93 4.3 CPI to Smallblock V8 TBI
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lockdoc
Topic author - I sleep in my van
- Posts: 704
- Joined: Tue Sep 19, 2006 4:50 am
- Location: Plymouth Township, PA
What a freakin day! Murphy was with me the whole time. I got everything rewired, extended wires, added wires ect. All soldered and shrink tubed. Did everthing that needed to be done in order to try and start the engine. Here is how it went:
1. No fuel pump. Checked voltage at the wires. All was good. Figured the new/used pump I put in went bad while in storage. Of course I was too stupid to check it. Removed tank AGAIN to replace the pump. Find the ground wire was a liitle cooked from a previous pump. Rewired and put a new pump in anyways. I checked the pump. Put it all back together. NO PUMP! Long story short I find a cracked\broken wire in the harness under the van. Just what I wanted. MORE wiring! FIXED
2. Crank it over. No spark and no fuel coming from the injectors. Again, long story short, the distributor was bad and the one I picked up a couple weeks ago doesn't fit. But at least it let me know the cause of no spark\injectors.
3. Only one injector is firing. I quadzillioned checked my (RE) wiring for that injector. Everthing is as it should be according to the GM FACTORY MANUAL! The schematics told me pin out\wire A9 in for injector B on a Z engine and on a W it goes to the variable tuning relay and that is the wire I used. Again, long story short, A9 had no wire in it and the W motor wire I was using was E3. Go figure. So I repinned the ECM for that wire.
4. I connected my fuel pressure tester to check out if I have the right fuel pressure. Hook it up, turn they key and I'm immediately sprayed with a large dose of gas. Seems the seals in the adapter are shot. That's OK I say! I have a new one that I forgot about. Cool! NOT! Take the above sentence times two.
5. I still don't have the proper chip for my ECM. I could only find one at the junkyard for a 350. Figured I'd at least start it with that prom untill I get the right one. Again, I was wrong. All it does is flood the engine. Have to wait for the right chip.
So anyways, I'm exhausted.
1. No fuel pump. Checked voltage at the wires. All was good. Figured the new/used pump I put in went bad while in storage. Of course I was too stupid to check it. Removed tank AGAIN to replace the pump. Find the ground wire was a liitle cooked from a previous pump. Rewired and put a new pump in anyways. I checked the pump. Put it all back together. NO PUMP! Long story short I find a cracked\broken wire in the harness under the van. Just what I wanted. MORE wiring! FIXED
2. Crank it over. No spark and no fuel coming from the injectors. Again, long story short, the distributor was bad and the one I picked up a couple weeks ago doesn't fit. But at least it let me know the cause of no spark\injectors.
3. Only one injector is firing. I quadzillioned checked my (RE) wiring for that injector. Everthing is as it should be according to the GM FACTORY MANUAL! The schematics told me pin out\wire A9 in for injector B on a Z engine and on a W it goes to the variable tuning relay and that is the wire I used. Again, long story short, A9 had no wire in it and the W motor wire I was using was E3. Go figure. So I repinned the ECM for that wire.
4. I connected my fuel pressure tester to check out if I have the right fuel pressure. Hook it up, turn they key and I'm immediately sprayed with a large dose of gas. Seems the seals in the adapter are shot. That's OK I say! I have a new one that I forgot about. Cool! NOT! Take the above sentence times two.
5. I still don't have the proper chip for my ECM. I could only find one at the junkyard for a 350. Figured I'd at least start it with that prom untill I get the right one. Again, I was wrong. All it does is flood the engine. Have to wait for the right chip.
So anyways, I'm exhausted.
Lockster, I think I brought this bad juju on you. See, I finally got my exhaust system all plumbed correctly--cat and all-- and actually pulled it off in two days with a minimum of cussin' and blood letting. Even got it done just before the rain started.
So you see that there was a cosmic balance to set right after all that and you happened to be in the wrong place at the wrong time.
I think I owe yo a coffee.
So you see that there was a cosmic balance to set right after all that and you happened to be in the wrong place at the wrong time.
I think I owe yo a coffee.
Rob Shaver
1989 Astro 305 with an MSD 6A ignition and a dash-mounted MSD timing control, a 4160 Holley 465 cfm four barrel carb, and an HEI distributor.
Moog 625 front springs and Energy Suspension poly bushings. Rear OEM sway bar. Edelbrock shocks.
1989 Astro 305 with an MSD 6A ignition and a dash-mounted MSD timing control, a 4160 Holley 465 cfm four barrel carb, and an HEI distributor.
Moog 625 front springs and Energy Suspension poly bushings. Rear OEM sway bar. Edelbrock shocks.
lockdoc: I've been following your engine swaps for some time now with great interest. I'm glad you are taking on the CPI to V8 swap. I've always wondered if it would be easier to modify the CPI harness or just to replace it with a TBI wiring harness. I live in California and will have to have a smog referee look over my installation. They insist that all the correct smog equipment be in place which means vacuum controlled EGR valve instead of the linear EGR valve. The other requirement is that all unused wiring must be removed from the harness. I'm not afraid to unwrap my entire engine control harness modify and re-wrap it, but I might use the CPI motor in my 65 Chevy van because it still runs well.
I really enjoyed your page on the 4L60E rebuild. I have a holding fixture that fits in my engine stand to hold the transmission with the tailhousing down that makes rebuilding them easier. I like those Tech Tran books. They are very easy to follow.
I really enjoyed your page on the 4L60E rebuild. I have a holding fixture that fits in my engine stand to hold the transmission with the tailhousing down that makes rebuilding them easier. I like those Tech Tran books. They are very easy to follow.
95 Astro 4.3 4L60E 3.42 Bilsteins/Timbrens
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
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lockdoc
Topic author - I sleep in my van
- Posts: 704
- Joined: Tue Sep 19, 2006 4:50 am
- Location: Plymouth Township, PA
I'll eventually post all the wiring when I know it works but there are only a few wires left over that don't do anything. Two out of four wires at a relay, three out of five wires that went to the linear egr, one knock sensor wire and the two wires that went to the IAT. All easily capped and bundled back in the harness where no one can see them or know they are there. But there are around a dozen wires that need to be extended. When done, my engine and compartment will be the equivelant of a 93 C1500 with a 305 TBI \ 4L60E.
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lockdoc
Topic author - I sleep in my van
- Posts: 704
- Joined: Tue Sep 19, 2006 4:50 am
- Location: Plymouth Township, PA
Update:
Almost done. Extended the steering shaft and shifter linkage.
Installed the Taurus fan.
Modified stock exhaust to fit.
A gazillion other things I can’t recall right now.
All that is left is to install the correct chip, bleed the brakes and steering, wire in the fan, extend the front bumper mounts and install semi custom bumper.
Almost done. Extended the steering shaft and shifter linkage.
Installed the Taurus fan.
Modified stock exhaust to fit.
A gazillion other things I can’t recall right now.
All that is left is to install the correct chip, bleed the brakes and steering, wire in the fan, extend the front bumper mounts and install semi custom bumper.
Lookin' good, Bill.
Hey, what's that I see connecting up to the passenger side exhaust manifold, flex pipe?
Hey, what's that I see connecting up to the passenger side exhaust manifold, flex pipe?
Rob Shaver
1989 Astro 305 with an MSD 6A ignition and a dash-mounted MSD timing control, a 4160 Holley 465 cfm four barrel carb, and an HEI distributor.
Moog 625 front springs and Energy Suspension poly bushings. Rear OEM sway bar. Edelbrock shocks.
1989 Astro 305 with an MSD 6A ignition and a dash-mounted MSD timing control, a 4160 Holley 465 cfm four barrel carb, and an HEI distributor.
Moog 625 front springs and Energy Suspension poly bushings. Rear OEM sway bar. Edelbrock shocks.
Bill, I just snagged an engine wiring harness from a 93 TBI Astro for $30 at the junkyard. What an octopus! I worked on it for two days getting it out. I was down to the last few connectors when the foreman came out and asked me what I was doing. I told him that the owner and I talked about it and had set the price before I started disconnecting it. The foreman told me that he hadn't had a chance to test run the engine yet. I wanted to say something nasty like, "Who's fault is that?" but I decided to be nice about it.
Is your 305 conversion running yet? I had a guy around the corner call me wanting to sell me his 86 Trans Am really cheap. The motor runs well, but the car has a lot of non-professional body work done to it. He let me listen to it run while he reached in the glove box and pulled out a small notebook with all his maintenance recorded in it. The engine itself looks really clean and has had a recent valve job. I was thinking about using that motor in my Astro. I have a completely disassembled LO3 motor (305 TBI) in my storage building. I was thinking of converting the 86 LG4 motor over to an LO3 which would be smog legal to use in my 95 van. The car even comes with a factory electric fan I figure I could mount to my radiator easily.
The main reason I want to do my V8 swap is that I'm not really satisfied with the passing performance of my 4.3 CPI motor. It runs really well down low, but when I'm passing at higher speeds above 60 mph it runs out of breath. I guess the whole point of all of this can be boiled down into one question. In your opinion, is the 305 a worthwhile swap over the 4.3? When I get the money saved up for a 383, that's what I want in there. For the mean time however, I could swap in the 305 and use that motor to get my engine change approval from the smog referee.
Is your 305 conversion running yet? I had a guy around the corner call me wanting to sell me his 86 Trans Am really cheap. The motor runs well, but the car has a lot of non-professional body work done to it. He let me listen to it run while he reached in the glove box and pulled out a small notebook with all his maintenance recorded in it. The engine itself looks really clean and has had a recent valve job. I was thinking about using that motor in my Astro. I have a completely disassembled LO3 motor (305 TBI) in my storage building. I was thinking of converting the 86 LG4 motor over to an LO3 which would be smog legal to use in my 95 van. The car even comes with a factory electric fan I figure I could mount to my radiator easily.
The main reason I want to do my V8 swap is that I'm not really satisfied with the passing performance of my 4.3 CPI motor. It runs really well down low, but when I'm passing at higher speeds above 60 mph it runs out of breath. I guess the whole point of all of this can be boiled down into one question. In your opinion, is the 305 a worthwhile swap over the 4.3? When I get the money saved up for a 383, that's what I want in there. For the mean time however, I could swap in the 305 and use that motor to get my engine change approval from the smog referee.
95 Astro 4.3 4L60E 3.42 Bilsteins/Timbrens
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
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lockdoc
Topic author - I sleep in my van
- Posts: 704
- Joined: Tue Sep 19, 2006 4:50 am
- Location: Plymouth Township, PA
It is in and running Astro95. Here is a link on AS.com. http://www.astrosafari.com/cgi-bin/ikon ... =9;t=18198 I still need to post it over here but untill then...
If you are going TBI I highly suggest going with a 350 if you can get one. If not, the 305 will be better than the 4.3 but you will want more quickly. The only problem I see with a 93 harness is the tranny connection. The 95 4L60E started using PWM (pulse width modulated) torque converter lockup. The 93 harness may not have the appropriate wires. Worst case is you add them I guess.
If you are going TBI I highly suggest going with a 350 if you can get one. If not, the 305 will be better than the 4.3 but you will want more quickly. The only problem I see with a 93 harness is the tranny connection. The 95 4L60E started using PWM (pulse width modulated) torque converter lockup. The 93 harness may not have the appropriate wires. Worst case is you add them I guess.
That's a good point you brought up. I have two schematics from All Data. One is from the 95 Astro and the other is a 95 C1500 pickup which is the authorized donor vehicle to make my conversion smog legal. The C1500 schematic shows an extra wire from the PCM to the tranny. My diagram isn't very good. I shows the extra wire from pin F8 on the PCM going to the tranny connector, but doesn't give the pinout at the tranny. I can always add that wire to the harness, but if it doesn't do anything at the tranny end, I may still pop a DTC. Do you know what that particular one controls?
Something interesting also. When I compared my 95 Astro schematic to the PCM connectors on my 93 harness, I noticed that all the required wires were present. I even found one (E8) that was missing from the 95 Astro schematic in the 93 harness. It was a yel/blk wire and was present on the C1500 diagram. So unless I'm mistaken, the 93 and 95 Astro harnesses have the same PCM to tranny connections. (Both are missing the wire from pin E8 however) My smog referee told me that I must use the correct computer which means the one for a 95 C1500. He told me that he will be verifying the service number on the PCM.
Something interesting also. When I compared my 95 Astro schematic to the PCM connectors on my 93 harness, I noticed that all the required wires were present. I even found one (E8) that was missing from the 95 Astro schematic in the 93 harness. It was a yel/blk wire and was present on the C1500 diagram. So unless I'm mistaken, the 93 and 95 Astro harnesses have the same PCM to tranny connections. (Both are missing the wire from pin E8 however) My smog referee told me that I must use the correct computer which means the one for a 95 C1500. He told me that he will be verifying the service number on the PCM.
95 Astro 4.3 4L60E 3.42 Bilsteins/Timbrens
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
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lockdoc
Topic author - I sleep in my van
- Posts: 704
- Joined: Tue Sep 19, 2006 4:50 am
- Location: Plymouth Township, PA
F8 was not used for 93-94 models. That is all I know as my schematics only go to 94.
E8 is for shift solenoid B which is used on all. It is pin B on the tranny connector. It is yellow\black.
It seems that all you need to find out is what pinout on the ECM is for the PWM solenoid in the tranny and what pin that is on the tranny connector.
Out of the 19 pinouts on the tranny plug, 12 are used in 93-94.
The pins are: ABCDELMNPRST. I would venture to guess that if you find a 13th, that will be the PWM. I believe it will be a solid BROWN wire. Find that brown wire at the ECM as it sits now and you got it!
I'll have to go find the lit I had on the 95 tranny to see if I missed anything. I know at some point they got rid of the 3-2 shift solenoid.
E8 is for shift solenoid B which is used on all. It is pin B on the tranny connector. It is yellow\black.
It seems that all you need to find out is what pinout on the ECM is for the PWM solenoid in the tranny and what pin that is on the tranny connector.
Out of the 19 pinouts on the tranny plug, 12 are used in 93-94.
The pins are: ABCDELMNPRST. I would venture to guess that if you find a 13th, that will be the PWM. I believe it will be a solid BROWN wire. Find that brown wire at the ECM as it sits now and you got it!
I'll have to go find the lit I had on the 95 tranny to see if I missed anything. I know at some point they got rid of the 3-2 shift solenoid.
Bill, I got my info off the Auto Zone website. I noticed it has some inaccuracies, so I don't trust it. That brown wire that you mentioned may be the 13th wire that goes to pin F8 on the PCM. I wouldn't think that they would use two different transmission control systems for 95 Astro vs 95 pickup. If I have to trace out every wire in the harness, I'll do it to keep from burning something up.
95 Astro 4.3 4L60E 3.42 Bilsteins/Timbrens
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
410,000 miles and counting
65 Chevy van 90" WB 305 700R4 3.36
garage queen rescued from the crusher many years ago
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lockdoc
Topic author - I sleep in my van
- Posts: 704
- Joined: Tue Sep 19, 2006 4:50 am
- Location: Plymouth Township, PA
The 96 and up two piece tranny is designed to go with the new engine block\oil pan setup. You will need to fabricate a dust shield. there also may be another wiring difference but I'm not sure.BLAZER wrote:This is some good stuff!!! I am doing the exact same swap as you Astro95, using a 95 c1500 truck to go into my 95 stro....so hurry up and get yours done so I will know how to do mine
The onlty difference I have, I will be using a 96 tranny so hopefully it's not too much different.