I did the tuned port on my '85 with a 350 using the 90-92 computer with
MAP. www.painlesswiring.com has a lot of info and a good list of all the
sensors with part numbers. Chevythunder was a big help for me.
Jeff Engel wrote:
>My setup is a little different from what was in my 85 IROC. The 85 was the
>first and somewhat odd year for the TPI. The 85 had it's own computer and
>was a Mass Air Flow setup. 86-88 shared a computer and were Mass Air Flow
>setup. 90-92 shared a computer and were a Manifold Absolute Pressure setup.
>The MAP setups are easier and somewhat cheaper to install. Plus the air
>intake plumbing is much cleaner. The MAF requires a huge MAF sensor in the
>air intake before the throttle body. MAP does away with this. You probably
>already know this stuff but I wanted to clarify just in case.
>I set mine up like a 1990 Camaro with a 305 TPI and 700R4 tranny. It uses
>all the same sensors as my 85 EXCEPT: no MAF (you add a MAP sensor now),
>computers handles spark control so, no ESC sensor, different computer (use
>'730 computer), eliminate the 9th injector at driver side fuel rail and
>intake runners, and eliminate the cold start sensor at the front of the
>intake manifold. Also, "chip" in the computer must be modified. this is
>easy and a lot of people can do this. I had the VATS (vehicle anti theft
>system) disabled (this lets me start the truck) and I had the EGR codes
>disabled (I eliminated all the emissions stuff). My state does not requires
>emissions testing for my year of truck. The computer controls the cooling
>fan. I got the fan from Jeg's and I used the radiator from the 85. It
>works great and looks great to. The radiator is the exact size to fit up
>front and no I have no radiator sticking up above the hood latch panels.
>Nice and smooth. Check my shutterfly pics for a shot of that. There is a
>fuel pump relay and cooling fan relay that I mounted on the firewall below
>the battery that are a part of the engine harness. I have the Check Engine
>light mounted where my ignition switch used to be and the connector for
>checking engine codes mounted right below the ash tray
>I made a custom stainless steel gas tank for under the bed and installed the
>stock fuel pump from the 85 gas tank to my gas tank. It is in the tank
>itself. I used the sending unit that came with my Auto Meter gauges for the
>This sounds like a lot but it isn't. Very easy to install and no special
>tools required. I suggest you go to: www.chevythunder.com for a wealth of
>info. This guy helped me a lot! He has harnesses and was the one to do my
>Please feel free to ask me anymore questions. If I can help, I will do my
>From: Roger.Gleason@uconn.edu [mailto:Roger.Gleason@uconn.edu]
>Sent: Friday, January 03, 2003 10:55 AM
>To: Jeff Engel
>Subject: RE: [oletrucks] Any more advice on IFS or Rear End swaps for TF
>I was wondering about the tuned port 305 with computer swap out of the
>IROC. Do you have any info on the required sensors, fuel pump/ relays etc
>required to do this swap. How easy is this swap. I have a 350 IROC totaled
>and would like to make that swap into my 51 AD. This IROC also has the disc
>brake rear end, that I think I can make work in it. I plan on installing
>the bolt in front suspension unit from a 73 1/2 ton Chevy P.U. with cross
>member and motor mounts.
>51AD 3100 Huckster
>I know you didn't inquire about this but I thought I would add some
>additional information on my drivetrain and my choices there. I had a 1985
>IROC Camaro that was totaled. So, I took the Tuned Port Injected 305 and
>700R4 tranny out of it and put it in my 56 TF. Computer and all. This
>gives me good mileage and performance. I also used the steering column and
>the front calipers. The overdrive tranny coupled with my 2.73 gears really
>helps on the highway. Low RPM, high gas mileage. I had 3.70 gears but they
>started to howl. So, I swapped the center section with another center
>section that I had from a different project (67 Mustang GT fastback). It
>drives much smoother with the 2.73's but not as snappy as the 3.70's.
>Another trade off to think about.
>I have some pictures of the front end, engine and truck on Shutterfly.com
>you want to take a look.
>I hope this gives you some of the info you needed and if not hopefully you
>weren't bored to tears!
>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959