Tin Indian

Please help me here a little....

I just want a "small" 218/218 114 LSA cam in my 98 TA (A4, 3.23, old Yank 2,800, stage 1 heads & LTs with cats)

CompCams grind #3752 will get me this 218/218 cam with a .527 lift (int & exh).

I see that many folks here are now opting for cams in the .550-.560" + lift. In fact, I believe MMS and others also sell there 218/218 in these higher lifts.
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My question is: Is there [really] a big gain in HP/torque going from a lower lift .527 to a .560+ lift cam (with the same duration and LSA)?
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I just worry about valve train wear/noise with these high lift/fast ramp cams.

This car is an everyday go to work car.....

Thanks,
Ron (stll in Korea)
<img src="images/icons/confused.gif" border="0">

Tin Indian

I realize that the 2002 LS6 engine has a cam in the .550+ lift, but remember, it also has very light valves. Hey, the stock 98 LS1 cam only had a .498" lift. (not that that really matters in this case)

I am not attempting to convince anyone here that the lower lift cams are better for a daily driver. I just would like to hear from folks that may have first hand experience or knowledge with various cam configurations for the LS1.

Again,
Thanks for any input....

[ January 22, 2002: Message edited by: Kimchee and Rice ]</p>

AzzHauler

iTrader: (3)

Good question. <img src="gr_stretch.gif" border="0">

GeorgeC

[quote]Originally posted by Kimchee and Rice:
<strong>Please help me here a little....

My question is: Is there [really] a big gain in HP/torque going from a lower lift .527 to a .560+ lift cam (with the same duration and LSA)?
</strong><hr></blockquote>

It depends on what kind of flow numbers the cylinder heads make... The peak flow numbers on my heads are @ .605 valve lift. That's why I was never really happy with my .532 lift cam. I changed to a .590 lift cam (still less lift than where peak flow occurs), and saw some pretty decent gains (.15 sec or so on average), but the bottom end didn't hold together long enough to do any really serious testing.

IMHO, if you're heads are peaking @ around .550 lift or so, you'd be wasting your time (and valvetrain components) with a .610" lift cam, for instance.

Matt98SS

my guess on stage 1 heads the .527 lift or the comp cams with the .537 lift (IRS sells them) would be fine. George is on the money with the flow vs lift idea.

just look at what some more max effort cars have run NA with the stock cam 11.4X thats faster than some heads/cam cars so lift isnt gonna be king always, its all about combo

RPM WS6

iTrader: (3)

There are a lot of guys around here running T1/B1/C1(.558/.566 lift) type cams in daily drivers for 10s of thousands of miles without issue (as long as good valve springs like doubles or 26918 singles are used). I don’t think anything in the .55X to low .56X range should be considered unacceptable for even daily drivers.

Plus, even stock heads flow pretty damn good, and I don't think cams in the .55X range are overkill for stock heads at all.

[ January 22, 2002: Message edited by: RPM WS6 ]</p>

Matt98SS

I don't think its overkill with the lift part, but more lift = less longevity and more wear regardless.

I think a cam thats 221/221 with .500"/.500" compared to the 221/221/ 558"/558" in a stock headed application is gonna be max around 4 RWHP max difference. now in a ported head application the results will be different

SSBoy

Does anyone know what are Stock Heads Flow?

Ragtop 99

iTrader: (7)

It is not only the absolute value of the lift, it is also the shape of the lope that changes with the fast ramp .56x cams. The valve is open at midlift for longer duration. Besides adding a few HP, it seems to help with part throttle drivability and idle.

Pro Stock John

iTrader: (34)

If I was doing a cam and keeping stock heads I would just go like 530 lift or something like that...

Now with ported heads, I'd look at the max flow, and look at where say 90-95% of the max is.

So if you stuff really only picks up like 5 cfm from 550 to 590... I'd stay 550-560.

WhiteDiamond

Kimchee and Rice,

I orginally had CNC heads and the 218/218 CompCam you mention in my 98 WS6. When you get back to Arizona(if you all ready haven't) my dyno numbers for that set up are at ProDyno. I believe the final number for that set up ended up being 382rwhp and 368rwtq. I used the MAC headers, the MAC Y-pipe with cats(not good cats, so probably hurt my numbers a little), and out a Borla system. This set up ran extremely nice and passed the local IM240 emissions test real nice.

THEN, Nineball(Tony) and Red Firehawk(Brooke) started posting 400+ rwhp numbers for MTI set ups. I scheduled the swap with MTI and removed my CNC heads and sent them to MTI for the Stage II porting and valves. I also got the B1 cam for the car and swapped it over. With no other changes, other than heads and the cam, the new MTI setup pulled 417rwhp. I made some serious changes to the headers(3" collector mod), Y-pipe(Chris at ProD made it full 3" pipe with 3" in/out CarSound cats) and I installed the newer intake, eliminated the EGR, and it made 432rwhp and 397rwtq. The car passed the IM240 emissions in this form also.

The only problem with my numbers for you is the heads where dramatically changed when I did the cam swap. I would actually venture to say the heads alone(CNC to MTI Stage II) would have gotten that CompCam 218/218 set up into the low 400rwhp range and 380rwtq range.

As for valvetrain noise, once you get new valve springs on the car(even lighter duty ones for the CompCam), you are going to get increased valvetrain noise. Even with my MTI heads, the noise was not distracting and barely noticable outside the car with the hood down.

Todd

Tin Indian

Thanks for all the good info

Todd..... I am still over here in the "Land of the Not Quite Right" (Korea)

As far as heads, I am thinking about a set of Joe Prince Stage 1s with the 918 springs. The CompCams 218/218 .527/.527 114 LSA, Hooker or FLP long tubes with cats, an LS6 intake and Ed Wright tuning.

Retain the 3.23 gears and the older style Yank 2,800 stall converter.

Do you think this might make 385-390 rwhp on the rollers?

I don't know what Joe Prince gets from his Stage 1 heads at .525 vs 5.75 lift, but I was just thinking that the CompCams .527 lift may be enough with 218/218 duration.

I don't want to go "overboard" with this car.

Ron,

Pro Stock John

iTrader: (34)

Ron that sounds like a good combo.

WhiteDiamond

Ron,

If you are truely after the upper 300rwhp range, 390 to 395, with an A4 tranny, I think you will probably need to invest in a set of Stage II heads from somebody. I tuned that set up of mine as far as I could get it. I had the light weight aluminum flywheel in there, the ACPT driveshaft, and then I drove the car to Steve Cole's shop in California and he tuned it over 4 days. It was the best I think that cam could do without more flow in the heads. Even if I took an newer style intake to that set up, I don't think I would have gotten much more than 7 to 10rwhp. That would have put a 6 speed car at 390rwhp, it will be tuff with an A4.

You could also consider a cam with the same durations, but faster ramps. The LS1 heads(I have flow sheets around here for both the CNC porting and the MTI porting of my heads) flow so well at lifts below .550", that getting the valve open faster may allow that few extra horsepower to come out and play.

PS....Tom Byrne and another LS1 owner from up north ran the CompCam and similar head(CNC) combo on their LS1 Camaro's. I think Tom B hit 383rwhp and the guy up north hit ~381rwhp. I can't remember his name right now, but he went to a ARE 360 with the twin turbo set up on it. Both of those where 6 speed cars as well.

Todd

Ragtop 99

iTrader: (7)

[quote]Originally posted by Kimchee and Rice:
<strong>
I don't know what Joe Prince gets from his Stage 1 heads at .525 vs 5.75 lift, but I was just thinking that the CompCams .527 lift may be enough with 218/218 duration.
</strong><hr></blockquote>

The JPR Stage 1-x heads that I have were matched well to a .560 lift cam as the heads were close to peak flow at .550 lift.

Tin Indian

Thanks Ragtop....

Well, there may be a little HP on the table with the JPR Stage 1 heads if I go with a little more lift than the .527

Thanks,
Ron

Joe Prince

Hey Ron,
The numbers quoted above are pretty accurate in respect to the 218 527 cam deal. I have new LS1 S2's that I would like you to try, I will give them to you at a great price for you to test and have fun with when you get back! <img src="gr_stretch.gif" border="0"> I know I started on the LS1 motors a little late in the game, but I play catch up real quick. Check my post in the engine section under "New 2.02 valve flow numbers" and you might like what you see.


<img src="graemlins/camaro.gif" border="0" alt="[Chevrolet]" />

RPM WS6

iTrader: (3)

All this has me a little confused. Everyone here seems to feel that some of these higher lift cams (.55X, .56X) aren’t really giving you anything past what a .52X or .53X would on stock heads. If this is the case, why does it seem that B1/T1/C1 cams seem to be trapping higher than the comparable lower lift cams? It just seems that the people running the better numbers here are using cams in the .55X range and up (stock heads or not). Not to say that the smaller cams aren’t doing good too, but I don’t see anything stellar coming from the lower lift guys stock heads or not. If these higher lift cams aren’t doing us any good, then why do we keep using them? There are so many guys with stock heads and B1/T1/C1 cams, and many of them (in M6 form) are making 380+ rwhp from the dyno charts I’ve seen. Seems like that extra lift must be doing something for them...

HP-GURU

Yeah, the extra lift gives them more duration where the stock head actually flows pretty well.

Since a square lobe is not an option ( you can't lift to max flow and hang there ), you have to overlift.

Seems simple...

GeorgeC

[quote]Originally posted by HP-GURU:
<strong>Yeah, the extra lift gives them more duration where the stock head actually flows pretty well.

Since a square lobe is not an option ( you can't lift to max flow and hang there ), you have to overlift.</strong><hr></blockquote>

That makes sense to me... With that in mind, I wonder how much more I could gain by even more lift than my .590 cam. I doubt I could go with much more on a hydraulic setup, but if I do jump over to a solid cam, maybe something in the .615-.620 range would be good? My heads (according to the flowsheets from GTP) peaked at .605" lift.

It would probably be a good idea to have my heads flow tested by a 3rd party since they'll be off the car soon.