More compression worth the cost?

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bOb shingler said:
that cam will not get you anywhere close to the 11.50 range but you'll get to the 13.00 range.
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please do explain.......

i dont have the cam card in front of me but it is a solid lifter mech. cam.

.525 lift
294 duration
110 degree lobe seperation
106 degree intake centerliine.

why do you think this cam is a dog? what would you recommend?

my pistons are true flat tops with no valve reliefs.
 
bOb shingler said:
that cam will not get you anywhere close to the 11.50 range but you'll get to the 13.00 range.
Click to expand...


no reply? well thanks for the very in depth and educational advise. good to know that i can always count on people that know more than i do to help me out.
 
I don't understand why your snapping at someone for not replying. But anyways Why don't you race it as is get her setup to get the best times you can get keep us posted than we can come up with ideas to help you to get into the 11's sound like it would be in 12's now to me. Bench racing only gets you so far track time is what you need. Don't take this the wrong way why didn't go with high compression piston during the build?
 
with 145 ish posts you should try not to burn bridges... unlike me most people arn't on here 4 times a day every day lol... so they might ot get back to you right away...

but the problem is with more cam (higher duration and a lower LSA) is that it has higher overlap... now over lap allows compression bleed off at lower rpms... so you have 8.5-9:1 comp STATIC... so with a 294 ADV duration, probably like 250ish @ .050, your losing alot of compression...

if it were me i would run it and see what it does... then either do a cam swap, run the numbers and figure out what is needed to get your DYNAMIC compression up to around 8.2 or so... then you can run 91 pump and get the most out of your combo for the time being...
 
Could run it enjoy it as is and build a stroker 400 bottom end and swap the top end when ready cause gonna be hard to go faster with your low compression engine, your cam probably too bigger for your CR now so I doubt you can go bigger cam for more power unless you go roller.
 
bOb shingler said:
that cam will not get you anywhere close to the 11.50 range but you'll get to the 13.00 range.
Click to expand...
I disagree with that. I have a 64 Sport
fury with a .030 440, .515/.515 223* 230*Hughes cam torker 2 intake, 750 Demon, 2500 stall converter,391 locker rear. It's run a best of 12.12 @110 launching at 1200rpm and shifting at 5500. Youi have a lighter car, slightly bigger cam,more gear,converter.If you spend time working with your combo, meaning launch, shift points,traction,timing and carb,you should be into the low 12s. My car started at 13.20s and just tuning and carb, and finding what the car liked, I cut over a second off my time.
 
273 said:
I don't understand why your snapping at someone for not replying. But anyways Why don't you race it as is get her setup to get the best times you can get keep us posted than we can come up with ideas to help you to get into the 11's sound like it would be in 12's now to me. Bench racing only gets you so far track time is what you need. Don't take this the wrong way why didn't go with high compression piston during the build?
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not snapping at anyone. the comment had no substance what so ever. it was a snide remark with no constructive qualities. i was asking the question to better my combination. i came to this board to hopefully build on my knowlege. this is my first build on my own and just trying to learn from my mistakes. if the cam is garbage thats fine. i would just like to know why.
 
younggun2.0 said:
not snapping at anyone. the comment had no substance what so ever. it was a snide remark with no constructive qualities. i was asking the question to better my combination. i came to this board to hopefully build on my knowlege. this is my first build on my own and just trying to learn from my mistakes. if the cam is garbage thats fine. i would just like to know why.
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then read my post... below

805moparkid said:
with 145 ish posts you should try not to burn bridges... unlike me most people arn't on here 4 times a day every day lol... so they might ot get back to you right away...

but the problem is with more cam (higher duration and a lower LSA) is that it has higher overlap... now over lap allows compression bleed off at lower rpms... so you have 8.5-9:1 comp STATIC... so with a 294 ADV duration, probably like 250ish @ .050, your losing alot of compression...

if it were me i would run it and see what it does... then either do a cam swap, run the numbers and figure out what is needed to get your DYNAMIC compression up to around 8.2 or so... then you can run 91 pump and get the most out of your combo for the time being...
Click to expand...
 
805moparkid said:
then read my post... below
Click to expand...


thank you for your post. i appreciate the explanation. so as i understand it, a cam with the same lift/duration and less overlap would provide less compression bleed off? where is the point that it becomes detrimental? is it all trial and error? i have been looking at some of the comp cams high energy cams with the faster ramp speed. I have read that mopars have larger diameter lifters then other engines and thus can cope with the stress of higher ramp speeds. is this also a way to cut back on the overlap?
 
Most cams have a recommend minimum compression there listed on their sites.
 
Your combo sounds pretty good. If your cam is the .525 lift Magnum hyd flat tappet, thats a pretty big cam 253 deg at .050 for 8.5-9 comp. Just install it 4 to 6 degrees advanced so that it closes the intake valve a little early this will help make more cylinder pressure helping make up for the low compression. I'd ditch the M-1 single plane for a Edelbrock Performer RPM, it will make far better low and mid range power and not give up a thing on top.
 
It's probably been mentioned somewhere and I missed it, but if you're using the speed pro flattops, then you may run into p/v clearance issues, and that's a pretty big cam for less than 9:1. Now I'm not knowledgeable on big blocks-yet-but, I'm pretty sure COMP shows recommendations for CR, carb size, stall, an gear ratios. It's been quite a while since I looked thru their catalog, but if you're rocking a 294S, I'm pretty sure COMP recommends 10:1 or higher CR...

Just my .02, and I'm sure I likely missed something throughout this discussion. It would probably sound good, but wouldn't build much pressure until higher RPMs.
 
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