Xtnct00WS6

iTrader: (8)

I ordered a 230/234 .612 .598 111 +2

...I got a 231.6/235.8 .616 .601 112.3 I'm not sure what the advance was.

What gives?! From 111 to 112.3, that seems a bit too far off to me! That changes my DCR and my overlap! I REALLY want to send it back! Thoughts?

This looks like a trend based off this thread.

ArcticZ28

iTrader: (14)

Well, it's never going to be dead on, but that looks a bit out of spec if you ordered it on a 111. Have you called them up and told them about it yet? That would be my first move.

SSNISTR

iTrader: (10)

Yeah that is too off.

speed_demon24

iTrader: (6)

That's nothing to worry about, and if you aren't going to degree it when you put it in then I wouldn't even think twice about it.

Ryan02SS

iTrader: (3)

I agree. If you don't degree the cam in you don't know the valve events anyway so the point is pretty moot. If you are going to degree the cam in at the desired ICL and confirm valve events then call Comp. Comp will take care of you. A tech named Eric has always been very helpful to me.

Xtnct00WS6

iTrader: (8)

Well it changes the overlap from 10 to 8 and lowers the DCR. I was going to degree the cam btw.

How do I figure out the advance based on this?

speed_demon24

iTrader: (6)

LSA - ICL so you have about 2 degrees of advance. If its really bothering you call comp and see what they say they might be able to grind you a new cam thats closser to the specs you want.

voda1

iTrader: (4)

2 degrees advanced = 112.3LSA - 110.3ICL

thehammer69

iTrader: (2)

You cam is only 1.3 degrees off. Going on what Comp told me from my bad grind fiasco, anything under 2 degrees is in tolerance. In my case, Some of my lobes were beyond two degees off on the advance so they reground it for me.

Hammer

Xtnct00WS6

iTrader: (8)

So if I asked for a 110 LSA and they gave me a 111.9, it's within their tolerance? I could understand that when it comes to duration, but not LSA. I don't remember seeing that much change in LSA from other people's results. Thanks for the help everyone.

I'm sending it back to Thunder by the way. They're going to double check the specs for me. They've always treated me pretty well so it looks like it'll get taken care of.

thehammer69

iTrader: (2)

Yes, a 111.9 LSA when ordering a 110 is within their allowed tolerance of plus or minus 2 degrees.

Hammer

Tom@SpeedInc

iTrader: (5)

I'm sure if more people had their cam doctored they would have similar findings, from comp, cam motion, lunati, etc.

SSwanner

iTrader: (128)

yes sir, very true!

mine is a 248/254 on a 110 LSA...

actually its a 248.2/253.7 on a 110.9 LSA which is fairly close but not EXACT

BTW +/- 2 degrees is not gonna make or break you in a street car/motor now if its a custom high dollar race motor that COULD be a slightly different story.

Ryan02SS

iTrader: (3)

I agree. BTW my TR224 is a 223.7/224.2 .561/.563 112LSA

nmp27

iTrader: (2)

Same here, mine was about 1.5 off, but what can you do, chain stretch can easily make that up.. OR make it worse

Xtnct00WS6

iTrader: (8)

Well I put the new specs into the VE calculator and it seems like my overlap is not changed. The extra duration makes up for the wider LSA to keep the valve events similiar. It still lowers my DCR a decent amount.

Xtnct00WS6

iTrader: (8)

Was the LSA off by 1.5, or was it the duration?

Thanks