Need some advice...

[bnjny]

I have a 1988 3/4 ton 2wd Burban... 350 TBI that is now carb... The wiring is all there, I have the TBI parts... What I want to do is go to some sort of injection set up without ignition control... I was wondering if it can be done... I just want to run the vacum advance HEI... Can it be done? Or should I just convert to some form of EFI instead? I would like to do this for a minimum amount of money and do it myself...

I am looking for more towing performance and better all around mileage (isn't everyone?). I don't want to get rid of the 350 right no, as it is a later L98 engine that is in good condition with low miles...

I get about 13 mpg empty on the highway... With a light load (about 3k lbs) it is about 7-9 mpg.

I figure between some aero tweaks (a frt spoiler and a way to push the air over the trailer to reduce drag), a Od trans and with EFI I can increase my 15 mpg without a trailer and maybe dip into the double digits with a light load...

Any and all help will be appreciated.

[squirrel]

Re: Need some advice...

If you get a MS and connect it to a TBI it should work fine. I don't know how much you'll gain, I got 13.2 mpg on the trip to Bville in our 87 suburban with the original EFI all in good working order, and no overdrive.

[Matt Cramer]

Re: Need some advice...

We're working on a project car of a similar nature - TBI and a vacuum advance distributor on a 350. The ECU gets its tach signal off the negative terminal of the coil.

[bnjny]

Re: Need some advice...

I just need some info on how to hook up the TBI with the vacum HEI or should I go EFI? I figure with an overdrive and the fuel injection I can get up to 15 mpg...

[TheSilverBuick]

Re: Need some advice...

Hook advance vaccum to ported vacuum on the TBI... It might not even throw a code. I'd have to look up which wire's going to the distributor aren't needed anymore. The TBI should run just fine. If it does throw a code you could probably get a chip burned to ignore the timing.

I'd get an MS2 and this adapter board :

http://www.diyautotune.com/catalog/megasquirtii-tbi-746747-adapter-pcb-p-187.html?osCsid=bbc1173ace3d3915e8c7596f565aa345

To use all the factory wiring and let you have total control over fuel and spark (apparently will even control the lock up on the torque converter if you upgrade to the overdrive). Think you could have a leaned out fuel economy tune for around town and a power tune for towing.

[squirrel]

Re: Need some advice...

I just need some info on how to hook up the TBI with the vacum HEI or should I go EFI?

I don't quite understand the question. Do you want to reinstall the original fuel injection system minus distributor, and not have the timing controlled by the computer?

[bnjny]

Re: Need some advice...

Ok, my fault for not explaining clearly what I want...

I would like to run TBI or some form of EFI, where timing is not controled by the computer... OR if it makes more sense to use a system that controls both... I am looking to add the Gear Vendors overdrive or a 4L80 down the line... After looking over the TBI unit and all the stuff that was pulled off the truck. I think I might be better off starting from scratch with a MS type of system. One that maybe a plug and play, or with minor tuning will work well and trouble free.

Thanks!

[squirrel]

Re: Need some advice...

Ok, that's what I thought in the first place...my first answer still applies.

But it might take you a day to get it working, judging by Randal (TheSilverBuick)'s recent experience.

[dieselgeek]

Re: Need some advice...

Ok, that's what I thought in the first place...my first answer still applies.

But it might take you a day to get it working, judging by Randal (TheSilverBuick)'s recent experience.

Randal's learning curve is faster than average. By a lot. I say give yourself a few weeks no matter WHICH efi system you choose. Being under a deadline always results in disappointment, and rants about how "Brand X EFI is a crappy system"

-scott

[TheSilverBuick]

Re: Need some advice...

I agree 100% with Scott on the time frame thing, set yourself a deadline and you will not only shoot right past it, you will give yourself a lot of stress. I'm taking my sweet time getting it right, rather than short cutting it (like power supply with a toggle switch ;)) and will spend weeks (if not months) fine tuning the EFI on the streets then I'll see how it matches up against Scott's and 30 minutes with it on the dyno, haha. But really you have to have patience.

(I'm currently battling electrical issues inherent to a 41 year old car, but when I got power it fires right up and idles well, it wasn't hard to do in my opinion)

[bnjny]

Re: Need some advice...

Thanks guys... I'm going to look around and start collecting parts as this will be a winter project.