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Lobe separation question

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Lobe separation question

Postby kwilliams » Thu Apr 02, 2009 10:59 am

My SBC 388 let go a few weekends ago and damaged my favorite little Erson solid flat tappet cam I had in it. Money is tight right now and trying to get the motor back in service as soon as I can I found a cheapo cam with a close lift and duration that I had. It's a 257/257 @ .050 .553/.561 lift on a 102LS, my Erson was similar to this but was on a 106. Will the 102 vs 106 LS hurt performance?

The motor is a 388 with pro action 210cc aluminum heads, super victor intake, E85 fuel, 12.75 compression, 3000 pound car, 5500 stall, 4.56 gears, 1/8th mile car.

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Kevin
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Re: Lobe separation question

Postby Wolfplace » Thu Apr 02, 2009 11:23 am

kwilliams wrote:My SBC 388 let go a few weekends ago and damaged my favorite little Erson solid flat tappet cam I had in it. Money is tight right now and trying to get the motor back in service as soon as I can I found a cheapo cam with a close lift and duration that I had. It's a 257/257 @ .050 .553/.561 lift on a 102LS, my Erson was similar to this but was on a 106. Will the 102 vs 106 LS hurt performance?

The motor is a 388 with pro action 210cc aluminum heads, super victor intake, E85 fuel, 12.75 compression, 3000 pound car, 5500 stall, 4.56 gears, 1/8th mile car.

Thanks,
Kevin

=
I think so but it might surprise you,, I would try it if you have it as I have found there are many times these engine do not read the same magazines we do,, :lol:
Watch the p/v clearance with the tight LSA
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Postby CamKing » Thu Apr 02, 2009 11:44 am

Are you sure the LSA is 102, or is the Intake Centerline 102?

Not too many cams are ground on 102 LSA.
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Postby kwilliams » Thu Apr 02, 2009 11:52 am

I just looked at it again to be sure and it says it's a 102 lobe separation. The notes say it's for a IMCA modified class or light stock car with 12:1 compression 4000-7100 rpm.
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Postby trmnatr » Thu Apr 02, 2009 2:01 pm

That 102 may be a little too tight in my opinion

If you have it try it but back the timing back a few degree as that cam should make more cylinder pressure than the old one and it may or may not push you into detonation

I see you have E85 so there should be no issues but............ Be carefull and try it
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Postby andyf » Thu Apr 02, 2009 2:38 pm

The answer is 107.
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Postby F-BIRD'88 » Thu Apr 02, 2009 5:20 pm

How cheap is cheap? You can buy a generic oval track Elgin E1090P cam for $62 +shipping from CP.
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Postby randy331 » Thu Apr 02, 2009 11:25 pm

trmnatr wrote:If you have it try it but back the timing back a few degree as that cam should make more cylinder pressure than the old one and it may or may not push you into detonation


Why would you assume cylinder pressure will be higher with this cam,vs his old one?

Let me guess dynamic compression?? :roll:

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Postby Stan Weiss » Thu Apr 02, 2009 11:55 pm

randy331 wrote:
trmnatr wrote:If you have it try it but back the timing back a few degree as that cam should make more cylinder pressure than the old one and it may or may not push you into detonation


Why would you assume cylinder pressure will be higher with this cam,vs his old one?

Let me guess dynamic compression?? :roll:

Randy


So which cam will have higher Cranking Compression? :?
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