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01-16-2015 | 03:31 PM

#51

GPM

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From: Pa

Quote:

Originally Posted by 14 apache

Not sure of the hours I have put on them. Valve train on old motors had 2.4 stainless valves it would tare up the intake lift ramps on camshaft. New builds are getting Titanium intake valves that have the Crn coating so camshaft will live and going with the .937 lifters and 55MM camshaft. My biggest problem is if you have a leaky header and don't know about it ****s stuff up.

Curious, what springs were you running with this set up ?

01-16-2015 | 04:26 PM

#52

14 apache

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From: Northport N.Y.

CT1542DML I never used this spring yet.
I ran the old comp cams spring it was 210 on the seat I think it was 2.000 spring height diameter was 1.560

01-16-2015 | 04:32 PM

#53

GPM

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From: Pa

Quote:

Originally Posted by 14 apache

CT1542DML I never used this spring yet.
I ran the old comp cams spring it was 210 on the seat I think it was 2.000 spring height diameter was 1.560

210 at the seat with a 2.4 valve ? in a symetrical head ? with that 276/284 cam ?

01-16-2015 | 04:32 PM

#54

14 apache

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From: Northport N.Y.

Quote:

Originally Posted by GPM

Dynoed with both heads, BB2 xtra made 1372 @6200. I never got a good pull with the CNC 1801 Big Duke only know I gained another 6 or so MPH.
And I was wrong about the cam, it was a Comp Cam 276/284 @.050 .782 lift.solid roller. Crower 68806 springs with the 2xtra's, 68848 and then Pac 1348 with the Big Duke.

That pac 1348 spring has big pressure how does it hold up?
The cam lift is that with lash?

01-16-2015 | 04:35 PM

#55

14 apache

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From: Northport N.Y.

Quote:

Originally Posted by GPM

210 at the seat with a 2.4 valve ? in a symetrical head ? with that 276/284 cam ?

HH383 Brodix head with stainless valve 2.400 yes #210 Don't forget NA

01-16-2015 | 04:36 PM

#56

14 apache

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From: Northport N.Y.

The valve train looked great other than the intake lobes getting torn up from opening the valve.

01-16-2015 | 04:37 PM

#57

GPM

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From: Pa

Quote:

Originally Posted by 14 apache

That pac 1348 spring has big pressure how does it hold up?

In my opinion thats what you need to control a 2.40 stainless valve in a Big Duke head. I used to run it up to 7500rpm at the shootouts, never had a lobe, lifter or spring problem.

01-16-2015 | 04:39 PM

#58

GPM

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From: Pa

Quote:

Originally Posted by 14 apache

The valve train looked great other than the intake lobes getting torn up from opening the valve.

The springs I ran on the dyno had 275 at the seat and floated at 5100rpm, the motor was making 1327hp at the time and then started bouncing all over the place.

01-16-2015 | 04:41 PM

#59

14 apache

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From: Northport N.Y.

Quote:

Originally Posted by GPM

In my opinion thats what you need to control a 2.40 stainless valve in a Big Duke head. I used to run it up to 7500rpm at the shootouts, never had a lobe, lifter or spring problem.

Yes with a stainless valve you need big pressure. My big dukes have titanium just to help the other parts out.