increase rev limit of rb25det series 2 - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

finallymysti · 12-15-2016, 10:48 AM

so, i want to increase the rev limit of my series 2 rb25det. whats needed to do this ? i'm not looking to make crazy power, so i don't need to build the block, but on the head side of things whats needed? thanks

jr_ss · 12-17-2016, 09:13 PM

Springs at the very least. However, there's no need to increase the revs if you're not making power up there. You'll prematurely wear the engine.

Reasons to increase rev range; you've swapped in a larger turbo and/or upgraded cams/valvetrain.

Reasons not to; oiling issues, rev higher without making power.

BigKriss · 12-18-2016, 12:46 AM

My std RB25 went to 8000rpm no probs, did have the head oil drainback problem though. Head drain mod and all was good. Motor lived for over 5 years..

12-15-2016, 10:48 AM	#1
finallymysti Join Date: Oct 2015 Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	increase rev limit of rb25det series 2 so, i want to increase the rev limit of my series 2 rb25det. whats needed to do this ? i'm not looking to make crazy power, so i don't need to build the block, but on the head side of things whats needed? thanks

12-17-2016, 09:13 PM	#2
jr_ss Post Whore! Join Date: Dec 2005 Location: Pa Posts: 6,410 Trader Rating: (35) Feedback Score: 35 reviews	Springs at the very least. However, there's no need to increase the revs if you're not making power up there. You'll prematurely wear the engine. Reasons to increase rev range; you've swapped in a larger turbo and/or upgraded cams/valvetrain. Reasons not to; oiling issues, rev higher without making power. __________________ My SR20VET Does your VTC gear rattle in your S14/15 SR? PM me.

12-18-2016, 12:46 AM	#3
BigKriss Leaky Injector Join Date: Dec 2012 Location: South Africa Posts: 141 Trader Rating: (0) Feedback Score: 0 reviews	My std RB25 went to 8000rpm no probs, did have the head oil drainback problem though. Head drain mod and all was good. Motor lived for over 5 years..