Re-cored (bigger) CT12As vs a big single

[Ribfeast]

*double post*

[JZA70 R]

What do you guys find heatsoak like on the big singles vs the twins?
I find the twins heatsoak very badly, I only get 1 or 2 runs in before I have to let it cool down a lot. Losses are 20kW or more.

Have the exact same problem. I always thought it was the factory ecu sucking the power BECAUSE of the heat. but its not. its the heat sapping the power.

[Dieseltrain]

Hmm, My latest dyno sheet i have the power figure from, was the 21st full power run in 80 minutes... Might chuck her back on whilst its nice and cold and not heat soaked and find this " 20" or so

Thanks for clarifying that Linden Nothing wrong with 240rwkw EITHER just quietly managed 11.8 for me so far!

SHould be a Nice early riser and have a great mid range too

[Ribfeast]

I'd say it is either the turbos getting hot, and making their output hot, or it is the intake manifold/plenum getting hot. There is an air temp sensor in it I think, so it probably affects things in a negative way as intake temps increase.
A phenolic gasket/spacer might help with this somewhat...don't do them for 1JZ though AFAIK, just 2JZ Stops heat transferring from the head to the intake manifold.

http://www.gizzmoelectronics.com/product_gasket.htm

[Dieseltrain]

Yeah, Used to run one of those style spacers on my old mans Built 347 stroked EFI windsor. You could feel the difference.

[Ribfeast]

Wonder how they go holding boost etc...

If someone makes a 1JZ version I'll be keen

[JZA70 R]

yeah same im down for one... so the 2j head is different in that regards?

[big wad]

that so called little turbo makes shitloads more power at all rev ranges , the response is amazing and if i can ever sort that top end breakdown out i will be a very happy man .it pulls harder to 6000 rpm than the twins and just as it really starts to get into its stride pop pop bang ,time to change gears. the new coil connector plugs made it a bit better so i,ll keep searching for the prob. cheers bigwad

[The Real Roadrunner]

Hi Linden,

I don't think I have seen that one in newy, plates ring a bell though...do you know him?

Cheers,
Braden

built the car ages ago and the customer sold it to a guy up that way.
just wondering if youd seen it around.

big wad, i thought it would have better spool than the twins just wasnt sure. and for what your doing i dare say it would be the best thing for the job.

cheers
linden

[pete05]

I think IMA01J is owned by eviljacks brother in sydney

[chris davey]

yeah same im down for one... so the 2j head is different in that regards?

yes it is. Exhaust and inlet ports are different.

[Dieseltrain]

1JZ head made by Yamaha, 2JZ head by toyota i thought?

[Norbie]

Both are Yamaha designs, as are practically all performance-oriented Toyota heads since the late 60's.