Single Plane Intake Manifolds.
#11
Banned
Join Date: Jan 2005
Location: Tri-Cities, TN
Posts: 648
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
Combination, Combination, Combination. Please let the cam be the second to the last thing you select. . . last being correct pushrods.
Chris
Chris
#14
MarineKinetics
![](https://www.offshoreonly.com/forums/images/icons/platinum_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
Russ,
We were recently involved in a dyno test of a HP 500 conversion. The engine was AFR 305 CNC chamber, custom cam and lifters; the rest was box stock HP 500. Between pulls 19 and 20 the change was made from the stock Dart unit to an Edelbrock 454 R Victor Jr. We cammed the engine for peak torque @ 4200-4400 and due to the limiter the engine peak HP had to land @ 5500 rpm. In comparison the torque curve remained comparatively consistent below peak torque (4400 rpm) with a 1.9 lb/ft delta. The significant difference came in the ability of the engine to maintain the integrity of the torque curve past peak up to peak HP. At 5500 rpm the Edelbrock held a 10.1HP advantage. Average torque/HP from 4500-5500 increased 7.1 lbs/ft & 6.7 HP. Had the engine not been cammed for a marine application and been run to 6500+, the advantage would have been significantly greater. The Eddy really cleaned up the fuel curve in the process. In this case the cam profile continued to dictate the peaks but the intake maintained the curve after peak torque. I agree, all single planes are not equal, however with so many variables involved it would be impossible to predict the results accurately without this kind of testing.
Bob
We were recently involved in a dyno test of a HP 500 conversion. The engine was AFR 305 CNC chamber, custom cam and lifters; the rest was box stock HP 500. Between pulls 19 and 20 the change was made from the stock Dart unit to an Edelbrock 454 R Victor Jr. We cammed the engine for peak torque @ 4200-4400 and due to the limiter the engine peak HP had to land @ 5500 rpm. In comparison the torque curve remained comparatively consistent below peak torque (4400 rpm) with a 1.9 lb/ft delta. The significant difference came in the ability of the engine to maintain the integrity of the torque curve past peak up to peak HP. At 5500 rpm the Edelbrock held a 10.1HP advantage. Average torque/HP from 4500-5500 increased 7.1 lbs/ft & 6.7 HP. Had the engine not been cammed for a marine application and been run to 6500+, the advantage would have been significantly greater. The Eddy really cleaned up the fuel curve in the process. In this case the cam profile continued to dictate the peaks but the intake maintained the curve after peak torque. I agree, all single planes are not equal, however with so many variables involved it would be impossible to predict the results accurately without this kind of testing.
Bob
#15
~~~~
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
Thread Starter
![Default](/forums/images/icons/icon1.gif)
Bob,
Those are interesting results.
Are you at liberty to share the peak numbers?
What does the HP500 use for carburetion?
Russ
Those are interesting results.
Are you at liberty to share the peak numbers?
What does the HP500 use for carburetion?
Russ
#16
Gold Member
![](https://www.offshoreonly.com/forums/images/icons/gold_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
Hopefully in about 6-8 weeks we will have another set of engines to compare. Mine will be 548 CI. Bobs(Rmbuilder) got my AFR 305 CNC chamber heads on order and is working on a cam. Right now I also have Victor 454R intakes and stock 1050 dominators I'm hoping to reuse. I think we are going to try to get my peak hp around 5600-5700.
Thread
Thread Starter
Forum
Replies
Last Post
HTRDLNCN
Swap Shop
0
08-20-2008 08:06 PM
blue64drop
General Q & A
6
11-11-2002 11:46 AM