron-head TPI 350 it will be less weight than a stock intake. It will bolt up to everything in your car, use stock accessories, use your transmission, and the visual appeal is awesome. Don't be afraid of fuel injection, it really works.

As far as websites see:
www.corvettefaq.com for conversions or more TPI info at www.fuelinjection.com

 

I've been looking at AFI's TPI system. The intake they use flows better than stock. I'm still on the fence as to whether I want a stock computer, stock with a flash chip, or a programmable ecm with wideband O2. They tell me they can go ahead and set up the wiring harness for a future tranny swap to a 200-4r and for future electric fans.

Here's a link:

http://www.affordable-fuel-injection...Fuel+Injection

This should give you an idea as to maximum cost. Let us know what you end up doing.

DC

 

WOW.

That is awesome information, thank you so much guys!

I found a great deal on one, looks like I found another winter project.

If I could sell my rashed 2008 hayabusa I might buy a complete engine- anyone want a Busa with factory warranty? LOL

 

I have a system off an 88 5.7 out of a GTA Trans Am for sale pm me if interested will sell cheap comes with dist ecm harness and complete FI do not want to jack the thread but I just have this and no intention of using it lmk Mike

 

I have had mine since mid 90s and over 75000 miles. Mr Vette about covered it but the one thing I would add is the overall drive ability is second to none. A stock TPI engine feels like a big block up to about 4000 rpm and that is where most of the fun happens.

I used Street and Performance wiring harness with tags on each plug (so easy a cave man can do it) and step by step instructions.

 

I've got a little over $2500 in my swap (I think...I stopped counting after that)

But I used all new parts (harness, Throttle body, distributor, ecm, custom chip, ect). The only thing used was the intake.



If I did it all over again I would have just bought a complete LT1 engine and harness out of a donor car and went that route.

But as far as parts, go to www.tpiparts.net that's where I got 99% of the parts to do the swap. And don't forget these books as well.

http://cgi.ebay.com/ebaymotors/Chevy...mZ360095335568

http://cgi.ebay.com/ebaymotors/Jagua...mZ220291886856

 

Welllllllllll...........how much does it cost, or how much Can it COST, LOL....Its really fairly cheap (to start), then you can get the bug like me, and then your in alot of trouble. I did the conversion in my 69 rs/z28 camaro. Man i love the FI.....Built a 383 stroker, added all the TPI stuff, got to know Street and Performance pretty damn well, lol...After that it ran so beautiful, but i just could leave it alone, next thing i know, im adding trick flow heads, full 3" exhaust, needed more, added supercharger, needed more, ordered all new Edelbrock High Flow runners, New Edelbrock high flow intake, Holley 58mm Throttle Body, Then sent off to Redman Racing, Had everything Port matched, then couldnt leave satin, hell my motor was chrome, on the phone to my buddies and S&P again, ship off to them for more triple plate chrome work, then ordered stand alone Holley 950 Commander Computer, then bigger fuel pump, sumped the tank, and on and on, lol....Just when i thought it was done, Now i just got in my Lingenfelter Super Ram with a Procharger setup to give me more......Stay simple and you can be $800 - $2500 budgeted, or get the bug and spend 20k+

 

Umm.. that setup attracts fingerprints worse than my apple products.

 

look closely, you wont see any prints, becuase theyll get chopped right the hell off, lol.