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02-23-2016, 04:16 PM

#51

mggdoors

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My motor is roller. I know Spring open pressure is 125. Would have to look at sheet for close

02-23-2016, 04:21 PM

#52

mggdoors

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Install height is 1.880" giving you 110 lbs. of seat pressure and 345lbs. open, .560" max lift.

02-23-2016, 04:38 PM

#53

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well, throw my cam suggestion out the window.

02-23-2016, 04:39 PM

#54

GPM

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Quote:

Originally Posted by SB

Most definitely, however, I think the issue may be what I see is to be the lack of experience board wise, and maybe across the boards wise, with those heads.

Not knowing those, plus what valve spring open and closed psi's he has, plus retainer to valve seal clearance, but considering the compression, the cid's and the exhaust, I would think the following would get him closer to his goals, and choosing Lunati since that made several happy some days ago:

Lunati 20010721 (for Mark IV)
Hydraulic retrofit roller
272, 280 at .006"
221/227 at .050"
can't find lobe info for .200" duration
.575"/.575" lift
112 LSA

Great mid range torque and power. Likes
2000 RPM stall converter and works
great in towing applications with lower
gearing. Largest for inboard/outboard
performance marine use

Even with the 4.25 stroke

02-23-2016, 04:47 PM

#55

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Quote:

Originally Posted by GPM

Even with the 4.25 stroke

I know, would like more duration, but his hp goals and his exhaust....and the current Lunati factor....but, this is moot now because his springs won't handle much anyway.

02-23-2016, 04:48 PM

#56

GPM

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Quote:

Originally Posted by SB

I know, would like more duration, but his hp goals and his exhaust....and the current Lunati factor....but, this is moot now because his springs won't handle much anyway.

Yep.

02-23-2016, 05:28 PM

#57

mggdoors

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Buy a boat they said. It will be fun they said

02-23-2016, 05:29 PM

#58

getrdunn

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Quote:

Originally Posted by mggdoors

I know that according to forum search non stepped dominator a with 454 mags stock are cracking out 75-78 depending on conditions

Just as an example as a true honest comparison going back to 1993 I ran my 92 28' challenger with modified 480 plus/minus hp twins against a 32 sunsation with stock 454/365 mags. I was turning 5,600 plus with 25p mirage and ran btwn 75-77 mph in honest 2 to 3 footers. We ran from grand haven MI to Muskegon Mi. (12-13 miles). I hot lapped the guy about a 1/3 of the way to increase his pain since he bet me a 100.00 bill he'd take me easily.

Moral of the story is the dude had a very nice looking boat but was obvious his first day out with it and had a good salesman to boot. If I had to guess I'd say he was running high 60's low 70's tops. Needless to say he should have stayed parked in the party cove..

Last edited by getrdunn; 02-23-2016 at 05:32 PM.