Redline question about GSR/LS hybrid...

[Ispankyourmom]

Cars: JDM 97-01 Integra

Mileage: 30,000-35,000 miles

1834cc (DOHC)

Horsepower: 142hp@6300rpm

Torque: 127lbs-ft@5200rpm

Compression: 9.2:1

Bore: 81mm

Stroke: 89mm

OBD: 2

Redline: 6800rpm

Those are the specs on a JDM LS block from totaljdm.com - the redline is at 6800 RPM - not exactly great - I'm sure it's much higher for a non hybrid GSR block/head engine - so my question is - is the redline on an LS/GSR hybrid (LS block with GSR head) going to be (?) like 9000 RPMs? or should I let off the gas or shift up a little over 7,000 RPMs?

[S13wanabe]

They usually make peak power in stock LS/Vtec formation at about 7,800 rpm. I shift mine at about 8,000-8,200. I have pr3 pistons in mine and I still only rev to about 8,200. I have taken it to about 8,500 though.

[whtteg]

With a block girdle installed 8k is as high as I would go and without a block girdle 7500 is as high as I would go. After 8k you will be getting some rather bad vibrations from the increased piston sideload. If you want to be able to have a high redline then get the complete B18C1 motor.

[S13wanabe]

I just have a stock bottom end with pr3 pistons and I rev up to 8,200 all the time with no problems. My motor has over 60,000 miles on it now, with no problems, and like I said before, the peak power on an LS/Vtec is at about 7,800rpm. I'm not an expert, but I haven't had any problems with my LS/Vtec.

[whtteg]

Originally Posted by S13wanabe

I just have a stock bottom end with pr3 pistons and I rev up to 8,200 all the time with no problems. My motor has over 60,000 miles on it now, with no problems, and like I said before, the peak power on an LS/Vtec is at about 7,800rpm. I'm not an expert, but I haven't had any problems with my LS/Vtec.

Are you saying that you have 60Kmiles on the LS/VTEC setup or 60K miles on the block?
You will be alright for a while but long term reliability is going to be cut down if you rev it past 8K too often, the 1.54 r/s is just too low and will have bad piston sideload. Why do you think Honda dropped the stroke for the GSR to 87.2 rather than making it 89mm like the LS? Answer R/S they increased the R/S from 1.54 to 1.58 and this let them "safely" increase the redline and put more agressive proflie cams in.
Bottom line is I like to build motors that are going to be around for a long time without having to worry about how or when something bad like a crakced cylinder wall, or scored up cylinder wall from piston sideload is going to happen. Rather I can have confidence in the motor.

[S13wanabe]

There is 60,000 miles on the LS/Vtec, but would it make any difference that I have the pr3 pistons in it. I deffinatly don't want to screw up my motor, but I do plan on rebuilding it fairly soon. It used to be my daily driver, but now it's my race car, so it isn't driven very often. When it is driven it's always in vtec, and 8,000 to 8,200 is reached all the time. I know how to work on the motors, but I was kinda suckered into the LS/Vtec.