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View Full Version : Conversion w/ N4's is noisy


Mattbastard
15th June 2008, 21:22
Now I've heard the SE bolt in cams are a bit more clattery, but this sounds like piston valve contact here. What I have is .020" over Wiseco 10:1 conversion pistons, SE .497" cams, stock 883 heads with an NRHS competition valve job, and a 1200 ignition module. As soon as I fired her up I got some clatter, which could be mistaken for piston/valve contact. When I put it together after I waited for the lifters to bleed down I spun the motor and had no contact. Also, when I did a conversion before with the same stuff I used JE pistons and there was plenty of clearance, so I didn't check this time.

My question is: has any of the forum heard of my combo having problems with valves hitting the piston? I used stock HD gaskets in case this matters. I know they're thicker than the Cometic gaskets.

Thanks

Mattbastard
15th June 2008, 21:53
False alarm folks, nothing to see here!!

It was pinging. I had the timing too far advanced for the new CR. I just backed the plate off a bit and fired it back up and the "knocking" is gone.

Boy them cams is rattly though.

rottenralph
15th June 2008, 22:29
I switched from n8'2 to SE536 this year and I was quite surprised at how quiet the higher lift cams are. I suspect the ramp design has something to do with it. I can do without the clackity clack of hed noise.

Mattbastard
15th June 2008, 22:38
You still on the fence about selling me those N8's?

rottenralph
15th June 2008, 22:41
They are long gone, I think you are talking about the SE536. I won't convert to turbo till fall. I am not sure how that is gonna go so most likely they will go in a box for a while till I am sure the motor is not going to grenade or warse, not start.

Mattbastard
15th June 2008, 23:43
If I were you I'd go back to stock cams with a turbo. Forced induction loves no overlap cams.

rottenralph
16th June 2008, 00:06
That is the plan. I just happen to have my original cams on the table.

Mattbastard
16th June 2008, 00:37
Soooo........

whatcha doin' with the 536's? ;)

ReddTigger
16th June 2008, 00:46
Soooo........

whatcha doin' with the 536's? ;)

I think he has a waiting list for them already :)

rottenralph
16th June 2008, 00:49
They will be waiting in a box till I know the turbo is on for good. That may be never. In the same box will be my dyna 2Ki, supertrapp, S&S super E, and more.