Need advice--Camshaft degree issue (maybe??)

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OldBlueDually

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Had to do a double-take, I thought I was looking at my engine! Just degreed mine a few days ago it came up at 107.750 on a 108 desired Centerline.

I hate you!!! I mean, what I meant to say.....that is so fricken awesome, man I wish mine had gone like that!!!!

Torque is more fun than sound my friend.

I will still have some low end torque, probably not as much as with an RV cam or something, but still fun. Some year I plan to throw on a dual 4-bbl tunnel ram intake just for the looks, so that will probably decrease my lower end torque a bit too, but will look cool as heck!

Just read your last post. If LSA is 107 (214 at the crank), then "straight up" would be 107 ATDC. So with intake center line at 102 ATDC, that's 5 degrees advanced, as you said. But using a stock timing set you would still get 5 degrees advanced, not 9 degrees. Where am I wrong here? Is there +5 degrees built into the stock timing set?

As for the Thumpr cam, be sure to get a larger gas tank and very low axle ratio.:)

I do not know for sure to be honest, but with 5 degrees advance built into the cam......then my stock gearset after degreeing it coming out 4 degrees advanced......adds up to 9 overall in my head. Maybe I looked at this wrong, but either way my stock timing set was 4 degrees advanced and I don't like that....
 

shiftpro

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I I will still have some low end torque, probably not as much as with an RV cam or something, but still fun. Some year I plan to throw on a dual 4-bbl tunnel ram intake just for the looks, so that will probably decrease my lower end torque a bit too, but will look cool as heck![/QUOTE

You will be fine, just get yer darn degrees degreed.


Consider tunnel ram + high compression + propane fuel for looks and great street manners. You will for sure need a cam change though, something with
mucho higher (less) overlap. If you want to stick with SB then stroke it and minimum 10.1 compression. Two Impco 425s :burnout:
 

idahovette

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UH, no SBC this is a 455 OLDS
 

OldBlueDually

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No SB for this big ole' truck. I'm putting real power in it :D (sorry, I am biased towards Olds engines).


UH, no SBC this is a 455 OLDS

Yeah! What he said!!
 

shiftpro

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No SB for this big ole' truck. I'm putting real power in it :D (sorry, I am biased towards Olds engines).




Yeah! What he said!!
I said that wrong, I mean a dual carb tunnel ram and propane even works great on a SB. Sorry don't mean to high jack yer thread.
 

OldBlueDually

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I said that wrong, I mean a dual carb tunnel ram and propane even works great on a SB. Sorry don't mean to high jack yer thread.

Oh no worries, I am good at doing that myself too! :anitoof:
 

OldBlueDually

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@QBuff02 @MikeB @jeff406cid @shiftpro

I think I got it this time!!! Close enough!

I put on my new Cloyes timing gear set (BTW there was NOT 3 holes in the upper gear as the picture shows), but the 9 keyways with 2 degree cuts really helped.

I first did it to "stock" setting, and my number came out to be 97.75 which is 4.25 degrees advanced. SO, with past issues a guy would think "ok, retard it 4 degrees"....well my old gear set only had 4 degree advance/retard and it still wasn't close.

This time I retarded it by 2 degrees on the crank keyway, my number came out to be 100.75 which is 1.25 degrees advanced. (Cam calls for 102 degree centerline).

I "think" I am done now....I hope.
 

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