TBI to TPI conversion Sourcing parts

[ZoomZoom300hp]

Hi Guys
I am the New Guy to this site and it provides a lot of good information

Parts search Throttle cable & Trans shift detent cable
Background :
I had previously converted my Pristine 87 ElCamino SB 305 to TBI 3 years ago and it works flawless.
However I now have the bug (bored) and decided to go to TPI and picked up a very complete unit secured it very cheap.

I have everything (almost) I need to jump in and do it as soon as the snow stops falling and our temp goes above 32 degrees ha

I have cleaned it up & resealed -new injectors and painted everything and rung out my harness and feel very comfortable with this upgrade. I just hate pulling my fender again to route the ECM harness .

What I am searching for is the correct throttle cable/Trans detent shift cable. I have the bracket but the cables apparently on a Camaro were a lot longer then my original throttle and Trans shift cable so I am looking for both Help !!!

Since the TPI throttle body linkage hook up point is a lot further forward then the present position of where a 4 brl Quad/ or my TBI hook up now

Any suggestions:


I had used a painless harness and a Hyper chip for the TBI (it really turned out great and runs sweet .

I read that he Camaros (350) used a higher pressure injector @ 44lb and the 305 takes a lower pressure injector around 19lb
Any truth to this. My 305 is stock. so not looking to dump wasted fuel its not a performance issue

[Fast355]

Hi Guys
I am the New Guy to this site and it provides a lot of good information

Parts search Throttle cable & Trans shift detent cable
Background :
I had previously converted my Pristine 87 ElCamino SB 305 to TBI 3 years ago and it works flawless.
However I now have the bug (bored) and decided to go to TPI and picked up a very complete unit secured it very cheap.

I have everything (almost) I need to jump in and do it as soon as the snow stops falling and our temp goes above 32 degrees ha

I have cleaned it up & resealed -new injectors and painted everything and rung out my harness and feel very comfortable with this upgrade. I just hate pulling my fender again to route the ECM harness .

What I am searching for is the correct throttle cable/Trans detent shift cable. I have the bracket but the cables apparently on a Camaro were a lot longer then my original throttle and Trans shift cable so I am looking for both Help !!!

Since the TPI throttle body linkage hook up point is a lot further forward then the present position of where a 4 brl Quad/ or my TBI hook up now

Any suggestions:


I had used a painless harness and a Hyper chip for the TBI (it really turned out great and runs sweet .

I read that he Camaros (350) used a higher pressure injector @ 44lb and the 305 takes a lower pressure injector around 19lb
Any truth to this. My 305 is stock. so not looking to dump wasted fuel its not a performance issue

Same fuel pressure, different injector flow rating. The 305s used 19# injectors and the 350s used 22# injectors.

[ZoomZoom300hp]

Thanks for the clarification

[Fast355]

Thanks for the clarification

As for your detent cable it would help to know which transmission you are using. I am guessing you could use a throttle cable for a F-car in your G-body Elcamino. On my 1983 G20 van when I TPI swapped it I used the stock van throttle cable. You will also already have an optical speed sensor buffer that can be used to send a signal to the appropriate ECM pin.

[ZoomZoom300hp]

Trans is the stock 200R I had thought is was a 700R4 but I was incorrect
I did secure a throttle and think I found the cable for the trans.

[fastacton]

The last TPI swap I did used Lokar cables and brackets. I was very happy with them (but I hated working on that intake setup, so I'm back to TBI).

[ZoomZoom300hp]

Now you raised my curiosity I like my TBI but wanted to upgrade to TPI

what did you have leaking fuel rails or other problems the system seems pretty straight forward but I don't want a nightmare.
I am installing new injectors and reseal everything. So I am hoping it should be a simple bolt on and set up issue

However one issue that plagued me was the smell of fuel all the time (raw fuel smell) Noting: I ran the 3/8 return lines to the tank and to the bottom of the tank so it did not aerate the fuel in the tank
My buddies say unless you go to a fuel tank designed for EFI this is a problem. why what's the different i.e. my tank 87 El Camino original carburetor tank
I don't understand this since I used an external electric fuel pump drilled & tapped the fuel sender to accept a return line and kept the original vent(return line from the canister .

I have to figure this out. if you by chance had this experience , my passion is I like to do things correctly so if its not right I redo it !

[Fast355]

Now you raised my curiosity I like my TBI but wanted to upgrade to TPI

what did you have leaking fuel rails or other problems the system seems pretty straight forward but I don't want a nightmare.
I am installing new injectors and reseal everything. So I am hoping it should be a simple bolt on and set up issue

However one issue that plagued me was the smell of fuel all the time (raw fuel smell) Noting: I ran the 3/8 return lines to the tank and to the bottom of the tank so it did not aerate the fuel in the tank
My buddies say unless you go to a fuel tank designed for EFI this is a problem. why what's the different i.e. my tank 87 El Camino original carburetor tank
I don't understand this since I used an external electric fuel pump drilled & tapped the fuel sender to accept a return line and kept the original vent(return line from the canister .

I have to figure this out. if you by chance had this experience , my passion is I like to do things correctly so if its not right I redo it !

Raw Fuel smell means the vapors are getting out somewhere.

To my knowledge your 87 El Camino has the same tank as the 85+ 4.3 TBI trucks but a different sending unit. I would use a stock tank that is not tapped into and a sending unit from a 4.3 TBI El Camino. You can then mount a 1992 Astro Van CPI 4.3 pump on the TBI sending unit. On the G20 I bought a fuel rail that had been converted to rear feed and return and hooked it up via braided stainless lines to a set of factory 1992 G20 frame mounted steel fuel lines. The only issue I ran across running the setup was the little piece of fuel line between the pump and the sending unit that came with the aftermarket pump. It was not rated for ethanol immersion, swelled and eventually ruptured allowing the fuel pressure to drop. I was able to limp it home, albeit no power at all, but had to drop a tank that had 15 gallons of gas in it to replace it.

[fastacton]

I didn't have any problems with leaking. I've used plenty of non-EFI tanks without any problems like that. If you're smelling fuel, you probably do have a fluid or vapor leak somewhere. I had to replace injectors a few times and that's not something you can do without removing part of the intake on these and I got really tired of doing that. I know I might be missing out on a little performance by going back to TBI, but the 454 throttle body helps make up some of the difference. Besides, I needed a TBI test mule that I can use as a daily driver as well.

[TINBENDER59]

here ya go

http://forum.gmtruckcentral.com/showthread.php/1125-Convert-a-1988-TBI-to-TPI