need help on cam choice

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340plot

340plot

the bushy bush
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ok. i have a 70 340. it had 12 to 1 pistons, and i had them cut down. they will now be about 10.2 to 1. have a old school holley strip dominator intake. holley 750 carb. going with 3:55 gears. do not know if i am going 4 speed or staying with the auto for now. i will be running headers. not sure of which ones yet.

the heads are 2:05 1:60 valved. it is setup with the 273 solid lifers.

i am looking for about 400+ out of the engine, but will run 93 pump gas only.

what is my best cam for this app. not much track use. just a stout driver. am i able to still use the solid lifters that were in this engine? they are new, but the cam is monsterous.

any help would be appreciated, and some part numbers will help also. i want it to have some lope, but not to where the car dies at idle
 
IMO If you want off the shelf and good power and sound you really cannot beat this cam in your application,I have ran it a few times. http://www.lunatipower.com/Product.aspx?id=1530&gid=277 If you look at the lift vs. duration its a pretty aggressive cam-slightly better than the comp xe series and as for the idle as lunati tech guy says its the original thumpr cam lol. http://www.lunatipower.com/Product.aspx?id=1546&gid=287 This is also a great grind,slightly more aggressive and you could have them custom grind it on a 108 lobe seperation for a more aggressive idle for a few bucks more, just a couple suggestions.I would not bother with a solid for what you are doing,and I would not reuse lifters.
 
Is the compression measured to be 10.2:1? Or you think i is now because you milled them? If it's measured at that, I would caution you against going with a high cylinder pressure cam. Of the two noted, I'd go with the first one.
 
I agree, the first cam looks very good for this applcation. Good choice Lead.

Ported heads or not?
 
the heads are not prted, but look to be blended into the intake
 
Lol!

If you know the chamber cc's of each to be even and equate with a stock open/close* cam, then you will want to run a cam that has at least 64* of overlap with pump gas.

Open chamber without prep & you might find 180lbs dynamic to be the limit w/91.

depends on the octane of fuel you have at the pump
 
here we have 93 octane. so do you have a part number for that cam you specify above, wild?
 
The overlap amount is a known for any cam and not to any one specific cam. Just look at the cam specs for any cam your thinking of.
 
The only problem with calculating overlap is if your not doing at .050 it can be misleading depending on what the cam designer measured advertised at.The first lunati cam I suggested made 175 cranking psi in my 340 at zero elevation,the dynamic winds up close to 8.7.The 340 has trws with 6cc valve reliefs,.025 above deck,66cc heads with std. felpro head gaskets at .045 compressed to get 10.14 compression.
 
so the lunati, i come up with 69* o lap w/285* on a 108.
the other cam is borderline too small @ 60* o lap

but hell...you can run a thicker head gasket to accommodate the smaller 60* cam, which will have better low end.
 
1wild&crazyguy said:
so the lunati, i come up with 69* o lap w/285* on a 108.
the other cam is borderline too small @ 60* o lap

but hell...you can run a thicker head gasket to accommodate the smaller 60* cam, which will have better low end.
Click to expand...

I knew a girl in school with really good low end.
 
I like the xe285hl for the '70* o lap braket' over the lunati,the other cam I like is the xe284h.
but are the heads setup for that much lift?

The xs282s is the ticket, or my 1st pick cause I like solid cams and this put the o lap in a nice place @ 67*
 
I myself would not be so worried with the amount of overlap. This can be worked around.
 
well, since a good deal came up on a engine/4-speed setup, i will not b building this engine, as the one i am buying has a cam, roller rockers, and is built. thanks for the help guys
 
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