Yeah, seems to be the compression. I was extremely happy with my set up, 3k with a K head, twin 2-1 extractors with true dual exhaust and big quiet mufflers. Never had it tested but it was a Honda killer for many many years. I would race anything on the street and surprised quite a few folks...the 351ci Ranchero guy was real sad...so were many 5.0 mustangs....It could smoke 1st and 2nd, burn 3rd real good and chirp 4th any time I wanted. I have twisted the rear axle out of it a few times, breaking the bolts in the leaves, I'm surprised the tiny little u-joints didn't go first. I made a 101 mile trip at an average speed of 124mph....and got clocked once at 131mph (it took a while to get there). Unfortunately after about 10 or 12 years of constant hard driving, it ended up cracking all to pieces and now I have just a stock 3k back to original everything. I know I keep telling this story but, man, I really loved that motor....and it went to 6600rpm all the time. I never really even gave it a break-in period....Got it together, started it up, smoked the tires out of the shop, and proceeded to go out and piss off Honda drivers. I especially liked the ones with all the nifty lookin gear, lowered with the big obnoxious mufflers sticking out the back, that have probably spent thousands of dollars on wheels and engines only to be beat by a 40 year old nearly stock $300 Corolla. I could never beat a stock early Civic though, I don't know what year but the real small ones, some of the first...they could keep up with my old Kawasaki on the freeway.

Edited June 24, 201313 yr by CorollaNut68

4K ALL DAY!!!!

my 4k has 60thou oversize flat top pistons,decked block, 3k-b shaved and ported head,heavy duty valve springs lumpy cam etc. The cam makes a big difference but the compression is quite high so the stock starter motor struggles a bit

On 6/23/2013 at 8:24 PM, coln72 said:

Cam specs were different to.

How about the valve spring, are they same?