Is it as easy as a straight swap? I'm guessing the rear diff ratio is different to the wrx diff, so i'd require the matching diff. Also am i right in thinking that the P1 box uses and electronic speedo, where as the wrx gearbox uses a mechanical speedo cable? If so what is the way around this?

 

the box will fit but u will need the matching diff
not 100% certain but think u just swap where it mounts in to the box?

 

give david at A.P.I and ask for his advice.

 

Whats your reason to fit one?

 

Thanks for the replies guys.
My current gearbox is crunching when down changing into 4th, i guess due to a worn synchro. Being a TY52 box, which are supposedly the weakest, i can't see the point in stripping and rebuilding it. Also the box is very low ratio, 70mph is @3500rpm and 80mph is @4000rpm. As the car is running around 305-330 (depending on which rolling road i go by) i was advised to go for an STI 5/6 box, which is basically what a P1 box is but with the P1 having a slightly longer 5th. I'm not running enough power to require a 6 speed or PPG or the like.

 

P1 gearing will be the same to within a couple of mph, given the 4.444 diffs, dont forget yours doesnt rev to over 8000rpm as per P1 STI

 

Which box would you recommend going for then, a P1 or STI 5/6? Also how much would you say a resonable price is for a recon box or second hand box? Plus the diff as well i should say.
Think i should give David at API a call to discuss some options with him.

 

I run a 2006wrx box with a 4.111 diff, i believe it has the ratios you desire.

Speeds at 7250rpm limiter

WRX STD GEARING TY752VB3FA
36
60
86
114
151

P1 GEARING TY754VBAAA
36
61
89
118
156

MY 06 WRX TY754VG7AA
35
65
95
127
167

 

https://www.scoobynet.com/private-fo...d-gearbox.html

 

Cheers 172.