Valvesprings on LM-1 -- XE256 cam ok?
07-16-2003, 08:57 PM
#1
Race Director
Thread Starter
Valvesprings on LM-1 -- XE256 cam ok?
.447/.454 lift.
Will this be okay with the stock valvesprings on the LM-1 / GM GW 350?
Thanks in advance.
-Steve
Will this be okay with the stock valvesprings on the LM-1 / GM GW 350?
Thanks in advance.
-Steve
07-16-2003, 09:22 PM
#2
Safety Car
Re: Valvesprings on LM-1 -- XE256 cam ok? (Pacin'California)
whats an LM-1? just curious. anyway, in comp cams catalog they dont require a valve spring change from stock with that particular cam. One step up to the XE262 is where they begin to recomend the spring change.
07-16-2003, 10:33 PM
#3
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Re: Valvesprings on LM-1 -- XE256 cam ok? (Pacin'California)
Steve
The first cam I ran with the stock springs was .424/.444 lift, I don't think you should have a problem with that cam. I really wished I had stepped up one size on the cam when I first put the eng in. I bet you will like the low end grunt but still pull up to 5000 rpm's, maybe a bit more. Mine petered hard at 4500 but wa fun till then. :lol:
The first cam I ran with the stock springs was .424/.444 lift, I don't think you should have a problem with that cam. I really wished I had stepped up one size on the cam when I first put the eng in. I bet you will like the low end grunt but still pull up to 5000 rpm's, maybe a bit more. Mine petered hard at 4500 but wa fun till then. :lol:
07-17-2003, 10:20 AM
#5
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Re: Valvesprings on LM-1 -- XE256 cam ok? (Tominator)
I know the XE 262 requires specific springs and thought the entire XE line did, not so much because of lift but because of steep ramp profile of the cam. Best to check the Comp Cams website or call their tech support.
07-17-2003, 10:30 AM
#6
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Re: Valvesprings on LM-1 -- XE256 cam ok? (Pacin'California)
Come to think of it you might want do the cam break with the stock springs and if you find that it needs stronger springs you can do it later. Kinda follows the idea of using single springs to break in a high lift solid cam then switching to dual spings after break in.
07-17-2003, 02:49 PM
#8
Team Owner
Re: Valvesprings on LM-1 -- XE256 cam ok? (Pacin'California)
Steve your screwing up! I thought that your car was an L-82? I'm just trying to same you time and money. Way back when I installed a XE260 type cam and was very dissapointed when it ran the same as the L-82 cam.
I don't have the specs in front of me, but just off the top of my head the l-82 cam is @220 degrees at .050 with low .400 lift. So a cam like a XE256 is less duration and about the same lift. the only gain is some what steeper ramps and tighter lobe center. Your hp and tq would end up being @ the same.
The thing to buy is something like the Crane Power max Cam/lifters/and springs.
I can't make it to the American Lemans race on the 26th.
I don't have the specs in front of me, but just off the top of my head the l-82 cam is @220 degrees at .050 with low .400 lift. So a cam like a XE256 is less duration and about the same lift. the only gain is some what steeper ramps and tighter lobe center. Your hp and tq would end up being @ the same.
The thing to buy is something like the Crane Power max Cam/lifters/and springs.
I can't make it to the American Lemans race on the 26th.
07-17-2003, 03:06 PM
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Re: Valvesprings on LM-1 -- XE256 cam ok? (gkull)
George
He has the same base replacement eng I do, it is an LM1 with about 8.5/1 comp, wimpy cam and not so great heads.
He has the same base replacement eng I do, it is an LM1 with about 8.5/1 comp, wimpy cam and not so great heads.
07-17-2003, 03:18 PM
#10
Team Owner
Re: Valvesprings on LM-1 -- XE256 cam ok? (Fevre)
If it's a wimp with 8.5 CR. You need a cam that can build pressure with wide lobe centers.
So maybe the Crane 266 is a better choice. The 272 needs higher compression.
http://www.cranecams.com/master/apps...#3.%20PowerMax
So maybe the Crane 266 is a better choice. The 272 needs higher compression.
http://www.cranecams.com/master/apps...#3.%20PowerMax
07-17-2003, 11:01 PM
#12
Race Director
Thread Starter
Re: Valvesprings on LM-1 -- XE256 cam ok? (gkull)
Thanks for telling me about ALMS, George. I was still planning on buying tickets. Are you gonna go to Laguna this year?
Don't worry man, if I had an L-82, I would have known that switching the cam would have been in poor taste. :) The 266 also looks good, I was looking at that one also.
-Steve
Don't worry man, if I had an L-82, I would have known that switching the cam would have been in poor taste. :) The 266 also looks good, I was looking at that one also.
-Steve
07-18-2003, 10:06 AM
#13
Team Owner
Re: Valvesprings on LM-1 -- XE256 cam ok? (Pacin'California)
Get with "WENCHER" He told me that he's working the ALMS event. If you have never been to an American Lemans event it's something that you have to see. I started attending IMSA events in the 70's & 80's when the the cars were deafening:) The pits and padock are free to get into so take lots of pictures.
The Corvette coral is straight up the hill throught the main gate next to some of the best track view seating. Yours will be one of the few C-3's in a sea of c-5's. I'm sure that they would like your car.
The Corvette coral is straight up the hill throught the main gate next to some of the best track view seating. Yours will be one of the few C-3's in a sea of c-5's. I'm sure that they would like your car.
