Lobe separation question

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kwilliams
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Lobe separation question

Post by kwilliams » Thu Apr 02, 2009 11:59 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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Wolfplace
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Re: Lobe separation question

Post by Wolfplace » Thu Apr 02, 2009 12:23 pm

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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Post by CamKing » Thu Apr 02, 2009 12:44 pm

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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kwilliams
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Post by kwilliams » Thu Apr 02, 2009 12:52 pm

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.

trmnatr

Post by trmnatr » Thu Apr 02, 2009 3:01 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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Post by andyf » Thu Apr 02, 2009 3:38 pm

The answer is 107.
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Post by F-BIRD'88 » Thu Apr 02, 2009 6:20 pm

How cheap is cheap? You can buy a generic oval track Elgin E1090P cam for $62 +shipping from CP.

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Post by randy331 » Fri Apr 03, 2009 12:25 am

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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Post by Stan Weiss » Fri Apr 03, 2009 12:55 am

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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