Austarion

Hi guys.

Just wondering what the best performance mod's for a JAP spec 4G54B 2.6litre Starion engine is? Also, does anyone have some information on the JAP spec or is it like the UK one?

Woody

The best mod to do would be to get rid of the throttle body setup and replace it with Magna multipoint EFI. Other options would be to remove the balance shafts and have the engine balanced, cams, and all the usual stuff like exhaust, more boost and so on.

All comes down to how much you want to spend.
Basic mods are as per aussie 2L starions (boost, exhaust, etc)
$$ mods are as above post with attention to the jet valve head?, exhaust manifold etc. Replace with tried and tested Magna/Sigma turbo bits & aftermarket computer.

I thought the UK only got the 2L ??

I'd reckon jap spec would be similar to US spec though.

Have a look at this thread and see what Steve has done to his engine in his US-spec Conquest: http://austarion.com/forums/viewtopic.php?t=283

I have a spare's car which works perfectly laying on the grass, It is a Magna and it has the multipoint injectors. But I'm not sure if I shoudl change the EFI because I would then have to do the computer and then change one of the intercooler piping.

Woody

The UK got the widebody 2.0 and 2.6 (in the last year). They did not get the 188HP 2.6 like in the US. The difference between the HP of the widebody cars in the US was mainly the boost (7.5 - 10.5 psi) through the years.

Fair enough, Widebodywoody. Have you been to the US forums? Plenty of info there: http://www.starquestclub.com

Yeah, I have tried the US forums. I got some good ideas from there. Does anyone know for certain if the MAF sensor on the 4g63 is the exact same as the one on the 4g54? I want to do the airbox mod but I want to keep my original box for future purposes. If it is the same I can use some of my spares.

Woody

With power levels up to around 180rwhp (maybe more have not tested) at the wheels the standard airbox is no resrtiction. The restriction is the airflow meter and the plastic intake thing under the front wheelarch. I unclipped my lid and left it sitting open (no airflow meter and plastic intake removed) during a dyno run and it made absolutely no difference. Maybe for 200rwhp+ it may be a problem. But if your car is pretty standard it will make no difference at all.
It's easy to try. Put the car on the dyno and do a run with the lid on and a run with the lid sitting free. WidebodyWoody (I think your the guy with the widebody 2.6!) you can do that because your airflow meter is mounted in the lid so the factory ECU will still work. You can't do that with the Aussie cars because the airflow meter is mounted to the bottom of the aircleaner and when you lift the lid the airflow meter is then unconnected and obviously can't measure any air flow.
By the way do you have any dyno numbers and what boost is your car running?

cheers

I know that it doesn't effect it much. I just wanted to know if the MAF sensor ask's for more air for the bigger engine etc.

Woody