who knows about it

[Mr.Jimmy]

Anybody ever put stock tbi (manifold included) off 350 on a 70's model block? I read somwhere that the center bolt holes need to be machined to fit old style heads. One of you big muther truckers know about doing this. I bought a 88 sub for 150 bucs and grabbed some fenders, front doors, tbi (computer, harness, sensors, manifold,etc.) and then sold it for 100 bucs. I reeeeeeeely wonna put it on the jimmy, but need more info. help.

 

[bronc3buster842001]

yes got to machine the center bolt holes out makes it a little tricky to tighten the bolts when u put it all together

 

[mouse]

Yes the center bolt holes need to be addressed, but they don't need machining. I used a dremel with a cutting bit and slotted the holes to match the old-style heads. Then, I shaped the top of the manifold so the bolt head would sit close to flat. I used a spare small block on an engine stand for test fitment.

I have no oil or vacuum leaks running this set up for over a year now.

 

[Mr.Jimmy]

Im gonna try to do the work myself. Hopefully I dont F*** it up. How about sensors, are you using all of them? If not, which ones arent you using. I have a holley dual plane on it right now, should I keep it and get a adapter plate for the tb, or tweek the stock tb manifold?

 

[diesel4me]

right way--quick way!..

Yes the center bolt holes need to be addressed, but they don't need machining. I used a dremel with a cutting bit and slotted the holes to match the old-style heads. Then, I shaped the top of the manifold so the bolt head would sit close to flat. I used a spare small block on an engine stand for test fitment.

I have no oil or vacuum leaks running this set up for over a year now.

You did it right!..but I've seen guys use old rocker arm balls under the bolts,to avoid having to machine the manifold so the bolts sit flat on it..works slick!...

 

[mouse]

Im gonna try to do the work myself. Hopefully I dont F*** it up. How about sensors, are you using all of them? If not, which ones arent you using. I have a holley dual plane on it right now, should I keep it and get a adapter plate for the tb, or tweek the stock tb manifold?

I'm using all the stock, factory sensors.

I have higher than stock compression, slightly bigger cam, some head work (bigger intake valves) and a .040 overbore to go with my eagle crank. To get it to run right I had to up the fuel pressure to about 17.5 psi, and I'm running a custom chip.

It runs great, and the truck responds much better than when it was carburated. It was definitely worth the effort I put into it.

 

[Mr.Jimmy]

exactly the kind of info i was looking for! Hey mouse, what kind of horses would you say youre pulling over carbed? and how about fumes, big difference or wut. thanks again for all your input guys! u-roc

 

[mouse]

I didn't go all-out for HP, but the machinist (with many years experience) told me that its probably around 260 to 270 HP. But high HP wan't my goal. Adequate gearing can make up for the HP...

The Tq figures escape me, but it starts better than a carb ever did. It also has no problems with mountain altitudes or off camber situations.

I wanted a reliable engine that I could find parts for in the little towns where I wheel (Idaho, Montana, Utah, etc.).

It can handle the 87 octane gas. When I ran it for a test, I didn't record any knock counts while datalogging. Using lower octane gas was also a goal. I usually treat it to premium every other tank.

 

[Grim-Reaper]

Summit and Jegs sell a kit to deal with the center bolts. I for the life of me can't remember what they call it.

You next problem is the ECM is probably not going to be happy with the cam.

What sort of vacuum does the engine pull? if the cam has the vacuum down the MAP reading is going to piss off the ECM.

when you salvage the parts did you pull the cluster and dash harness? The 88 has a VSS in the back of the speedometer. Without it it may give you some idle issues. If I were doing hte swap I would pull all the harness for the inside dash and do the swap just so evertying will be exactly like the 88 it came out of. The rest of the body harnesses will plug in to the 88 dash harness.

If you pull good vacuum and you have the cluster to swap in it may be fine to where you are happy with it.

If it has run issues then you need to down load winaldl and data log that puppy and have a custom chip burned.

 

[Mr.Jimmy]

advise well needed thanks. i did pull the intire harness and all sensors so when the time comes, its all there. what do you guys think of tbi adapter plate vs the stock maifold. i have a holley dual plane under the carb now. input please. say mr. reaper, what gears go well with 38" tires and 700r4

 

[Grim-Reaper]

Have you ever seen what a TBI looks like for a 87-89 454?

Try the adaptor...if it doesn't work then swap the intake.

 

[Mr.Jimmy]

what would you say i could pick one up for at a junk yard? wihch sensors can i scrap and still run? where can i find and exhaust weld-o-let for the o2 sensor?

 

[Grim-Reaper]

what would you say i could pick one up for at a junk yard? wihch sensors can i scrap and still run? where can i find and exhaust weld-o-let for the o2 sensor?

Sensors to scrap....none. They are all needed and you will throw codes without them. the exception will be the VSS but you might have to burn a new chip a lot of times. You can get a drive through VSS and that might be cheaper then a chip.

Go hit the links post in the man 73-91 section. there is a TON of EFI links in there. "3rd Gen" is one of the better ones and Jags that run has the VSS info.

That adaptor was on 454's 87-89. 91 they went with a different intake like the one you have for the 350.

 

[Mr.Jimmy]

thanks grim. i checked summit for that bolt kit. i found part# hly-90748. is this it? do you suggest i install everything in the truck and running it before i buy a chip, or can i get an offroad chip and put in right away? please reply