Which auto on LS1 HQ

[SteveHQ]

I've been toying for a while with the idea of putting a LS1 into my HQ project and managed to pickup a VZ manual SS with low kms for the donor fairly cheap. I'd like to get rid of the manual and put in an auto but was hoping to leverage some of the knowledge here on what's involved in my options..

1. 4L65E - I know these will fit in the HQ tunnel, but what is needed to be changed on the manual loom from the VZ?
2. TH350/400 - These were stock in the HQ - but what is involved in getting this working with the LS1 ?

Any insight into the pro's and con's of these (or any others) and info on what can be re-used from the VZ gratefully received.

Cheers,
Steve

[white lie]

Depends what the purpose is. T400 will be a lot stronger if you're looking to make some decent power and easy enough to get working behind the LS1.
If you just want to build a cruiser then the extra gear of the 4 speed would probably be a better idea but they are nowhere near as strong.

[SteveHQ]

Would be more a reliable cruiser, but I'm interested in the cost v effort for both options. How much loom adaption is needed for each, what about speedo, neutral switches etc? What about changes like flex plates, Torque converters? I wanna make sure I've got the full picture before wandefing down the path (I often get lost ;-) ) Have you done the conversion?

[duke5700]

T400 means no real loom change at all. It is a mechanical box as far as the ECU is concerned.

Flexplates off the shelf now to make a T400 bolt up. Easy setup, but no over drive.

4L65e means I would sell the manual loom and ECU (though the ECU can be reflashed for $100) and buy and auto one.

[SteveHQ]

T400 means no real loom change at all. It is a mechanical box as far as the ECU is concerned.

Flexplates off the shelf now to make a T400 bolt up. Easy setup, but no over drive.

4L65e means I would sell the manual loom and ECU (though the ECU can be reflashed for $100) and buy and auto one.

Righto, so the TH400 seems to be an easier option, thanks for the info :-)

What about parts that I can transfer from the VZ? I can hang onto stuff like the cats but is anything else worth/able to be re-used like radiator etc?

[duke5700]

All comes down to your fabrication skills as to what you can make fit.. to be honest by the sounds of it you only really want the ECU/Loom and engine.

I would't think anything else would even come close to fitting. I believe Pacemaker do off the shelf extractors etc.

It is going to need things like a fuel pump etc to cater for the EFI related parts, so maybe you can butcher then setup to work in the HQ tank?

[white lie]

Its a common conversion these days so what is needed is available off the shelf. May be easier to sell the parts off and use the cash to buy the parts suited to the conversion rather than modify things to make them fit. As said, depends how handy you are on the tools