Carb back to TBI

[slippy3002]

I believe all the wires are still there. But im not sure. I have a place where I can get all the wiring and everything right out of one of these trucks.
Would anybody go through the trouble of converting it back to tbi. I need to get better mpg. Thats tbe only reason that I am wanting to go back.


Anybody know exactly what I would need to go back to tbi. A detailed list would be very helpful and appreciated.
Sent from my 355 pwered Galaxy Tab 3

What else is in the motor? You will most likely need a tune for the computer. Which you will need to get someone who is good at it. I can't see how its getting that bad of fuel mileage with a carb setup. Are you sure everything is setup right?

Sent from Robland

 

[Tavi]

With that intake manifold your not going to get good mpg. Looks like a Victor Jr. Not going to make much low end with it. I'd swap the vortec heads on the existing engine, get a Edelbrock performer(or your preferred brands equivalent.) and tune the carb(or buy 600 cfm). Properly selected parts, as in not over carbing. Will yield better mileage. My Nova got 17 mpg before I blatantly tore it apart to suck tons of fuel and turn it into lots of power. So I know it can be done with a carb.
This is what I would do. Mostly for price. And at least for me, ease of the swap and tuning. Just trying to get my TBI back in order(for emission standards.) Sensors and wiring, has been quite a task. And everything is there, just not hooked and or working. But good luck. Keep us posted on your decision.

 

[southern_z71_92]

What else is in the motor? You will most likely need a tune for the computer. Which you will need to get someone who is good at it. I can't see how its getting that bad of fuel mileage with a carb setup. Are you sure everything is setup right?

Sent from Robland

I know nothing about the internals. I was told that it was a 355. I havent checked that. Its basically the type of built motor you find in a mid 80s back chevy/gmc truck. The motor is from a k5. Again what I was told by the PO. I think it has a cam in it but if not stock its not much.

Sent from my 355 pwered Galaxy Tab 3

 

[southern_z71_92]

With that intake manifold your not going to get good mpg. Looks like a Victor Jr. Not going to make much low end with it. I'd swap the vortec heads on the existing engine, get a Edelbrock performer(or your preferred brands equivalent.) and tune the carb(or buy 600 cfm). Properly selected parts, as in not over carbing. Will yield better mileage. My Nova got 17 mpg before I blatantly tore it apart to suck tons of fuel and turn it into lots of power. So I know it can be done with a carb.
This is what I would do. Mostly for price. And at least for me, ease of the swap and tuning. Just trying to get my TBI back in order(for emission standards.) Sensors and wiring, has been quite a task. And everything is there, just not hooked and or working. But good luck. Keep us posted on your decision.

The intake is the weiand team g hirise. So the 650 cfm is too much. I guess it doesnt help that the throttle linkage consits of a zip tie. Will having a stage 2 shift kit in the 700r4 have an effect on the mpg

Sent from my 355 pwered Galaxy Tab 3

 

[Tavi]

650 isn't really to much. Might be a little more than you need. But it wont kill that much mileage. The stage 2 isn't helping. But its not going to hurt much either. I would say the intake is your biggest killer. The single plain, divorced runner design is meant for high rpms. Starting at 2800, for that particular manifold. And you said it doesn't have much of a cam. What about stall converter? It sounds like the PO tossed a bunch of parts together and called it good. Just a manifold swap and carb cleaning/tuning should bump you up several points.

 

[southern_z71_92]

650 isn't really to much. Might be a little more than you need. But it wont kill that much mileage. The stage 2 isn't helping. But its not going to hurt much either. I would say the intake is your biggest killer. The single plain, divorced runner design is meant for high rpms. Starting at 2800, for that particular manifold. And you said it doesn't have much of a cam. What about stall converter? It sounds like the PO tossed a bunch of parts together and called it good. Just a manifold swap and carb cleaning/tuning should bump you up several points.

I dont know anything about the tranny other than the shift kit snd some beefed up parts. The guy told me he had it built back stock 2 times and it messed up both and the 3rd time the tranny guy built it up a bit and no isses after that. Ill look into a new intake and possibly a different cam. Ill prolly go with the better flowing vortec heads.

Sent from my 355 pwered Galaxy Tab 3

 

[southern_z71_92]

would anybody recommend this

http://www.summitracing.com/parts/cmb-03-0199/overview/year/1992/make/chevrolet/model/k1500

 

[Tavi]

That's what I would do. Just keep an eye on compression. Compression is kind of free power. The more there is the more power, using the same amount of fuel. But if you go to high, it could mean disaster. Unless you want to start using premium. Which I assume you don't since your looking for fuel economy.

As far as cams. Remember the vortec heads Achilles heel. Lift, you can't run to much. There are kits out there that null this problem. But then you start making more power than fuel economy. The other thing to consider is the intake runner on the vortec is amazing. Exhaust, not so much. I'd run more lift and duration on the exhaust side. I would run http://www.summitracing.com/parts/hrs-cl112561-12/overview/make/chevrolet.

 

[Tavi]

would anybody recommend this

http://www.summitracing.com/parts/cmb-03-0199/overview/year/1992/make/chevrolet/model/k1500

You already have the carb. So you could save on that. I personally like Edelbrock. But that's me. Something about a red white and blue made in America tag on it.

But that will save time and head ache. But not money.

 

[southern_z71_92]

what cam would you recommend with the heads i have. they are double hump heads. from the 80s or earlier. reason being is that intakes to fit on vortec heads are quite pricey.

also what intake would you recommend, edelbrock and other cheaper brand.