Hi all

I need your kind advice on the following:

It started with the need to generate the rumble boxer of subaru's out of my vf 37 set up where i came to know there is no way for that as it is an equal length setup twin scroll.

My tuner here advised me of changing the whole setup of vf 37 with vf 24. power would also increase by 35 HP (roughly) and spooling would be faster with almost minimal cost as he is going to trade in with my old parts. I would also get the exhaust tone i want. However, through my searching over the net, i came to know max it can handle is 17 psi only?!

What i am afraid of is reliability of the engine as if it is already designed for vf 37 then i am almost sure any other set up wont be as reliable.

what other replacements is safe you think? (vf 22 would be the best "power wise" but least reliable)

appreciating your valuable feedback.

Regards,

 

I would not swap to any of the low 20 vf series. I have a VF23 and sourcing replacements, and part for it are almost impossible. Get something that is rebuildable. Look for an 18g, run 17-18psi on it and have fun.

If you're still stuck on the idea of a VF turbo, get a 22 for max power and 34 if you're looking for a tad more mid range.

The car has a twin scroll equal length set up for a reason, you'll lose top end power curve going to unequal length headers just so you know.

 

Why do people keep asking technical questions in the projects forum?

 

Thanks for the feedback Heedz and apologies for the wrong post in the projects forum.

04GG Please advise where else should I address this sort of queries.

 

If your tuner is telling you there is a 35 hp capacity difference between a VF24 and VF37 you need to find a new tuner. There is maybe a 15 hp tops difference between the smallest Impreza IHI turbo and the largest, nevermind these two. Your tuner is also trying to take you. A VF37 setup is worth more than a dated VF24.

 

Yep, your tuner either has no clue or is trying to basically steal your parts by selling you lesser ones.

In your case, might have wanted to ask in the motor forum that more closely fits your car Engine/Power - EJ25T (STI and 2006+ WRX) - i-Club

 

Actually, here: Engine/Power - EJ20T (pre-2006 WRX and JDM) - i-Club

 

Missed the 04. just saw STI/Spec C. Are all Spec Cs from the GD body 2.0L? Did the 2.5s only come to North America or did they stay 2.0L in Japan only while they were still in competition?

 

I believe he's doing so. I kept my VF37 ultimately and happy with it an kept my fingers crossed. I believe spec c's, regardless of whether 2.0 or 2.5, been exclusively produced for Japan and austria.

Noted the forum pointed and next time will post in there. Thanks Gents

 

2.0L. Only the Forester was recently a 2.5L.