GSR dyno need help

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gtdrummerdude

New Member
Hi all, i'm new to the forum and new to Hondas. I'll just jump right in with my problem and I will post the dyno graph as a reply. I have a JDM B18C short block with a P72-2 cylinder head from 1995. It burns oil at high rpm, i'm sure the oil rings are worn out. Compression came it at 250, 245, 195, 235 on a warm engine. Cylinder 3 is a bit low but nothing that should affect hp much. Mods are Skunk2 or Blox im (Type R copy), DC 4-2-1 header, 2.25" exhaust no cat, Thrush muffler and a no-name air intake pipe with a K&N cone filter. If i'm not mistaken I should be dynoing 160+ hp to the tires. My numbers are low but what concerns me is the lack of power increase between 6k and 8k rpm (only 15 hp), the drooping torque curve after 6k rpm and the sudden nose dive in both curves at 7800 rpm. I was FULL THROTTLE until the lines on the dyno sheet stop. That drop in power at 7800 rpm was under full throttle. The dyno graphs I see even from stock GSR engines extend on to 8500 rpm, curving downward gently but not tanking like mine. My power at 6k is where it should be but after that the engine doesn't pick up power like it should. The suggestions I have received so far: I might have B16 cams in my head, might have incorrect cam timing. Notice how the air fuel ratio gets richer and richer as rpm increases, as if the engine can't breathe so it gets choked up with fuel. I could really use some help with this. Does not look like valve float and doesn't sound like it either, but right after 8k you can feel the engine quit pulling. Thanks in advance!
 

gtdrummerdude

New Member
gsrdyno_zpscbd322c7.jpg
 

newb

phresh
VIP
I believe you need to be within 10% in all cylinders. Having one over 17% lower then the next lowest compression, and 22% lower then the highest might be what your seeing.
 

Briansol

Admins
Admin
VIP
yeah, #3 is in trouble worse than you think.

also check the pcv valve... it may be sucking in your oil problem.
 

Taco15

I wear stretchy pants
if you're sure it's sucking oil you may want to see about filtering that pcv sytstem.

if i'm not mistaken, enough oil vapors or or oil itself can lower octane levels and of course reduce power.
 
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