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Discussion Starter · #1 ·
I've told some of you i have a couple 454s, well one i bought already had a cam in it , i would like to know what i should do next to the block and tell me a little more about this cam as in what size and such. pt no. 11-738-9(14) Thanks guys, one of the best forums ever
 

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I've told some of you i have a couple 454s, well one i bought already had a cam in it , i would like to know what i should do next to the block and tell me a little more about this cam as in what size and such. pt no. 11-738-9(14) Thanks guys, one of the best forums ever
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=523&sb=0
Intake valve closes at 73 degrees ABDC @0.050" tappet lift. :eek:
Check out the rpm range. Needs 13.0:1-15.0:1 SCR and race gasoline or methanol/ethanol.

What did you want the motor to do for you?
 

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Well to race it pretty much the guy told me he was gonna drag race it. what piston and head would work best? wouldnt dome pistions have clearance issues?I was thinking about making it a stroker motor too
Did you get any heads with the motor? If yes, give us details. Any pistons with the motor? If yes, give us details. Photos always help.

A stroker sounds like a good plan. The more cubic inches, the less piston dome you have to use to get to your target SCR.

Bored 0.100+ with a 4.250" crank will make a 505. This SRP 43cc piston will make the following SCR's...
14.0:1 with a 112cc chamber. You can buy 112cc heads off the shelf. Custom fitting of the piston dome to chamber surfaces may be necessary.
13.1:1 with a 118cc chamber.
http://www.summitracing.com/parts/srp-139834-1
14.0:1 with that cam will generate a 8.84:1 DCR.
 

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Discussion Starter · #5 ·
Yes i have a couple pictures , The block has already been bored 30 over hooker competition headers vic jr. nitrous intake, the heads were the 3919840 rectangle port.
 

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Yes i have a couple pictures , The block has already been bored 30 over hooker competition headers vic jr. nitrous intake, the heads were the 3919840 rectangle port.
3919840 67-69 396, 106.8cc chambers. The pistons look relatively flat according to what I can see. I'm guessin' that the motor was on the order of 9.0:1 SCR with a 5.81:1 DCR. I have no idea how the N2O changed things, but I can't see much cylinder pressure without the nitrous. Looks like maybe the guy built a turd and then had to spray it to get it out of its own way. Ridiculous amount of cam for the combo.
 

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Discussion Starter · #7 ·
Would i need to get alum heads? i know it would be better but how would those heads do? and yeah the guy talked a big game haha. and yeah those pistons were flat. And should i stick with those same pistons you recommended?
 

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Would i need to get alum heads? i know it would be better but how would those heads do? and yeah the guy talked a big game haha. and yeah those pistons were flat. And should i stick with those same pistons you recommended?
The biggest problem right now is the cam. I have explained in detail how to match parts to make the cam work for you. If you want to sell that cam and lifters on RacingJunk and start over with a different cam and a different combination of parts, then yes, you can use those heads you have. You will only need those pistons I linked if you plan to retain that super-humongous camshaft.

I'm not sure you understand, but the camshaft timing is directly linked to the static compression ratio. The most important event on the cam is the intake valve closing point. That's what determines the cylinder pressure, along with the static compression ratio. What this guy had going was a mild street motor static compression ratio of around 9.0:1, with a camshaft that wanted 14.0:1 static compression ratio. The cam was closing the intake valve so late that most of the air/fuel slug that had been drawn in, was pushed back up the intake tract as the piston ascended up the bore on its compression stroke, resulting in very low cylinder pressure. As I said earlier, I have no idea how the spray worked into all this. It certainly would have contributed to additional cylinder pressure over no spray, but if it would tip the scales and make a decent motor, I do not know.
 

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Discussion Starter · #9 ·
I understand a little bit, i read a post by you about the "rumpty-rump" something like that about cams being to large and compression not being high enough. But i plan to keep the cam and bore it 100. over and get the 4.250 crank plus the rods. Get those srp pistons to raise the compression.But i want to make sure i Can use these heads right? i'm not really worried about the nitrous much. Sorry about all the confusion man i appreciate everything.
 

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I understand a little bit, i read a post by you about the "rumpty-rump" something like that about cams being to large and compression not being high enough. But i plan to keep the cam and bore it 100. over and get the 4.250 crank plus the rods. Get those srp pistons to raise the compression.But i want to make sure i Can use these heads right? i'm not really worried about the nitrous much. Sorry about all the confusion man i appreciate everything.
The heads you have are closed-chamber heads and will not work with domed pistons like I linked. You need open-chamber heads to make them work. If you insist on using the heads you have, then you are limited to flat-top pistons or special closed-chamber pistons that will make acceptable static compression ratio for racing.

You could keep the heads and use Keith Black IC789-100 pistons. Bore the block +0.100" and use a 4.250" crank with 6.385" rods to make a 505. The pistons would yield approximately 12.0:1, depending on the chamber volume in the heads. That would still be a little light for the cam, but you could use it. If you'll cc the heads, I can figure it for you down to a gnat's butt hair.
http://www.cnc-motorsports.com/icon-ic789-100-forged-dome-pistons-4-350-bore.html
 

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Discussion Starter · #11 ·
Its gonna rid me of all my profits but i will save up for a new set of aluminum heads. and go with the rest of the plan. I've heard good things at cnc-motorsports but which company should i order the crank and rods from? You are a smart man no doubt lol What would you say the hp and torque numbers would be around? without nitrous that is.
 

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The difference between 468/505? depends on configuration.If everything is identical except the cubes,the 505 will make the same power(or a bit more because of the bore) but at a lower RPM.
 
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