![]() |
|
|
|
||||||
|
Quote:
Intake valve closes at 73 degrees ABDC @0.050" tappet lift. ![]() 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? Last edited by techinspector1; 12-17-2012 at 05:03 PM. |
|
|||||
|
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
Last edited by Horsepoweraddiction; 12-17-2012 at 05:14 PM. |
|
||||||
|
Quote:
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. Last edited by techinspector1; 12-17-2012 at 06:00 PM. |
|
||||||
|
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.
|
|
|||||
|
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?
|
|
||||||
|
Quote:
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. |
|
|||||
|
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.
|
|
||||||
|
Quote:
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-...-350-bore.html Last edited by techinspector1; 12-17-2012 at 08:00 PM. |
|
|||||
|
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.
|
|
||||||
|
Here's another option. Keep the 454 crank and rods and cam and heads you have, bore the block to +0.060" and use these pistons.....
JE Pistons 258205 BBC Closed Chamber Dome Piston Set 466 CID, 4.310 Bore, 4.000 Stroke, 0.06 Oversize Static compression ratio should be about 12.5:1, again, depending on chamber volume. |
|
||||||
|
You ain't just whistlin' Dixie, my friend.
|
|
|
| Recent Engine posts with photos |
| Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
| Thread Tools | |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| cam identification | ramman1500 | Engine | 6 | 01-29-2012 03:29 PM |
| Cam identification | Huntermike | Engine | 2 | 12-26-2011 10:04 AM |
| GM Cam Identification | Ricer Eater 78 | Engine | 5 | 05-25-2011 03:32 PM |
| Cam identification | PHATHOM | Engine | 2 | 06-06-2006 09:34 AM |
| Cam identification | 70bird | Engine | 2 | 05-24-2005 09:45 PM |