I am planning a cam swap for this winter and was looking for some input. I was hoping for about 500+rpm than current setup which seems to be done at 5700.

Current set-up is:

XS 274S 108 lsa

237/241 @.050

.496, .501"

406 sbc, Air gap RPM, Sportmans 200cc extensively ported (no flow #s), 9.85:1

Scat 9000 crank and steel 4340 bushed 5.7 rods

TKO 600, 3.73 rear

I am leaning toward the XS282s but a little concerned about loosing a lobe on break in and the durability of Xtreme Solid FT cams, so far so good but I use the oiler lifters and my current grind is too mild..

I would like to run a Hyd roller (X288HR maybe) but can't really afford $600 with the cost of lifters. Max rpm w/o rev kit?

For the sake of interest what comp hyd roller lifters are the best, I recall some being recalled do to needle bearing failures.

What are my options with my current compression ratio?

Thanks in advance, SS.

ahhh another reftrofit hydro roller post... will be watching closely...

Comp lifters are junk, get some cranes or lunatis

Mine and your combo are very similar and am in the same boat as you. The cam makes killer mid range but not a bunch of top end HP. I was considering a cam swap as well. I have a touch more compression than you but not much. I have a new comp 294S in the box that I most likely will use one of these days. Hyd roller sounds nice but shoot by the time your done your looking at right at 1000 bucks.

Spoke w/ Lunati today and they recommended this cam http://www.holley.com/401A4LUN.asp

Of course break is a crap shoot with full spring pressures as with any FT. Tech stated that it is pretty much a voodoo profile.

The description is lack luster but it only matters how it runs; Kind of an expensive experiment!

6D9-straight profile I.e (294s) won't probably work as well with my heads compared to your afr's. you should run it and let us know. I think that Eric68 ran it with good results.

Hyd Roller is out of my price range; I will have to get a spring compressor and air fitting etc..

I will stick with a split profile: Has anybody run the XS282S? I would really like to hear some feedback!
SS

Idoxlo8 is running the XS282S in a 383. I just talked with him awhile back about our combos.
That Lunati cam sounds like a nice one as well as the XS282s. What about slapping some 1.6's on the current cam to help it out a bit. A heck of alot easier and less risky than a cam swap. Also have you played with your jetting much?? Mine used to lay down at about 5300 before I started folling with the jetting in my 3310. Once I stepped up the secondarys....bang pulls hard right to 6K. Granted its not gonna go to 6500 behind a 400+ cube sbc but 6K should not be a problem. Peak HP though is probably right at around 5500 or so though.

I WAS running the comp xr282hr retro roller until I just pulled it, found some slight wear patterns on the up ramp lobes. I found a flake out on one spot so cam is gone but it was a cast roller . Other than that, I lost my fuel pump lobe using the stock and brass tip pushrod with stock fuel pump. Is not a bad set up for what I got. In fact, for replacement, UD Harold is cutting his version of this cam on a billet core with the Everwear dist gear. His cam will be better on the closing side of the ramps. Nothing wrong with the 853 roller llifters. I would not go any bigger than what I have due to vacumn and driveablility issues, in my case , I do long distance fast paced cruising.

Good point, I am just wondering if the cost associated with the RR 1.6/1.5 is worth it? Split set of magnum RRs is $$$380,

full set is cheaper but I am not sure if 1.6 on the exhaust is good idea. I am kind of leary of the stainless steel knock off brands.

According to a tech at Comp they won't make the difference? Stated I needed to increase the swept volume via duration increase which the increased ratio won't yield. I would think that the added lift would help.

Hard to say, it is a definite option that I have been considering.

6D9 did end up changing to the 1.6s, I thought you were considering it at one point?

Just for reference what is your jetting, I presume you put a sec metering block in your 3310. Let me know it should give me an idea.

Thanks for the responses. SS

I did do the 1.6 swap on both sides. I did not test one vs the other but I knew the motor would want a bit more cam and this was bar far the easiest way. I just I did not want to take the risk of having a cam failure. As far as my jetting it was stock 72/76. So I did the block conversion and now I am 74/84. Like I said before it would pull hard to 5300 before and then just hit the wall. Now......pulls like a train to 6000+. You have 1.5 rollers on it right now right?? Comp sells them in a set of 8 for $179.99. Its goes under part# cca-1305-8.
Check them out. What carb are you running and what jetting??

4780-2 800cfm Dbl pmpr
(stock is 70-85) jetting is 75-86 which is what I used at the open track event recently. Choke horn has been removed and smooth bored etc. I am sure it flows more than enough air.

I have some 87s that I will probably put in the secondaries and go back to 74 in pri for the street.

I really noticed it lay down in 4th in upper rpms. This was by far the hardest I have driven the car and not something you could easily tell on the street. However, I have noticed with smaller primary jets it does go flat sooner. It also has a 108 lsa, from what I understand they peak harder and then fall off quickly.

The RRs I have are aluminum cam dynamics-(crane energizer) 1.5s, not sure I would want to mix them with the comp 1.6s.

I have been kind of worried about them and should replace them before it is too late!

I guess I need to make sure I have the pushrod clearance in the head holes before doing the swap.


Are you lashing at .16 int .16exh?

SS

Yes on the lash. .16 on both sides.

To heck w/ all the BS and either install a good old CC 282S for max grunt or their 294S for more topend and not worry about the cam!

And just use 1.5 ratio rockers!!

Nothing fancy at all here, imho!!

Sucker should pull HARD w/ either one!!

pdq67

Pdq...I dont think the old school 282s is gonna give anymore topend performance than the XS274s. Plus the 274s will work better with his comp ratio.

I agree the 282S is a great mid range cam, but won't give you that much on the top end. It looks very comparable to the one you already have. I like my 282S, but I want something more. A cam change is not in the picutre for quite awhile.

Guys,

And right, the XS274S should do good at 9.75, but that said, I figure the 406 due to it's size will help the 282S and 294S cams.. And both their lobes should be a bit easier on the valvetrain, imho!!

That's all, nothing fancy..

pdq67