Tbi swap build thread

[rfmaster]

Originally Posted by 1984 t type

Ok so I'm going to go with the adapter plate with the 85 intake and heads. Is there going to be a special bracket for the tv cable ? Just trying to get my parts lined up
Posted via Mobile Device

There are couple of ways of solving TV cable bracket issues.

I have used Edelbrock 8036 kit - I do not know why Edelbrock designates for pre 78 intakes?

Existing throttle - trany kick down bracket (with spacers) and adjustable TV cable. Works OK if TBI to Carb intake adapter is 1/2" or less. Taller adapters screw up TV cable - throttle arm geometry - you have to raise bracket to maintain TV cable geometry, hence spacers.

Bowtie overdrives kit - expensive, but very nice kit. Works with carbs or if adapter plate is thin.

Carb brackets of various flavors are also known to work.

Correct TV cable - throttle arm geometry and correct adjustment of TV cable is a key to 700R4 longevity. Just my 2 cents.

//RF

[68 TT]

Originally Posted by 1984 t type

Ok so I'm going to go with the adapter plate with the 85 intake and heads. Is there going to be a special bracket for the tv cable ? Just trying to get my parts lined up
Posted via Mobile Device

You should be able to shim up the one from the 91 donor vehicle and make it work on your 85 intake with the TBI adapter.

Take some pictures & measurements of it on the 91 before you make the swap and shim it as needed to get the same distance from throttle arm and the same height relative to the base of the throttle body. This will get the proper amount of cable motion and the correct angle so everything works the way it is supposed to.

[1984 t type]

Who do u guys recommend that I get my Tbi adapter from ?
Posted via Mobile Device

[rfmaster]

Originally Posted by 1984 t type

Who do u guys recommend that I get my Tbi adapter from ?
Posted via Mobile Device

Probably the nicest CNC machined TBI plates that I have seen:

http://www.tbiparts.com/

He also carries a full assortment of TBI related parts.

//RF

[68 TT]

Originally Posted by rfmaster

Probably the nicest CNC machined TBI plates that I have seen:

http://www.tbiparts.com/

He also carries a full assortment of TBI related parts.

//RF

That one also addresses the common problems with many of the cheap adapters. Vacuum leaks because the TBI unit is partially over an intake mounting bolt location and insufficient flat area around the TBI unit to seal the IAC passage ways.

It is well worth the extra money to get the tbiparts adapter rather than try to save a couple bucks on a cheaper one and having to deal with problems.

[Cruz]

I have also posted this at the 3rd gen board....
Looking for thoughts or ideas on intake manifolds.

“75” 4 bolt block 9.5:1 compression (non TBI RV Cam can't remeber the specs currently)

194 cast iron heads ported and polished gasket matched.

89 TBI 7477 ECM running EBL with 14 psi fuel pressure

Currently running the 89 TBI intake modified to bolt to my cast iron heads.

I have recently acquired an RPM Air Gap manifold and was wondering if anyone has used this with the EBL and were there any performance gains/loss or other issues using this manifold? Since the Air Gap does not have a provision for an EGR will this affect anything with the GREAT mileage I am now enjoying?

Since converting my truck to fuel injection from a carb…… I have doubled my MPG from 10 to 21 MPG. All I can say is wow…. This is with running the TH400 in it now….. looking for a good 700R4 for the next project just to see what the mileage will end up…………..

Thanks for your input

Cruz

[1984 t type]

Ok gonna order that one. New problem, went to start removing the harness from my parts truck and it's not worth saving so who do you guys recommend for a aftermarket harness? Also what parts do I still need off the parts truck? I allready pull the computer and tbi unit
Posted via Mobile Device

[rfmaster]

Originally Posted by 1984 t type

Ok gonna order that one. New problem, went to start removing the harness from my parts truck and it's not worth saving so who do you guys recommend for a aftermarket harness? Also what parts do I still need off the parts truck? I allready pull the computer and tbi unit
Posted via Mobile Device

Can you post photos - it is tough to make recommendations without seeing the harness. Locally, in SoCal, due to the heat connector bodies crack, but these can be easily replaced. It is cheaper than R&R the whole harness. If there is a wire damage - that can be fixed with a solder joint and heat shrink. I come from electronic background and fixing harness issues is not a hard task, just requires some patience and correct materials.

If you are set on replacing your harness check out Fuel Injection Connection dot com on Ebay. Personally, I have reworked every single donor harness - I have never used aftermarket harness before. Perhaps someone else can chime in and suggest other sources.

You'll need all sensors
CTS - cheap to replace
O2 sensor - get a new one.
ESC module - works with knock (KS) sensor
KS - get a new one keep old one as spare.
Distributor & coil - 85 may have vacuum advance which does not work with EFI
MAP Sensor
EGR control valve
VSS - part of trany

TPS and IAC are in TB
FP relay

Do not forget to remove ALDL connector - driver side under dash.

//RF

[1984 t type]

Can someone post a schematic of the sensor locations. I may have jumped the gun saying the harness is shot it was in the 90's today and I was frustrated but I do have a couple of connectors that are ruined some were not even hooked up. Will post some pics later today or tomorrow. Thanks for the help
Posted via Mobile Device

[critict1gc]

ok so i need a heated o2 sensor for my hooker headers is there one in specific that i should get? can i just get any 3 wire bosch sensor off jegs. if there is a good one on jegs can someone tell me wich one

[Jonboy]

I used the FIC harness in my swap. The harness I had was pretty hacked up, so it was worth saving $245 of aggrivation to me to go with a new one. Not exactly shoestring budget, but not rediculously priced, either.

[rfmaster]

BOSCH makes fine O2 sensors, but GM ECM PID algorithm does not match very well with BOSCH S curve. Most of the time it will work OK, but sometimes you get funny close loop cycling between rich -lean condition. When I switched from BOSCH to AFS-74 problem resolved itself. AFS-74 heated 3 wire O2 sensor was used in a 95 S10 4.3L V6 GM part number 25312179 or 19178959 or ACDelco AFS-74 (or 213-632).

Rock Auto has 19178959 (AFS74) for about $50

//RF

[bagged74]

this is a great thread!! tons of info.
Do you guys have any experience with the 16197427 ECM? I am using the engine, trans and harness from a 94 truck. I have all the wiring sorted out except for one wire that doesnt seem to match the pinout diagram or the service manual that I have.

[rfmaster]

Originally Posted by bagged74

this is a great thread!! tons of info.
Do you guys have any experience with the 16197427 ECM? I am using the engine, trans and harness from a 94 truck. I have all the wiring sorted out except for one wire that doesnt seem to match the pinout diagram or the service manual that I have.

Which wire? We had a one gent that have transplanted 7427 PCM into 70 with 4 speed.

[bagged74]

the wire in question is in pin F8. the pinout and service manual show it should be gray/blk, but the wire I have is blue and runs down to a 2 pin weatherpak connecton that has a purple wire in it as well. the purple wire the runs to a plastic box with two diodes inside and two other purple wires coming out. i have no idea where these were connected as they were cut when i got the harness.
pin F8 shows to go to the 4wd indicator, but the truck was 2wd and had no 4wd indicator. any ideas?

[rfmaster]

GM used one harness design for both 2wd and 4x4 drive-trains. In 2wd application F8 is unconnected (gray/blk) wire. The box that you are describing is most likely an anti-lock diode module. This module should have two purple wires fed into Pin A. One of the two purple wires should be tied to TCC/Brake switch, while the other purple should be tied to Pin E13 of the PCM. The B port of the diode module is tied to 4x indicator and antilock module.

If you are doing 2wd transplant - leave this wire unconnected.

//RF

[bagged74]

Well I finished up my tbi swap today and drove it for the first time. It runs great, but I'm pretty sure the 3.07 gears are gonna have to go.
Posted via Mobile Device

[68 TT]

Originally Posted by bagged74

Well I finished up my tbi swap today and drove it for the first time. It runs great, but I'm pretty sure the 3.07 gears are gonna have to go.
Posted via Mobile Device

If you find a rear axle donor with gears you want and TBI then the DRAC will be right for the axle swap too. Vans came with 3.42 & 3.73 gears pretty commonly.

[dropd80s]

Finally got my CCSB pulled out of the shop under its own TBI'd power yesterday! Shes an 86 with a 90 sub TBI 350/700 and complete harness swap. Everything stock. My problem is she seems to be running very rich. I have considerable black smoke at idle. I have let the truck warm up to operting temp, and still have no codes stored. Everything is clear.

I am curious if the higher pressure fuel pump I ran (E2000) is overloading the FPR?
I know I need to check and make sure the 5/16" return line I ran is not kinked.
Also, I have no exhaust on the motor, only a few inches of pipe on the manifolds. Could this be cooling my 02 and not letting it read properly?
I assume this could also be a CTS problem or Vacuum leak?

Any ideas you guys have or how I should go about ruling things out would be a huge help. Thanks in advance

[rfmaster]

Originally Posted by dropd80s

Finally got my CCSB pulled out of the shop under its own TBI'd power yesterday! Shes an 86 with a 90 sub TBI 350/700 and complete harness swap. Everything stock. My problem is she seems to be running very rich. I have considerable black smoke at idle. I have let the truck warm up to operting temp, and still have no codes stored. Everything is clear.

I am curious if the higher pressure fuel pump I ran (E2000) is overloading the FPR?
I know I need to check and make sure the 5/16" return line I ran is not kinked.
Also, I have no exhaust on the motor, only a few inches of pipe on the manifolds. Could this be cooling my 02 and not letting it read properly?
I assume this could also be a CTS problem or Vacuum leak?

Any ideas you guys have or how I should go about ruling things out would be a huge help. Thanks in advance

Yes, all of the above can potentially cause rich condition. Make sure that your harness has ALDL connector wired and SES is functional. If your ECM sees open CTS it will set Code 15 (very cold temperature = rich fuel mixture!) Jumper Pin A&B of ALDL and read SES blinks.

I would go through the check list first before jumping to any conclusions.

1) Verify operating fuel pressure by measuring FP at the input port of the TB with a fuel pressure gauge. That should take care of E2000 pump and 5/16" return line. You should see solid 13 to 14 PSI. Stock regulator can handle 40 PSI pump without too much trouble.

2) Non functioning CTS or an open ground lead will cause rich condition.

3) I am going to assume that you have cast iron (CI) exhaust manifolds - these should be adequate to keep your O2 hot (around 600F), but a full length exhaust system should be put in eventually.

//RF

[dropd80s]

The ALDL and SES light are both functional. I have checked for codes and only get the code "12", so I am good there.

I will check the fuel press. and see what it shows.
The CTS is just a switch correct? This should be easy to check.
And yes I have stock exh. manifolds still. Just got to get her to the muffler shop to get the exhaust ran.

Thanks for your help.

[rfmaster]

Originally Posted by dropd80s

The ALDL and SES light are both functional. I have checked for codes and only get the code "12", so I am good there.

I will check the fuel press. and see what it shows.
The CTS is just a switch correct? This should be easy to check.
And yes I have stock exh. manifolds still. Just got to get her to the muffler shop to get the exhaust ran.

Thanks for your help.

CTS is NOT a switch - it is a thermistor. Basically a variable resistor that changes its resistance value with temperature. A typical AC-Delco CTS will be 99.3 kOhm at -40C; 9.25 kOhm at 0C (32F); 2.75 kOhm at 25C; 175 Ohm at 100C. ECM uses ADC to measure voltage drop across CTS to determine corresponding coolant temperature.

//RF

[dropd80s]

Originally Posted by rfmaster

CTS is NOT a switch - it is a thermistor.

Ok now I think you're just making words up as you go along . I understand now. I'll check to make sure the CTS is also working correctly.

Thanks again.

[rfmaster]

Originally Posted by dropd80s

Ok now I think you're just making words up as you go along . I understand now. I'll check to make sure the CTS is also working correctly.

Thanks again.

Occasionally I slip-up, but not this time....

http://en.wikipedia.org/wiki/Thermistor

[cheepin]

So this thread is awesome and I got my 454 TBI running in my Crawler.But it spun a bearing and ate the caps pretty damn good.I have a running SB400 I want to swap in.What do I need to do to for the TBI to run it correctly?The swapped in comp and harness is from an '88 crewcab 1ton.It's a short deck 454 so the dist. should work correct?