Assuming the engine is in excellent condition with good numbers across the board. All OEM internals, how long would a B18b last boosted? With redline set at 6000 and fuel cut at 6200. I was thinking that since the redline and fuel cut would be so low, that it would be a considerable amount of less stress on the rod bolts and other parts of the engine. Would having the redline set at 6000 be a signifigant improvement on the longevity of a boosted LS?

 

Longevity is usually relative to tuning & maintenance.

I have tuned b20 & b18a/b turbo setups that have lasted years without issues making anywhere from 250-300 whp.

A revlimit of 6000 is pointless, the revlimit on a stock b18a/b setup should be approximately 7100 rpms.

 

I understand that the stock limit is 7100 but if the LS's power drops off near 6 why keep revving it to 7? Why not shift and start the power band over..

 

My engine has been running for coming up on it's 3rd year now with no hassles.

Ran a stock Dseries at ~210whp for 2 years, daily driven. Never blew, just swapped it out for a built one.

 

D series FTMFW

 

NA maybe but boosted LS should hold power to 7000 unless your using a tiny turbo, anyhow here are a few reasons to shift at stock redline:

-It's the STOCK redline
-LS tranny already has big enough rpm drop between gears, shifting lower will only worsen that
-starting over your powerband is not good when you are starting from the bottom of it.

Why don't you just leave the OEM redline where it is, drive it yourself and see what it does, if you want to keep it under 6 its your car do as you like.

 

i really see no reason to shift at 6000. i used to have my limiter set at 7400 bone stock motor. just because rev limiter is set at 7400 doesnt mean i always have to shift there, i can still chose to shift wherever i want.


longevity is in tune and how you drive it. i got about 15k boosted miles out of a stock ls making 240 and 205tq. motor had 205k miles when i first boosted it, put it through hell when boosted and it still ran fine and had 165 compression when i pulled it. im still using parts of it on an na build now, years later

 

i have friend that lives in philly with a bone stock b18b making 330 to the tires, the engine/car/setup has been running since 2003

 

Those are good points.
I was just under the impression that 7100, stock redline was nearing the limits of the rod bolts...

I think I'll take your last piece of advice and just see which one feels better.
Its a daily so i'm looking for longevity over peak power.

 

So tune it really conservatively and have fun !

 

Honda does not build motor's close to it's limits.

 

yay honda

 

How about you do what Honda figured people would do - shift when deemed appropriate?

Leave the stock redline, tune it just a little past it, and only get near redline when you want/need to. Unless the automotive world suddenly got turned upside down, you don't shift a daily driver at redline every gearchange. I was just looking at a 400whp LS/Vtec, I think over on the eCtune forum. Bone-stock b16 head & b18b block, decent turbo kit. The motors can take a lot on occation.


Keep the boost & rpm's low until you feel spirited, and it will usually last quite a long time.