'79 Caddy 425 with 454 TBI into a J-20

[Fury5]

Nice to see you found some time to make some progress. Looking good!

[jaber]

Thanks.
Just got my 4 core rad back from the shop. Had the ports switched for the GM configuration. Now I just have to figure out what I'm doing for a fan.

[jaber]

Well, lets see, I got everything back together last week end and used it 4 out of 5 days this week. I had to pull the t-stat out, as it was doing stupid things to the rad pressure. With no stat, it held about 200* at 70 down the hiway. Tues after work, it decided the fuel pump was not enough and was running crappy. I got it warranted through the Zone. It is running good for now.

I have a patch cord from the Custom EFIs kit I bought way back, but was not able to get the laptop to recognize the ECM. I think I am doing something wrong. Any advise is welcome. I have TunerPro on it.I can tell its running rich, and it bogs hard when you stomp on it. I have to turn the fuel down.

Best of all, IT LIVES AGAIN.........

Thanks for listening.

[PlasticBoob]

Originally Posted by jaber

I have a patch cord from the Custom EFIs kit I bought way back, but was not able to get the laptop to recognize the ECM. I think I am doing something wrong. Any advise is welcome. I have TunerPro on it.I can tell its running rich, and it bogs hard when you stomp on it. I have to turn the fuel down.

Best of all, IT LIVES AGAIN.........

Thanks for listening.

What a beast!!! Very cool! If you ever get some time, please let us know over in the EFI section how all your EFI stuff turns out. Are you running the 454 ECM as well? You're going to need a complete re-tune for the torque curve of this engine, including acceleration enrichments to make the most of this low-end torque monster. Unfortunately I have no experience with standard GM stuff so I can't be of much help.

[jaber]

This thing is wild to drive. I have only gone to 3K and it jumps right to speed.

Yes, its the 7747 GM computer. The whole system came from an '87 Suburban and I got everything. It did not have a knock sensor from the factory.

There is an ad in the home grown section for chips burnt to your specs and it has me in the ballpark enough, that I am DDing it 23 miles one way to work. I think I'm going to cut the other fender for a cold air set up.

I'm lost when it comes to the programing. I am going to have to do a lot of reading...

I did a stereo install today, and changed the rear output seal in the transfer case. I also noticed that the seals between the two are bad and they are swapping fluids.

[temps425]

I would consider that motor to be girthy and massive. Very cool build.

[jaber]

I got the laptop to recognize the ECM. it was showing me RPMs, temp, O2 reading,etc... That means I can datalog and work out this program.
Hope I can tune it to be the monster it could be. Stay tuned...

[Ristow]

Originally Posted by jaber

Stay tuned...

are you talking to us or the caddy?

[jaber]

Originally Posted by Ristow

are you talking to us or the caddy?

LOL, both.

[jaber]

Well, after 2 weeks, I have the first 500 miles on it.I have been playing with the timing a little and attempting to record data. TunerPro starts with a message box that says "mismatched ADS and XDF files". The ALDL dash shows all the readings from the engine. More to come as I get time to figure it out. Its probably user error.

[swampedge]

Where are you at with this now? Did the HEI distributor work correctly as a trigger for you? I'm in the process of putting the TBI into one of my Buick 350 powered Jeeps and was just curious as to how well you feel about your TBI installed on the Caddy engine.
Jim

[jaber]

I love the combo, I'm just having a hard time tuning. The dizzy is working perfect.

I bought a tune from a vendor and it is kicking my butt. I am going to attempt to start with a basic 454 tune and adjust it to my needs. The engine wants to run. She will cruise down the freeway at 70 all day long. I just need to find the "TBI Tuning For Dummies" book...

I have to admit, even with it running half-arsed, it still keeps up with new trucks off the line. I have a heavy foot, and it has no problem throwing all of its weight around. I'm anxious to get a set of 37" tires to help with freeway engine speeds.

Let me know if you need any other info...

[Bill USN-1]

Swampedge, You have been on BP and should have seen the HEI large cap conversion warning.
If using a factory large cap EFI distr you should be fine.
if trying to convert a carb version from the 4 pin to the 7/8 pin for use with EFI then you will have problems.
the rotor/reluctor phasing is different and will cause crossfire to the adjacent cap terminal.

If you don't understand then look at the duraspark conversion FAQ on the binderplanet and see where I drill a hole in an old cap to verify the phasing.
This is a must for proper operation.



Jaber- there are several basic tuning threads there also to help you get it dialed in. IF everything is installed and operating properly.

[jaber]

Bill, thank you for stopping in. Your sticky is what gave me the nerve to try this.
I must be doing something wrong here. I played with it today. I load a 454 BIN, AKDX Bin with a $42 XDF, into Tunerpro RT, go to Flags, uncheck the knock sensor, and the SES light starts rapidly flashing. No matter what code I run my SES light is always on.
Can I run a knock sensor from a Renix 4.0 and get the 7747 to recognize it?

For the record, this TBI came from an 87 suburban. I removed everything that was there, the system did not have knock sensor wiring. I have a tune that I bought, and the SES light is always on. When I jump it to get the codes, it gives me the knock sensor code. The flag is not checked in TP. If I try to change anything the SES light flashes rapidly until I return it.

Thanks for listening to me whine...

[Bill USN-1]

Not sure where your getting your bins from but the AKDX is a 7747- 4.3 auto bin.
It won't run your caddy very well.

Are you positive on the ECM number?
A lot of them from a 454 without knock were 8747.

Just making sure.

[babywag]

Originally Posted by jaber

Bill, thank you for stopping in. Your sticky is what gave me the nerve to try this.
I must be doing something wrong here. I played with it today. I load a 454 BIN, AKDX Bin with a $42 XDF, into Tunerpro RT, go to Flags, uncheck the knock sensor, and the SES light starts rapidly flashing. No matter what code I run my SES light is always on.
Can I run a knock sensor from a Renix 4.0 and get the 7747 to recognize it?

For the record, this TBI came from an 87 suburban. I removed everything that was there, the system did not have knock sensor wiring. I have a tune that I bought, and the SES light is always on. When I jump it to get the codes, it gives me the knock sensor code. The flag is not checked in TP. If I try to change anything the SES light flashes rapidly until I return it.

Thanks for listening to me whine...

Are you burning a new chip?
Rapidly flashing light is ECM trouble usually caused by an invalid BIN/bad chip, or ECM is in limp home mode.

[Bill USN-1]

If he has an error and can log data then the fault tab in winaldl will tell him the error or he can simply jumper pin A and b of the aldl connector and turn the key on to count the flashes.
But the ECM needs to be disconnected prior to any data log or the old codes remain for 50 starts.

I attached 2 bins.

Well I tried but I get a response that says a 3k file exceeds the quota by 1k.

So either I'm restricted from attaching zip files or there are issues the admin and mods need to address.

[jaber]

I guess that is not what I was looking for. I'm going to have to do more research. I get limited time on this and tend to loose my place and have to start over.
Thanks for your patience guys.

Originally Posted by Bill USN-1

I attached 2 bins.

Well I tried but I get a response that says a 3k file exceeds the quota by 1k.

So either I'm restricted from attaching zip files or there are issues the admin and mods need to address.

You can e-mail them to me.
aberw3az@hotmail.com

Thank you sir.

[Bill USN-1]

email sent.

[swampedge]

Thanks Bill. The reason I asked about the distributor was because of the phasing issues with them. Jaber are you not running a carburetor HEI distributor? I have the carburetor HEI that I wanted to use.
Jim