just for my own information, how much is too much overlap on a cam if you ever want to go with a supercharger?

or am I backwards and its actually a turbo where you don't want too much overlap?

I know compression needs to be around stock (for a slant), but I was wondering about the cam in case I decide to go with one in the future.

Camshaft doesn't know/care whether the forced induction system is belt-driven or exhaust-driven. You want very short overlap with forced induction, or a bunch of your boost (and raw fuel) gets shoved right out the exhaust valve.

Compression generally wants to be lower than stock (even on a slant) with forced induction.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

okay, so does anyone have a estimated number of what is too much overlap then?

is there any sort of formula, say something like x amount of boost is the limit for x amount of overlap?

I am just trying to track down some numbers, I believe my cam over lap is 350 at .050.

I am trying to decide on a higher compression ( I shaved the head .090, am undecided for decking the block....again....) or to leave it lower for a possible supercharger later.

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okay, I am lost here.

I have a new clifford cam, not stock. .498 and .5 lift.

so.....how much overlap is too much for a supercharger?

I am guessing there are no set in stone numbers, but I was hoping someone may have a round-about guess.

I'm with Panic here, although I'm no expert. Turbo setup should need less overlap than a blower. People have run blowers with hotter cams than you have, but not much boost (3-6 psi?). What type of blower do you want to use and how much boost? How much power are you after? Streetability?

Terry Littlejohn, who is on this board sometimes, has a blower with a biggish cam and fairly high comp on his Slant drag car.

Lou

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Home of Slant6-powered fun machines since 1988

I am just looking for what possibilities there may be in the future, as in if someday I decide to go with the supercharger, not really interested in a turbo.

I was wondering if the existing cam (my new clifford) was going to prevent me from one day going that far. I only really want to gut the internals once.

the car will be a weekend warrior type, not a daily driver. just cruising and running over fords.

looking for more ponies more than anything.

(also running a 3-spd with 3.23 rear 8 3/4 sure grip.....looking into 4 or 5 speed)

there is a ford with 250 6 cilinder running 12 psi of boost with a 224@.050 cam

http://www.cardomain.com/ride/686815

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http://www.cardomain.com/id/lncognito

If you are going to do something as a turbo or a supercharger you are going to plan your engine around that. If you go to that expense to do it right then you will build your project so it is right. Right camshaft right compression ratio right boast on the air enhancher right fuel system head work. To put a 2500 dollar supercharger on a car and expect to see a 10 second car is not priactial. Doint get me wrong but a supercharger has to be thought out and if done correctly is awsome. Thanks Ron Parker







Hell Hath No Wrath Than A Possum Scorned

thanks, but I do realize that ron.

what I am trying to get an answer to, and I beleive dart270 may have already answered it, was I just wanted to know if the cam I had chosen for my original build up would prevent me from using a supercharger in the future.

I didn't know the limits for overlap on a supercharger cam. thats all. I was just admiting I didn't really know much about superchargers, and wanted to see what people that had done them had to say about my cam choice.

so thanks to everyone for answering, I think I got it. looks like I haven't limited myself in the cam I choose.

I have checked out some posts on superchargers here, but I can't seem to get specifics (hard, actual numbers on the limits that is) on valve work and cams. I just want to know who took one to the limit and failed so I have an idea to work from.

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thats all folks, thats all I asked.

Had a bit of a discussion related to this a while back
http://www.slantsix.org/forum/viewtopic ... &view=next
I'm with Panic here . . . not sure what you're current LSA is but my current cam has a LSA of 110 and I believe I'm getting some blow thru.

For what its worth, my new cam (sitting on shelf for a year now, my upcoming winter project) from Engle designed with my blower in mind has a LSA of 112.

Intake lift at 0.02 = 0.483, cam duration @ 0.050"=232', lash at 0.018" Opens at 8' BTDC
Exhaust lift at 0.02=0.489, cam duration @ 0.050" = 237, lash at 0.020". Closes at 2' ATDC
Overlap at TDC is 10'

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Cheers!
Al T

over in the slixers gallery, I am posting everything about my engine (sick6's duster) and car. I have one other thing to post about my cam once I get home later today........

I just didn't want to double post, but I have posted a picture of the sheet I got from clifford about my cam, one more pic (of the spec sheet) to put up there though.

I'll write more when I get the chance.......