Cam and valvetrain longevity....??? low duration high lift...
09-29-2016, 07:45 PM
#682
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69 !
09-29-2016, 10:59 PM
#684
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Platinum Member
Geezus what a long thread... Not sure I've ever read one that long all at once. Makes me wanna smack all those responsible �� Good job ��
I must say, from the very beginning I assumed this mistress had stainless marine gen III exhaust, and then towards the very end I realize it's the originals. That's def a problem. No way in hell I would have expected them to support 700hp, especially NA. General rules of thumb I've learned over the years, thru personal experience, friends, lots of online reading what other people learned, and in discussions with two local engine builders, who have dyno's and build marine performance engines - Jim Benny and Dave Gavatos (MDG), has led to the following very general conclusions, or "opinions":
-Gil manifolds = anything over 550hp NA and your def loosing power.
-Stainless Marine originals = A little better than Gil's, especially if supercharged. (The mistresses largest cork, my guess)
-CMI e-top type headers with no primary tubes in elbow section = not much better, if at all, than SM orig.
-Stainless Marine gen III = better than everything except full length large tube headers for NA, because the primaries continue into the elbows for a longer length than the e-tops, but close enough on most all boosted engines, especially after taking their reliability into account - are leaking headers (eventually) really worth the 20hp more when your boat will never notice the difference? A drag car might notice that small number, but not our resin buckets.
The only systems above I have not had personally are full length headers - heard too many leak stories for the money to be worth it in my small budgeted life so far. I have a set of CMI's hanging on my garage wall for decoration, Gil's buried in my shed, and currently run dry SM Gen III's on my 548.
I agree the intake may indeed be an issue too - dyno guys have been praising the victor and dart single planes for as long as I can remember, for a reason. Wilson charges a fortune for their work for a reason as well - it makes a difference. The intake manifold should be considered part of the head, and get the same attention on size and shape of runners, etc.
Ok, I really just wanted to make it onto page 69 ��
I must say, from the very beginning I assumed this mistress had stainless marine gen III exhaust, and then towards the very end I realize it's the originals. That's def a problem. No way in hell I would have expected them to support 700hp, especially NA. General rules of thumb I've learned over the years, thru personal experience, friends, lots of online reading what other people learned, and in discussions with two local engine builders, who have dyno's and build marine performance engines - Jim Benny and Dave Gavatos (MDG), has led to the following very general conclusions, or "opinions":
-Gil manifolds = anything over 550hp NA and your def loosing power.
-Stainless Marine originals = A little better than Gil's, especially if supercharged. (The mistresses largest cork, my guess)
-CMI e-top type headers with no primary tubes in elbow section = not much better, if at all, than SM orig.
-Stainless Marine gen III = better than everything except full length large tube headers for NA, because the primaries continue into the elbows for a longer length than the e-tops, but close enough on most all boosted engines, especially after taking their reliability into account - are leaking headers (eventually) really worth the 20hp more when your boat will never notice the difference? A drag car might notice that small number, but not our resin buckets.
The only systems above I have not had personally are full length headers - heard too many leak stories for the money to be worth it in my small budgeted life so far. I have a set of CMI's hanging on my garage wall for decoration, Gil's buried in my shed, and currently run dry SM Gen III's on my 548.
I agree the intake may indeed be an issue too - dyno guys have been praising the victor and dart single planes for as long as I can remember, for a reason. Wilson charges a fortune for their work for a reason as well - it makes a difference. The intake manifold should be considered part of the head, and get the same attention on size and shape of runners, etc.
Ok, I really just wanted to make it onto page 69 ��
Last edited by Hang Time 27; 09-30-2016 at 05:11 AM.
09-30-2016, 08:45 AM
#687
Registered
Sounds like Tim has multiple small issues with his combo......with the question of reliability #1
What's sad is the so called professional he worked with to design his build and order parts from was well aware what parts Tim was re using , what requirements the build needed to be designed around, and even Tim's budget.
I bet if Bob sold exhaust he would recommend it more often............
What's sad is the so called professional he worked with to design his build and order parts from was well aware what parts Tim was re using , what requirements the build needed to be designed around, and even Tim's budget.
I bet if Bob sold exhaust he would recommend it more often............
09-30-2016, 09:09 AM
#690
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The only two things we used was the exhaust and intake manifold every single other part is brand-new And if he was so smart he would have told me I need a better exhaust
Sounds like Tim has multiple small issues with his combo......with the question of reliability #1
What's sad is the so called professional he worked with to design his build and order parts from was well aware what parts Tim was re using , what requirements the build needed to be designed around, and even Tim's budget.
I bet if Bob sold exhaust he would recommend it more often............
What's sad is the so called professional he worked with to design his build and order parts from was well aware what parts Tim was re using , what requirements the build needed to be designed around, and even Tim's budget.
I bet if Bob sold exhaust he would recommend it more often............
