Another Cam Question

Gone · #1 22nd July 2006

I have an '06 XL-883 that will be getting the NRHS 1212 conversion and their new special headwork that allows use of flattop pistons this winter. What is the difference between the stock 883 cams and the stock 1200 "W" cams? Would there be any advantage to replacing the 883 cams with the "W" cams? Thanks.

NRHS Sales · #2 22nd July 2006

Calbo,
That kit is designed to use SE 536 cams as they have a very long duration that helps bleed off compression. You do not want to use flat tops with 883 heads and either of those stock cam. We have a special reverse dome piston designed for that. So unless you are getting the 536 cams do not use the flat tops.

aswracing · #3 22nd July 2006

Less than a dime's worth. You don't want either of those grinds with that flat top conversion package.

One of the things that makes that flat top conversion work so well is that the chamber relief work didn't touch the squish band. We still have the full squish band around the perimeter of the chamber.

But this necessarily leaves the CR a bit higher, because you're not touching the area that gives the greatest opportunity for adding chamber volume. We decided to put the 536's in rather than reduce the squish area, because the later intake close event of the 536's bleeds off some of the compression, and therefore makes the higher CR manageable and pump gas friendly.

Do that combo with "D" or "W" cams and you may create a pinger.

aswracing · #4 22nd July 2006

We cross posted, but we said the same thing

Gone · #5 22nd July 2006

Quote:

Originally Posted by NRHS Sales

Calbo,
That kit is designed to use SE 536 cams as they have a very long duration that helps bleed off compression. You do not want to use flat tops with 883 heads and either of those stock cam. We have a special reverse dome piston designed for that. So unless you are getting the 536 cams do not use the flat tops.

Thanks Dan, I tried to call yesterday but I guess I was either too late or y'all were too busy. Would there be any advantage to using the "W" cams with the reverse dome piston kit?

aswracing · #6 22nd July 2006

You're talking about an awfully mild build, "W" cams with 10:1 under 883 heads with those small valves. The "W" cams are very narrow and close the intake early. More squeeze + more cam = more power. 10.5:1 with .536's works very well and is no harder to do.

Gone · #7 22nd July 2006

Quote:

Originally Posted by aswracing

You're talking about an awfully mild build, "W" cams with 10:1 under 883 heads with those small valves. The "W" cams are very narrow and close the intake early. More squeeze + more cam = more power. 10.5:1 with .536's works very well and is no harder to do.

Thanks, I appreciate the info - I was just trying to figure the best way to get the most bang-for-the-buck as I could get the "W" cams really cheap! Oh well, damn the bad luck LOL!

I'm curious what the difference in hp/trq was in the dyno test for the rvs dome 1212 kit vs the 1212 flattops with new special grind (Mile Campbell grind)?

NRHS Sales · #8 22nd July 2006

We never did a test between the 2. Sorry.

Gone · #9 22nd July 2006

Quote:

Originally Posted by NRHS Sales

We never did a test between the 2. Sorry.

Bummer! LOL!!! There's abt a doubling of price between the two so for me to justify the additional expense the performance difference would have to be pretty substantial! Care to "ballpark" it?

sporty58 · #10 23rd July 2006

I am not going to stick a number to it but going from a 10:1 is setup with stock cams to a 10.5:1 setup with .536 cams is going to be some of the cheapest horsepower you can ever buy.