330 Hp to 400 HP
09-20-2011 | 07:54 PM
#51
Registered
Joined: Sep 2011
Posts: 63
Likes: 0
What is the RPM range of the cam? Dry headers are pretty much a no go for most of us, dry to the tip is loud. Full dry is asking for serious trouble, so with that said your cam is going to have to work with a wet exhaust. Your engine is putting out 1.19 hp per cubic inch with really poor heads. I'm running IMO the best 454 head which is the AFR 265 Ovals, 9.9:1 compression and a custom cam, I'm also making 1.19 hp per c.i.. I have better heads, higher compression and a cam from one of the best cam guys in the marine world. I just don't see how you can make the same power per cubic inch. Dynos can vary a lot, unless both engines are dynoed on the same unit we're comparing apples to oranges in my opinion.
Last edited by Vortecpro; 09-20-2011 at 08:28 PM.
09-20-2011 | 10:02 PM
#52
Registered
Joined: Nov 2004
Posts: 14,090
Likes: 3,681
From: On A Dirt Floor
I’m not seeing a reason why that cam wouldn’t work w/ 112LC. If you read the 496 Dyno /myth busting article http://www.fullthrottlemarine.com/ HP loss would be minimum w/ a good wet exhaust system. The article says there is no HP improvement (“Next we removed the boat exhaust and routed it straight. No change”) over the Dana Marines. The article goes on to say the test engine lost 3hp to the Dana’s with Lightning headers.
As a super quick fyi: exhaust tuning (runner size, length and collector size and length) can help draw more intake charge. How's this ? During valve overlap. Most stock camshafts, including the 496, don't offer enough overlap for exhaust tuning to make big differences.
09-21-2011 | 08:43 AM
#54
Registered
Joined: May 2003
Posts: 87
Likes: 1
From: Jenison Mi.
I told you SAE.
Congratulations they are some good numbers and good luck on the Peanut port engine project.
Try this test 5800 for 20 minutes,now your in the boating world.
I will stick with Dart,AFR and Jesel.
Thanks
Dave
Congratulations they are some good numbers and good luck on the Peanut port engine project.
Try this test 5800 for 20 minutes,now your in the boating world.
I will stick with Dart,AFR and Jesel.
Thanks
Dave
09-21-2011 | 09:18 AM
#55
Registered
Joined: Jul 2006
Posts: 524
Likes: 2
From: Colorado
Guess I understand enough to get myself in trouble.
SB, If I understand you correctly your saying the overlap on the 496 cam in the article isn’t big enough to take advantage of a tuned exhaust? @ what overlap do you think a cam would benefit from a tuned exhaust… What is an example of a tuned exhaust? Vortec Pro says it would be significant on his 530hp motor? Neither the Dana Marines or the Lightning Headers are a cheap upgrade, how much HP loss are we talking about? The article says the Danas gain 23hp or 15.2hp w/ the turbulators removed over the stock exhaust system. Are we talking about another 15-20hp gain with a tuned header over a good wet exhaust?
SB, If I understand you correctly your saying the overlap on the 496 cam in the article isn’t big enough to take advantage of a tuned exhaust? @ what overlap do you think a cam would benefit from a tuned exhaust… What is an example of a tuned exhaust? Vortec Pro says it would be significant on his 530hp motor? Neither the Dana Marines or the Lightning Headers are a cheap upgrade, how much HP loss are we talking about? The article says the Danas gain 23hp or 15.2hp w/ the turbulators removed over the stock exhaust system. Are we talking about another 15-20hp gain with a tuned header over a good wet exhaust?
09-21-2011 | 01:53 PM
#56
MarineKinetics
Joined: Oct 2002
Posts: 942
Likes: 5
From: Rochester, NY
“. Air speed is the key here.”
Ok, good point. I don’t see any quantitative or qualitative data to support any comparative analysis here. No MCSA, localized velocity profiles, runner length, pitot data, etc. Absent data (of any kind) it would appear to be a rhetorical question.
Bob
09-21-2011 | 08:45 PM
#57
Registered
Joined: Sep 2011
Posts: 63
Likes: 0
SAE, well then theres another 4-5 percent on top of the wet exhaust. I use Dart and Jessel products when setting records and winning championships in heads up NA drag racing, with smooth idle 530 HP 454s I use peanut ports.
09-21-2011 | 08:57 PM
#58
Registered
Joined: Sep 2011
Posts: 63
Likes: 0
Thank you for that invitation, however, it does not appear there is anything of any substance to comment on here.
“. Air speed is the key here.”
Ok, good point. I don’t see any quantitative or qualitative data to support any comparative analysis here. No MCSA, localized velocity profiles, runner length, pitot data, etc. Absent data (of any kind) it would appear to be a rhetorical question.
Bob
“. Air speed is the key here.”
Ok, good point. I don’t see any quantitative or qualitative data to support any comparative analysis here. No MCSA, localized velocity profiles, runner length, pitot data, etc. Absent data (of any kind) it would appear to be a rhetorical question.
Bob
09-21-2011 | 09:28 PM
#59
Thread Starter
Registered
Joined: May 2009
Posts: 3,895
Likes: 124
From: Chicago, IL; Onekama, MI
Um, I don't remember Bob saying anything about a "mine is bigger than yours". Plus what would be the point of using the same compression and cam profiles? That would take all the knowledge and skill out of it. I would think a better comment would have been "it has to run on 87 octane and live at WTO for 20 minutes on the dyno and idle with full wet exhaust @ 600 rpms for 20 minutes!" To me that would make more sense!
09-21-2011 | 09:40 PM
#60
Registered
Joined: Sep 2011
Posts: 63
Likes: 0
Um, I don't remember Bob saying anything about a "mine is bigger than yours". Plus what would be the point of using the same compression and cam profiles? That would take all the knowledge and skill out of it. I would think a better comment would have been "it has to run on 87 octane and live at WTO for 20 minutes on the dyno and idle with full wet exhaust @ 600 rpms for 20 minutes!" To me that would make more sense!
