Xephius's unnoffical LT1 conversion thread.

[Rebel]

I'm with Stan on that one. Always an issue here and there with a swap and need some local miles on it before going long.

[Xephius]

Well, I would love to make the swap after the trip, but its not an option. I have a knock in the motor, best I can tell a collapsed lifter and not a lower end knock. But we really won't know until I pull the V6 down and check it out. Once I heard the knock, I parked the van. This is what prompted the swap happening now.

In 3 weeks I have an event with my Living History group, several thousand of us get together and geek out. I am hauling out my camper and a boat load of fighting equipment so I really need the van. My hope was to get the motor back and in next weekend giving me a week or so to trouble shoot any gremlins.

One advantage I have going for me is a professional Corvette mechanic and a full shop to do the motor reassembly and install. The floor lift should speed things up. All that being said, I am still needing help with the A/C and accessory mounts.

I searched the old forums and found some obscure references saying that the factory Firebird/Camaro compressor hangs too low on a 4WD. But does it hang to low on a 2DW?

And finally, I have been doing some research on the cooling of the LT1 in the van. The guys at Jags that Run said that the LT1 will have trouble cooling when towing. They said that without mechanical fans it just won't pull enough air, specially for the Houston heat. He suggested that I get a Caprice LT1 towing package fan kit. This is a mechanical fan that adapts to the LT1, but is a little offset. For those of you who do have the LT1 installed, how much room is left between the front of the block and the radiator? Is there room for a mechanical fan to sit in there?

Thanks,
-=John=-

[HPbyStan]

On the LS1, You have to relieve the cross member a bit to clear the A/C compresser... I think the same will be true with the LT1 but not sure. My LS1 cools just fine with '97 Z28 dual fans and relays. There again, not sure about the LT1. The Z28 setup nearly is a "bolt in" on a '96 or newer 'Stro once,again, not sure about a '95. Good Luck at any rate.

[Xephius]

Did you use the Astro rad or the Camaro rad with the fans?

[HPbyStan]

Used the Astro radiator. The '96 and newer is thinner but wider. You get more clearance and better cooling and it this thing that the Z28 dual fans look like they were made for it. The '95 is kinda a "in between year" and I don't know which rad you have...

[peter]

I generally agree with the use of mechanical fans. I run twin electric fans on my truck, but not by choice. Flex-a-lite 27" twins flowing around 4600 cfm. The rad is a single-row 1.25" thick corvette core using my OEM tanks. Core cost me approx. $150 & bolts right in! Truck stays cool in any weather, but if towing the Tramper (approx. 2500 lbs loaded) thru hilly regions in summer at low speeds for extended periods of time, temps get into the 210-215's. Still not earth-shattering, but I don't like it. If I was towing 4-5k lbs and in the same hilly areas, I'm sure I'd be screwed.
I know that Neil (LS1AWD) also runs stock LS1 electric fans just like Stan. He is also very happy with the cooling of his truck. However, I don't think he's ever towed 4-5K lbs in hilly regions with it either. If he or Stan has and they don't have an issue with overheating, then forget everything I just typed.

[HPbyStan]

On my Tx / Cali / and home trip last fall pulling a big a$$ed trailer we had some over heating problems on I-10 in west Texas and I'm cursing electric fans BUT it turned out the relay for the second fan had failed and it was cooling with only one fan. 80 mile an hour speed limit and I had to drive 60 untill we figured out the problem. So I still don't know for sure if everything would have been OK if both fans were working. Course it's an all aluminium 5.7 V8 and not a 502 cu.in. hunk of cast iron

[peter]

Yeah, and you were going 60 mph. One would think you wouldn't need any fan operation at that speed. But it's been proven that there are times where the fans are needed at even higher speeds. I'm anxious for you to try again with the repaired relay issue.
However, GM now sells 1/2 ton pick-ups with dual electric fans. A loaded 1/2 ton towing a trailer is NOT gonna be an uncommon sight or situation, right? Mind you, the rads on 1/2 ton pick-ups are 31-32" wide as compared to our 27".

[91AWDAstro]

Yep, our 06 Silverado has dual electric's in it. This is still a concern for me on cooling on my truck, (truck?... don't we mean van Peter?) since I finished up my swap in the fall and haven't really had any summer weather driving with it. Next summer and some serious AC use should determine weather or not I'll have any issues.

Good luck with the swap.

[mikedamech]

Well, I would love to make the swap after the trip, but its not an option. I have a knock in the motor, best I can tell a collapsed lifter and not a lower end knock. But we really won't know until I pull the V6 down and check it out. Once I heard the knock, I parked the van. This is what prompted the swap happening now.

In 3 weeks I have an event with my Living History group, several thousand of us get together and geek out. I am hauling out my camper and a boat load of fighting equipment so I really need the van. My hope was to get the motor back and in next weekend giving me a week or so to trouble shoot any gremlins.

One advantage I have going for me is a professional Corvette mechanic and a full shop to do the motor reassembly and install. The floor lift should speed things up. All that being said, I am still needing help with the A/C and accessory mounts.

I searched the old forums and found some obscure references saying that the factory Firebird/Camaro compressor hangs too low on a 4WD. But does it hang to low on a 2DW?

And finally, I have been doing some research on the cooling of the LT1 in the van. The guys at Jags that Run said that the LT1 will have trouble cooling when towing. They said that without mechanical fans it just won't pull enough air, specially for the Houston heat. He suggested that I get a Caprice LT1 towing package fan kit. This is a mechanical fan that adapts to the LT1, but is a little offset. For those of you who do have the LT1 installed, how much room is left between the front of the block and the radiator? Is there room for a mechanical fan to sit in there?

Thanks,
-=John=-

The knock could be the dampner pully. I replaced a supperchager on a 3800 just to find out the balancer pully was the noise.

[Xephius]

I will check the balance tonight, but based on the way the noise is occuring I doubt it. I am still going to put in the V8, but this would buy me some time...

Thanks!

[tbhager94]

did ya ever get that v8 in there and running???????????

[mikedamech]

Well I'm wording on mine. I have a lot done, Lot's more to do. Motor and tranny are in and under vehicle, drive shaft in, dip sticks in, Headman headers on, Exhaust crossover pipe made but off cuz the front is lowered for access. All wiring is done up to the front of engine, I have to connect wires to fuse-relay box and C100 Bulkhead Connector. The fuel system - wiring is in, I used the plastic fuel lines from the Caprice and made a Cool device to hold the plastic while using my press made it so easy. I clamped too 2X4s together and drilled a hole down the seem 2 drill bit sizes smaller and a hole 2 sizes bigger 1", clamped the line even with the top and pressed the coupler fitting in the tube, put the other line in the contraption and grabbed the center of the fitting and pressed with my hands and the fitting went on easily, never use the hot water thing again.
The power steering lines are not done, I have to lengthen the pressure line to reach the Hydro boost, and connect the battery cables and see if she runs. I have some questions for those of you who put in LT1's the oil low and oil change lite not having one on the astro.

[Xephius]

Well, I am back from my vacation and about to dive back in on the van. I too have the motor in place in in the van but realized the headers hit on the driver side floor pan. I am going to lift it up, bang out some room and put it back tomorrow. I also hope to have all the wiring in place so I can start her up this week. More as it comes.

[Rebel]

Post some pics. you know we can't sleep at night with all this going on and no pics.