305 carb to 5.7 tbi need help

[kfactor239]

Ok the truck 87 4wd 4speed manual (k10/v10 im still confused its a halfton 4x4) started out its happy life with a tbi 4.3. Then one guy decided to put a 454 in it then that blew up so then they put this 305 from an 85 in with a quadrajet. I just got a killer deal on a 5.7 tbi and I want to put it in. The original ecm is still under the dash but the harness is whacked off at the firewall. I went to the junkyard today and got a good harness. I have read that I will need a 5.7 eprom but I have a 4speed with granny in this truck all the trucks in the junkyard are automatics. Will an auto eprom work? I hear that the flywheel on my 305 wont work on my 5.7 but will the clutch? Will the starter? Another issue is the exhaust manifolds on the 305 dont have any egr or o2 sensor. I was thinking of just welding an o2 sensor to my downpipe but will it run without egr? Looking at the truck that I stole the harness from today those egr exhaust manifolds look like a pain. I want to put headers on it eventually how does egr work with headers. This is my only transportation right now the old 305 is smoking pretty bad and I want all my ducks in a row when I do this engine swap. I cant be waiting on stuff. Please help!!

 

[Jims86]

Ok the truck 87 4wd 4speed manual (k10/v10 im still confused its a halfton 4x4) started out its happy life with a tbi 4.3. Then one guy decided to put a 454 in it then that blew up so then they put this 305 from an 85 in with a quadrajet. I just got a killer deal on a 5.7 tbi and I want to put it in. The original ecm is still under the dash but the harness is whacked off at the firewall. I went to the junkyard today and got a good harness. I have read that I will need a 5.7 eprom but I have a 4speed with granny in this truck all the trucks in the junkyard are automatics. Will an auto eprom work? I hear that the flywheel on my 305 wont work on my 5.7 but will the clutch? Will the starter? Another issue is the exhaust manifolds on the 305 dont have any egr or o2 sensor. I was thinking of just welding an o2 sensor to my downpipe but will it run without egr? Looking at the truck that I stole the harness from today those egr exhaust manifolds look like a pain. I want to put headers on it eventually how does egr work with headers. This is my only transportation right now the old 305 is smoking pretty bad and I want all my ducks in a row when I do this engine swap. I cant be waiting on stuff. Please help!!

Ok.
EGR is totally confined to the intake manifold. the exhaust manifolds you were looking at probably had air tubes.
The PROM and Calpack(skinny chip) to 5.7. Auto can be used, manual calibrations can be programmed into any chip by a programmer for a few bucks.
Th issue with the flywheel cant be avoided, to make a long story short, you will need an 87 or newer flywheel.
Not sure on the starter.
since the truck is 87 anyways, the new harness should be plug and play, there is one plug behind the glove box, hopefully they didnt cut it. then the large firewall plug under the brake booster should mate up with the new harness as well. If you are looking to find a home for your carb, We have a guy looking for one in WV.

 

[kfactor239]

Cool thanks. What about the clutch will it bolt up to the later model flywheel? My old exhaust manifolds dont have an o2 sensor. I was looking at my chiltons and only the left exhaust manifold has the o2 sensor so maybe I only need one. Im assuming that my non tbi 305 exhaust manifolds will bolt up. Where whould I find someone to reprogram my eprom?

 

[Jims86]

Cool thanks. What about the clutch will it bolt up to the later model flywheel? My old exhaust manifolds dont have an o2 sensor. I was looking at my chiltons and only the left exhaust manifold has the o2 sensor so maybe I only need one. Im assuming that my non tbi 305 exhaust manifolds will bolt up. Where whould I find someone to reprogram my eprom?

There are a few programmers around that you can send your chip to, i will get you their info later today. The exhaust manifolds will bolt up. Only 1 o2 sensor, and it goes in the drivers side, you can have an o2 bung welded into the down pipe, but as close as possible to the manifold.
Clutch should bolt up. The issue betwix 85 and 86+ is that the rear main seal is 2 piece(86+) opposed to the 85 1 piece. Balancing is different between them too, on interally balanced, the other externally.

 

[Swims350]

yep 85 and older use a 2 piece rms and 86 and up use 1 piece, so honestly you shoul dbe ok going down and getting an 86 or 87 flywheel for stick shift and have it work just fine or even the year to match the motor, not sure if there woul dbe a difference because it would depend on what trans you have and what trans was availible in the later tbi trucks.

would the vss effect anything on his truck using a stick shift and tbi setup jim?

 

[jux]

The two above posts have contradicting info, which years had 1 piece and which had 2?

 

[Swims350]

86 and newer had 1 piece, 85 and older is 2 piece.

I think Jim just made a typo because he knows his stuff.

 

[Jims86]

yep 85 and older use a 2 piece rms and 86 and up use 1 piece, so honestly you shoul dbe ok going down and getting an 86 or 87 flywheel for stick shift and have it work just fine or even the year to match the motor, not sure if there woul dbe a difference because it would depend on what trans you have and what trans was availible in the later tbi trucks.

would the vss effect anything on his truck using a stick shift and tbi setup jim?

Nahhh, the. vSS is mostley to keep the engine from stalling at a stop, or sudden throttle closing, and helps with idle.

 

[Jims86]

86 and newer had 1 piece, 85 and older is 2 piece.

I think Jim just made a typo because he knows his stuff.

Yup, its a typo....I switched years.

 

[Swims350]

I figured so. good to know about the vss it had concerned me after thinking back on it and remembering about my 88 350 tbi.

 

[Jims86]

I figured so. good to know about the vss it had concerned me after thinking back on it and remembering about my 88 350 tbi.

Forgot to mention, it also helps with EGR and AIR controls.
For the most part though, it kinda takes place of the old school throttle kickers that would keep the throttle from slamming shut when there was a sudden increase in vacuum.

 

[IROCmenace]

If you want to use your existing exhaust and avoid an exhaust shop you can install one of these as close to the manifold as possible.

http://www.summitracing.com/parts/avm-30-2355-250

You basically just drill a hole big enough for the sensor. Put this on, line up the holes, and clamp it down.

The quotes I got around here for adding an O2 bung were around $40 with me supplying the $8 bung.

TPIparts.net should be able to program out the Auto trans. They have a chip reprogramming, adapter service. I used them on my Camaro and it works great.