Chevy questions

[Scooter402]

I think Im leaning back toward the T.B.I.

Where's your sense of adventure?

I re read a few posts now. Are we saying that the 90 / 91 Corvette is the one I want? If so Id try and work something out to grab the one I posted earlier.

I belive this is correct.

But honestly, if it makes it any easier... ANY 5.7 TPI engine could be swapped in. You could make life MUCH easier by doing what I did and get an ECM and standalone harness for a MAP system. If you look at the picture I had posted of the TPI in my CJ, you'll see it's got a clean harness with all the ends tagged as to where I go. eBay was my friend there.

 

[Scooter402]

Here's a good article:

Electronic Fuel Injection Mass Flow vs. Speed Density- Car Craft Magazine

 

[tarry99]

I re read a few posts now. Are we saying that the 90 / 91 Corvette is the one I want? If so Id try and work something out to grab the one I posted earlier.

Yes............you should be fine with a 91 ( speed density ) motor. If I was you I would go down to wherever the motor is and hear it run first. Get the complete engine harness and what goes back to the firewall.....on the passenger side that wire loom extends through the firewall and that plug is below the glove box inside.....Also get the ECM it's mounted next to the master cylinder just below the windshield on the drivers side. That loom on that side unplugs at the firewall just below the ECM...... Now there is a good chance that you may opt to use a more friendly ECM other than the GM factory version and will also need an alternate harness........but get as much as you can that goes back to the firewall plugs just in case you need some of that.........
And just to verify what your getting look at the intake track.........that large plastic intake manifold that comes from the grill and enters the front of the TPI system......there should be no wires or sensors inside there.............Only the MAF systems will have a large sensor in that track............again the obvious reason for not using the MAF system is you have no room in front of the Jeep for a MAF intake track system sensor. If you read the article the Speed Density system is great unless your going to hop up the motor.........then the ECM would have to be reprogrammed ...........but with 250 HP and 350 ft lbs of torque in that light little Jeep hopping up the motor will probably be the last thing on your mind. And the first? Tighten up your seat belt! PS you might even think about using that 700r4 Transmission if you have the room. Great Automatic with OD in 4th gear for off road.........Terry

 

[harleydragon]

some of you guys sound like you really know your stuff on fuel injection. But, at the same time it sounds like a lot of headaches and potential problems to me.I'll stick with carbs.

 

[Scooter402]

some of you guys sound like you really know your stuff on fuel injection. But, at the same time it sounds like a lot of headaches and potential problems to me.I'll stick with carbs.

Nah, not really. I'll go back to EFI again as soon as I decide the correct route for me to go. When I put TPI in my CJ, the only problem I had was running pretty rich after startup, which turned out to be my fault anyway. Everything ran beautifully, and started up on the very first crank. The reason it ran rich is because I had the fuel tank down to drop in an in-tank pump out of a mustang (hint, hint, for those considering the swap ) and I kinked the return line when I put the tank back up.

Now for my full story, and why I sold my TPI unit to replace it with a carb, was just as you are doing -- I had gotten into mud racing. While the TPI systems are GREAT at providing torque because of the long runners, they don't have a lot of high-rpm potential without many many mods. IIRC, they run out of breath at about 5500 rpms, which would probably be fine for most guys around here. I was trying to spin my motor up to 7000+, so I knew that wasn't going to do.

But now I live in eastern PA, and there's next to no real racing anywhere near me. I've lived here since 2008, and have barely touched my CJ since then. Over the past year or so, I've gotten tired of it being a yard ornament, so I'm turning it back into something I can use. Every day, hopefully.

 

[HackFabrication]

some of you guys sound like you really know your stuff on fuel injection. But, at the same time it sounds like a lot of headaches and potential problems to me.I'll stick with carbs.

Simple to do and simple to understand:


Yes, there are some wiring challenges:




And you need to install an electric fuel pump:


Other than that, I'm no genius (just ask my wife), and I got it running.

 

[tarry99]

some of you guys sound like you really know your stuff on fuel injection. But, at the same time it sounds like a lot of headaches and potential problems to me.I'll stick with carbs.

Harley..........this is a learning forum.
I'm still old school ...........but I'm tired of the old stopped in the middle of an off camber hill with a flooded carburetor that will not keep the motor running........

Then see these guys with Fuel Injection go up the same hill stop for a minute , have a sandwich and then keep going.......

 

[ThisGuyUKnow]

Pete, I don't know how adept at wiring you are but if you go with a 90-91 TPI 350 I have all the wiring diagrams already. I can send them to you. The harness and ecm for my AMC 360 TPI project came from a 90 TPI vette. I have a very good handle on the wiring (yes you can poke at me because the project wont run yet) so I would be willing to help you out however you need.

 

[Petescj]

Where's your sense of adventure?



I belive this is correct.

But honestly, if it makes it any easier... ANY 5.7 TPI engine could be swapped in. You could make life MUCH easier by doing what I did and get an ECM and standalone harness for a MAP system. If you look at the picture I had posted of the TPI in my CJ, you'll see it's got a clean harness with all the ends tagged as to where I go. eBay was my friend there.

Yup we're gonna have to talk if this is the way I end up going. Whats the Ebay harness run? Im betting the extra cash would be worth it for me.

Whats that from? Thanks for the response. Looks like a whole different animal with that intake configuration. I have much to learn , thats for sure.

 

[Old Dog]

I believe Hack has a ford 302.
He'll correct me if I'm wrong.

 

[Scooter402]

Yep, Old Dog is right -- that's a small block ford with a Cobra intake setup on it. I built one of those for a buddy with a YJ.

I have to report that I had it backwards with the versitility of MAF vs. MAP. MAF is the one that is more versitile, and MAP must have major changes re-programmed into the ECM. Still, MAP is easier to wire, and can be cheaper without the expensive MAF sensor.

I've got diagrams for all years of TPI wiring with my TPI manual. I got carried away reading them today. I saw that this book is actually copywrited, so I guess I can't just scan and post the info...but I may be willing to share it through other avenues of communication.

 

[ThisGuyUKnow]

Yep, Old Dog is right -- that's a small block ford with a Cobra intake setup on it. I built one of those for a buddy with a YJ.

I have to report that I had it backwards with the versitility of MAF vs. MAP. MAF is the one that is more versitile, and MAP must have major changes re-programmed into the ECM. Still, MAP is easier to wire, and can be cheaper without the expensive MAF sensor.

I've got diagrams for all years of TPI wiring with my TPI manual. I got carried away reading them today. I saw that this book is actually copywrited, so I guess I can't just scan and post the info...but I may be willing to share it through other avenues of communication.

Scoot what is your skill level at programing MAP TPI ECMs? I have the wiring and physical stuff installed in my 360. Im using the waterproof (727?) ECM from a 91 vette. I have the moates autoprom setup with, i think, 2 blank chips. I had the thing running poorly but it crapped out on me after I got the exhaust installed. Once I figure out what the exhaust shop did to cause it to stop running I need to tune the programming to run right on my AMC. I assume this will require me to alter the spark tables and the closed loop peramaters but I know zero about programming. Physical wiring I'm a whiz at but this advanced stuff has me scratching my head.

 

[Scooter402]

Did you happen to have the VATS (vehicle anti-theft system) disabled when you installed the ECM? If it wasn't, the ECM is looking for that little chip on the ignition key that lets the car know it's not being stolen. You can swap the existing PROM out for one that does not have VATS. The problem is if you have done any programming to yours, you'll have to repeat all that to a new PROM.

As far as altering spark tables, I can all but about guarantee that the existing spark tables for the TPI 5.7 should be at least a great start for your 360. If the ECM sensed anything was wrong when it attempts to go closed loop, it will go to a "limp home" mode where it runs safe fuel and timing tables in open loop until the problem gets fixed. At any rate, it should still run. I'm putting my dollar on VATS.

On a side note, do you know if you are getting fuel pressure and spark? What type of distributor are you running?

 

[ThisGuyUKnow]

Did you happen to have the VATS (vehicle anti-theft system) disabled when you installed the ECM? If it wasn't, the ECM is looking for that little chip on the ignition key that lets the car know it's not being stolen. You can swap the existing PROM out for one that does not have VATS. The problem is if you have done any programming to yours, you'll have to repeat all that to a new PROM.

As far as altering spark tables, I can all but about guarantee that the existing spark tables for the TPI 5.7 should be at least a great start for your 360. If the ECM sensed anything was wrong when it attempts to go closed loop, it will go to a "limp home" mode where it runs safe fuel and timing tables in open loop until the problem gets fixed. At any rate, it should still run. I'm putting my dollar on VATS.

On a side note, do you know if you are getting fuel pressure and spark? What type of distributor are you running?

Unfortunately that is a losing bet on the VATS. I will be leaving the VATS in the programming and here is why. On ebay you can purchase a module that sends out the proper signal to the ECM to emulate the signal needed to disable the lockout on the injectors. I am using that module and what I did was wired the ac power to it through an on off toggle switch in the glove box, that way I have an added security feature if I park it somewhere a tad questionable.

I am getting spark, and I am not sure on the fuel pressure I have a gauge enroute in the mail and I will install it between the two fuel rails. The Dist is a GM HEI type that I removed all the mechanical and vacuum advanced stuff, locked out and modified to work with the TPI Ign Module.

The project WAS running. I was able to start it up idle and drive it around the yard but I had no down pipe just headers. I towed it to the shop, unhooked it, started it no issues and backed it into a spot no issues. 3 days later he called me and said it would not start. He did the work, said he got it started but it ran like b-hole. I started it to position it for towing and it was idling like it was missing on a cylinder or something and felt like you were trying to drive in 5th gear. I got it home and tried to start it to move into position where i needed it and it idled poorly for about 20 seconds, then died and as of yet has not started back up. The cold weather came in after that so I have not been able to trouble shoot. But I checked for spark, I poured a little fuel in the TB to ensure it had gas, and I reset the static timing. I'm puzzled but i am sure it is something simple. Maybe the shop knocked something loose.

 

[Scooter402]

Whoops…I guess it's a good thing I've never been to Vegas, huh?

If it were me, I'd start there, though. I'd look at your VATS defeater, and make sure it's wired correctly, all grounds are good, etc. etc. etc. The function of the VATS is to kill fuel delivery (kinda sounds like your problem, doesn't it?). On the other hand, a loose power or ground at your fuel pump will do the same thing, obviously. Unfortunately, I think it's time to start digging back into your wiring and checking out connections.

 

[ThisGuyUKnow]

Whoops…I guess it's a good thing I've never been to Vegas, huh?

If it were me, I'd start there, though. I'd look at your VATS defeater, and make sure it's wired correctly, all grounds are good, etc. etc. etc. The function of the VATS is to kill fuel delivery (kinda sounds like your problem, doesn't it?). On the other hand, a loose power or ground at your fuel pump will do the same thing, obviously. Unfortunately, I think it's time to start digging back into your wiring and checking out connections.

I think it is fuel as well. The VATS defeater is working , it was the first thing I checked. It has an LED that blinks to indicate proper function. The wiring to it checks out. I am using a House brand summitracing external pump and I have requested a replacement just in case. It should be here next week. Also once I get the fuel pressure guage I hope to get a better idea on what is going on with the fuel.

My first though was the wiring, I checked all the connections and looked for any burned wires and couldn't find any. The jeep was running once I wired everything up and since I have not fiddled with the wiring between now and then I am inclined to think that is is something else were and more physical. Once I get the gauge I and put on a new pump I will be able to rule out the fuel pressure regulator. May be clogged injectors. I have had the intake setup for several years in my storage.

 

[C dubya]

You boys damn near have me convinced to stuff a vortex 350 in my cj. let's keep the V8 talk going!

 

[Scooter402]

I'd say go for it! The Vortec is definitely a good strong engine. I'm thinking when I finish everything else I have to do to my CJ, I'll either get some kind of Vortec injection to put on my current engine…or if I'm feeling froggy, I'll build my own.

 

[Peanut Butter]

How about the new all in one EFI throatal bodies, that are self contsined and self learning? Would allow you to use any engine. Any opinions on these? Rod

 

[Scooter402]

I'd definitely try it….IF they weren't $2-3K for them. I can build my own EFI system for a 10th of that. Not knocking them, just too rich for my blood. I'm sure they do work awesome, though. I've only read good things about them.