Cam timing effects on compression
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Re: Cam timing effects on compression
If 61 degrees should give a cranking compression of 215, and knowing that increasing the closing degree lowers the compression, I assumed that maybe you are advanced one tooth (or 9 degrees). I was hoping that 70 degrees would drop it to 160psi and that would prove to be your problem.... Oh well.
What about retarding the cam a tooth and trying it? Cheap and easy to do. If it improves, maybe try another tooth until power drops off. Then fine tune it closer by advancing/retarding one 4 degree hole on the sprocket. Each hole is almost 1/2 a sprocket tooth.
You expect 160hp? So you are down about 50%... nothing to loose by trying.
What about retarding the cam a tooth and trying it? Cheap and easy to do. If it improves, maybe try another tooth until power drops off. Then fine tune it closer by advancing/retarding one 4 degree hole on the sprocket. Each hole is almost 1/2 a sprocket tooth.
You expect 160hp? So you are down about 50%... nothing to loose by trying.
Last edited by datzenmike on 08 Feb 2009 20:01, edited 1 time in total.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
Re: Cam timing effects on compression
Well....all back to good. The timing mark plate was knocked and what I assumed was TDC was not, straightened that out, then changed the cam timing. Now 215 compression on all cylinders.
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Re: Cam timing effects on compression
Woot!
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
Re: Cam timing effects on compression
glad to hear you got it sorted out. can't wait to hear new dyno numbers.
Re: Cam timing effects on compression
Good to hear it was something simple. It would be good to see and hear some footage of it at full song next time its on the Dyno or at a race track.
Peter
Peter
Some Boost in my FJ is good....More is better!!!
Re: Cam timing effects on compression
Glad to hear you had an easy fix. I love those - especially when you can find them (and haven't already spent a bunch of effort chasing down the wrong stuff.)
Finished is better than perfect......
Re: Cam timing effects on compression
I did really, but it was multi faceted problem as it turned out. My distributor needed to be recurved for the new motor too, which added to the confusion.James wrote: (and haven't already spent a bunch of effort chasing down the wrong stuff.)
Re: Cam timing effects on compression
So when are you going to re Dyno your car so we can really know what that L16 puts down?
"People don't like it when shit doesn't match their rule of thumb." Sam
Re: Cam timing effects on compression
That is impressive to make that call over the internet. You are the "L" master zen.datzenmike wrote:If 61 degrees should give a cranking compression of 215, and knowing that increasing the closing degree lowers the compression, I assumed that maybe you are advanced one tooth (or 9 degrees). I was hoping that 70 degrees would drop it to 160psi and that would prove to be your problem.... Oh well.
What about retarding the cam a tooth and trying it? Cheap and easy to do. If it improves, maybe try another tooth until power drops off. Then fine tune it closer by retarding one 4 degree hole on the sprocket. Each hole is almost 1/2 a sprocket tooth.
You expect 160hp? So you are down about 50%... nothing to loose by trying.
Denis Gagné
AKA VGwagon
69 510 VG30e swapped
73 240z VG30et swapped
86 300zx na2t VG30et converted
AKA VGwagon
69 510 VG30e swapped
73 240z VG30et swapped
86 300zx na2t VG30et converted
Re: Cam timing effects on compression
This week...if my "ship comes in". I blew $190 last week on figuring the problem.icehouse wrote:So when are you going to re Dyno your car so we can really know what that L16 puts down?
Re: Cam timing effects on compression
time for predictions...
I say 165HP
I say 165HP
Re: Cam timing effects on compression
510rob wrote:time for predictions...
I say 165HP
I'm guessing 148 WHP
"People don't like it when shit doesn't match their rule of thumb." Sam
Re: Cam timing effects on compression
Alright, I should be more specific. 165BHP, at the 'brake', on an engine dyno, calibrated to S.T.P. conditions, operated by a credible and knowledgeable person, all overseen by at least three dependable and reliable witnesses, with one witness tasked with fair and frequent distribution of ice cold beers...icehouse wrote:510rob wrote:time for predictions...
I say 165HP
I'm guessing 148 WHP
Re: Cam timing effects on compression
510rob wrote:Alright, I should be more specific. 165BHP, at the 'brake', on an engine dyno, calibrated to S.T.P. conditions, operated by a credible and knowledgeable person, all overseen by at least three dependable and reliable witnesses, with one witness tasked with fair and frequent distribution of ice cold beers...icehouse wrote:510rob wrote:time for predictions...
I say 165HP
I'm guessing 148 WHP
I thought you were going to say it had to be on a Rebello dyno haha
"People don't like it when shit doesn't match their rule of thumb." Sam
- bertvorgon
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Re: Cam timing effects on compression
I'm going to say 145.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer