anyone did do or planing on doing a TBI conversion on your K5/Jimmy

[Jason915]

I am in the process of doing the TBI conversion to my K5 and will post progress pictures and report everything I can. I was just courious if anyone in this to your 1st gen K5/Jimmy. I remember someone in this fourm that was thinking about it but I cannot find the post.

[hotrodmtodd]

I have had a Holley Pro-Jection setup on a shelf for about 12 years. I picked up a 72 Blazer recently for a DD and am SERIOUSLY considering breaking it out of the box for this baby. I will be following your progress. Good luck to you, Mike

[pound41]

I think it was Mike S in Charlottesville VA did one last spring and posted pic you can try searching for him. I haven't seen him on here in a while

[vtblazer]

I'm doing a TPI this summer.

Yes there was a recent post on it, did you try search yet?

[72freak]

I did the TBI to my 72 Suburban. I used the complete running gear from a 1990 Suburban. Engine, trans., and front to back harness. Hooking up the dash was the only time consuming part. I would recomend using a COMPLETE donor vehicle instead of trying to piece it together. MUCH easier and quicker.

[Scrubby]

I really want to do a TPI with MegaSquirt. Check it out. Do it yourself EFI electronics. http://www.msefi.com/

[Jason915]

Ok I am at the parts collecting stage right now I have:
TBI intake, throttle body, all intake mounted sensors, knock sensor, inline throttle body injection Holley fuel pump, Painless vehicle speed sensor, FI distributor & coil, cpu,
I still need a wiring harness

my delima right now is should I get an 87-95 longblock so everything works on this like a production vehicle, or should I build my own motor using better heads and cam then get a chip to compensate?

72freak how did you run your return line to the gas tank?

[smokekiki]

Originally Posted by vtblazer

I'm doing a TPI this summer.

Yes there was a recent post on it, did you try search yet?

Me too.I have a TPI unit all cleaned and ready.The harness was cut in 2 places.I either need to solder it back together,build a new harness,or buy one.

[vtblazer]

Originally Posted by smokekiki

Me too.I have a TPI unit all cleaned and ready.The harness was cut in 2 places.I either need to solder it back together,build a new harness,or buy one.

I think I've decided to go with a stand alone comp. set up.
I do have the factory stuff but the stand alone seems alot easier.

[Jason915]

Yep I am doing a stand alone set up that way I can have my harness built for everything that I am using and not a mess of wires for stuff I am not going to use. I was also thinking about going TPI but found that most prefer the TBI for 4 wheeling and off road becasue it idles lower and has more bottom end grunt. Either way fuel injection is going to be nice to have.

[smokekiki]

It depends who you talk to about Tpi vs tbi.Others will tell you tpi is better off road.It makes more power at lower rpms.A stock tpi will run out of breath at 4500-5000rpm.

[70rs/ss]

The tbi is just like a carb except no fuel bowls to over flow so they work good all around. I'd guess the TPI is great and most of do not turn much over 5k in our trucks. I will be using an LT1 in my Camaro, and possibly an LS1 or 5.3 in my Blazer (maybe!) I own the LT1 already, but the LS1/5.3 are still a little pricey. I'll use painless kits on all because factory stuff is redundant in our years because all of the emissions crap etc. TPI.com I think is the web address for a place in Phoenix, az and they can cut up and thin the factory one, but it is nearly as expensive as the painless kit. One more thing, my wrestling coach from HS (class of 90 rocks!) had a K5 with projection on it and a half top as well. I know how cool it was then, but now it is my dream, BTW he hunted and wheeled it liked crazy and claimed the projection worked when the truck was upside down!!

[MikeS]

Originally Posted by pound41

I think it was Mike S in Charlottesville VA did one last spring and posted pic you can try searching for him. I haven't seen him on here in a while

Yeah, it was me. I did the TPI conversion last summer. The TBI conversion process should be a little easier actually. If you aren't going with one of the aftermarket units, the best thing you could do is find an entire donor truck, park the two sided-by-side and just swap the parts over.

[Jason915]

Originally Posted by MikeS

Yeah, it was me. I did the TPI conversion last summer. The TBI conversion process should be a little easier actually. If you aren't going with one of the aftermarket units, the best thing you could do is find an entire donor truck, park the two sided-by-side and just swap the parts over.

That would have been ideal, and I was originally looking for a truck or van to use as a donor vehicle but didn't find anything I was interested in. My Blazer needs a new engine so I may just order a longblock for a 87-95 TBI truck. How's your TPI run, did you notice a power increase and an MPG difference?

[bpmcgee]

I installed a Holley Pro-Jection system in my truck last year. This year I'll be converting to the Holley Commander system.

The most difficult part of these conversions is the fuel pump, to be honest. Everything else was pretty straightforward.

Brian

[MikeS]

Originally Posted by Jason915

That would have been ideal, and I was originally looking for a truck or van to use as a donor vehicle but didn't find anything I was interested in. My Blazer needs a new engine so I may just order a longblock for a 87-95 TBI truck. How's your TPI run, did you notice a power increase and an MPG difference?

I love the TPI. Low end power is great. I probably got a 1.5-2 mpg increase but you don't do these things for the mpg. The driveability is really improved. Great throttle response and it starts right up no matter how cold it is. Besides, the looks of the TPI gives it a serious wow factor.

I'm not sure what kind of fuel pump you need for TBI, but I put in an in tank unit from Tanks, Inc http://www.tanksinc.com/index.cfm/pa...prod/prd84.htm

The only problem I had with it was that it didn't sit deep enough in the tank and so I had to extend it a bit.

[Musclerodz]

I will be installing a 400hp Lt-1 in my Blazer as soon as the drivetrain is complete. Already had it for another project so I just stole it for the Blazer. I would recommend an intake pump. They are less trouble than an inline pump and are more expensive to do. I will have a Stainless tank made by Rick's Hot Rod Shop when I get that far specifically for the Blazer.

Mike

[tpi72blazer]

Regardless of whether or not you go TBI or TPI, do yourself and get an aftermarket wiring harness. It greatly simplifies the installation, makes it look cleaner, and can be setup to your type of system. My TPI unit came from an 88 IROC so it was a mass air type. I converted it to speed density for reliability.

[SB406]

My 71 GMC is TBI (SBC 406). If you tune your own chips, you can do pretty much whatever you want with it......set idle speed, adjust timing, adjust pump shot, etc, etc....The biggest problem I ran into was the fuel pump. The factory tanks in these trucks are not baffled. So, you get fuel sloshing away from the pump. This not only heats up the pump (The gas cools an in-tank pump) but it also starves it on fuel momentarilly. I ended up running a Russel bulkhead out of the bottom of the tank to a frame-mounted fuel pump. The other problem with an in-tank fuel pump with a pickup is the noise of the pump running will drive you nuts! I used the harness from an 88 chevy van (ECM #1227747). The same harness is used for 4.3L, 5.7L, & 7.4L truck motors.

The main idea for adapting in any factory harness is to run the motor off the Fuel injection harness. You run the harness from your controls (ignition, gauges, etc)

[ecameron87]

I did the Holley ProJection and I love it. It is easy to do and the power and throttle response is much better than the quadrajet. I even get slightly better gas mileage!

[Jason915]

Originally Posted by SB406

My 71 GMC is TBI (SBC 406). If you tune your own chips, you can do pretty much whatever you want with it......set idle speed, adjust timing, adjust pump shot, etc, etc....The biggest problem I ran into was the fuel pump. The factory tanks in these trucks are not baffled. So, you get fuel sloshing away from the pump. This not only heats up the pump (The gas cools an in-tank pump) but it also starves it on fuel momentarilly. I ended up running a Russel bulkhead out of the bottom of the tank to a frame-mounted fuel pump. The other problem with an in-tank fuel pump with a pickup is the noise of the pump running will drive you nuts! I used the harness from an 88 chevy van (ECM #1227747). The same harness is used for 4.3L, 5.7L, & 7.4L truck motors.

The main idea for adapting in any factory harness is to run the motor off the Fuel injection harness. You run the harness from your controls (ignition, gauges, etc)

Thanks for the feedback, I have already purchased an inline Walbro low pressure fuel pump it came with a heavy duty thick rubber insulator and nice clamps that are also insulated so I am hoping for minimal noise. I have a fresh .40 over 350 and some rebuilt 083 cylinder heads I will be going with a Crane 2030 cam. Do you tune your own chips? Do you have an adjustable FPR? How do you get set up to tune your own chips? I was just going to try to get it running with a mechanical tune at first then once it was running I was going to contact someone that could make a custom chip for me. I am expecting about 270~ HP and 350~ FT LBS what do you think?

[SB406]

Sounds like you're on the right track. What pressure is that pump? My TBI runs on 15psi. Some of the 454 TB's run on higher pressure. I made my own fuel pressure regulator
Tuning chips isn't as bad as it sounds. I got all of my equipment here: http://moates.net
Some Great information can be found here on the TBI, TPI, and DIY PROM boards: http://thirdgen.org

Lastly, to get started, read this: http://http://www.thirdgen.org/promintro

Hope this helps.
-Mike

[Jason915]

I think my pump will run from 10-18 psi. Thanks for the info.

[69sixpackbee]

Theres a Megasquirt TBI system on Ebay right now.