Offshoreonly.com
Page 6 of 6
« First
4
5
6
Show 40 post(s) from this thread on one page

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   Experts: Runner length and volume? (https://www.offshoreonly.com/forums/general-q/93612-experts-runner-length-volume.html)

articfriends 01-07-2005 08:37 PM
Re: Experts: Runner length and volume?
 
Originally Posted by kennywould
Hehe...your killing me Smitty! John doesn't know it's missing yet! yep, runnin a 96/272 Baja, I seem to have a problem with the haul, haven't busted 80 yet! Should start another thread for this maybe? Do you talk as fast as you type? :D :D
-Ken
Ken,my boat stops accellerating completely at 78-80 mph UNLESS its trimmed right to max but i'm sure youve already tried this with your boat. I'm turning a 30 pitch lab at 5400 with ALOT of slip. I bought a 32 pitch from houston prop in the fall,boat went 84.7(if i remember right)but next season i'm hoping to see 90mph. I also had smallest blower pulley on with 32 pitch(i was seeing 5200 ). At beginning of this season my motor still had less than 10% leakdown,at end of season i had cylinders at 35% :eek: ,motor has 140 hours(2 seasons) on it,i'm freshening it this winter and changing cam,putting afr cnc's on it and bigger injectors and doing something with intake(still undecided),Smitty

WETTE VETTE 01-07-2005 08:40 PM
Re: Experts: Runner length and volume?
 
That makes sense GPM. I had a buddy that ran a 900 HP NA 632" (pump gas) and he ran a Dart tunnel ram. It was fully hand ported probably to get the intake to match his 420 CFM intake ports. So are you going to tell us what was different on the motors between the earlier mentioned dyno pulls? I am assuming you know the answer and are just testing us. Maybe it is the differance between an older Procharger vs the M5. Give us a hint!! :drink:


Hey JIMV,

Ever flow heads with an intake bolted up and is it even possible?

Craig

GPM 01-07-2005 08:55 PM
Re: Experts: Runner length and volume?
 
It was the same motor, blower belt started slipping on the 1200hp one, slowed the blower down for the 1372. Imagine a cog system. We always check head flow through the manifold looking for restriction.

JimV 01-08-2005 09:31 AM
Re: Experts: Runner length and volume?
 
Originally Posted by WETTE VETTE
That makes sense GPM. I had a buddy that ran a 900 HP NA 632" (pump gas) and he ran a Dart tunnel ram. It was fully hand ported probably to get the intake to match his 420 CFM intake ports. So are you going to tell us what was different on the motors between the earlier mentioned dyno pulls? I am assuming you know the answer and are just testing us. Maybe it is the differance between an older Procharger vs the M5. Give us a hint!! :drink:


Hey JIMV,

Ever flow heads with an intake bolted up and is it even possible?

Craig
Craig, I do it all the time. The Dart manifold knocks the flow back about 6% depending on the runner. A tunnel ram about 3 %. I flow them with carbs, and the runners blocked off

Raylar 01-08-2005 11:13 AM
Re: Experts: Runner length and volume?
 
Chris:

Sorry for the delay the block is up at Roush in Detroit right now and they will be done with it on the 24th. I will get it to you then and you can start on our new trick oil pan.
Thanks for reminding me. so damn busy!
Regards,
Ray @ Raylar

GPM 01-09-2005 11:04 AM
Re: Experts: Runner length and volume?
 
Originally Posted by articfriends
GPM,what kind of fuel injection are you running,what are you controlling it with,who programmed it?What are you running for a innercooler and what kind of plumbing are you using to get air into intake,can you post a pic? I am upgrading my heads this winter and am looking for induction ideas to replace my 502 mag intake and fuel injection. I am running m-3sc on 540 blowing thru stock 502 mpi intake. What size injectors are you running and what kind of fuel pumps? What kind of hull are you running this in and what kind of drives? How good does it idle,are you running dry exhaust? Thanks,Smitty
Smitty, I found a picture, it's from a more recent project, tunnel ram EFI.

JimV 01-11-2005 10:07 AM
Re: Experts: Runner length and volume?
 
1 Attachment(s)
Heres my 565

2112 01-11-2005 10:22 AM
Re: Experts: Runner length and volume?
 
Originally Posted by Raylar
On the question about taper in the runners. Runners should taper approximatly 2% per inch of runner length from the opening towards the valve on a constant smooth basis if possible. This will increase velocity and the ram effect. As for which benefits more, runner redirection is more critical in a wet( carburated) manifold, because when wet air changes direction(curves) it will let more fuel drop out of suspension. Remember fuel (heavier) and air don't weigh the same and hence change directions at different speeds. The runner length determines where the rpm power band of a manifold will be and the taper helps develop the speed of the charge.
Ray @ Raylar

In simple terms, the taller the intake (tunnel ram) the higher (rpm) the power band?

Raylar 01-12-2005 01:45 AM
Re: Experts: Runner length and volume?
 
No , not neccessarily. A taller tunnel ram with longer runners of the same area or size as a shorter tunnel ram would tend to have its max power at a lower rpm with more torque.
Longer runners generaly develop power at lower rpms and at very high rpms they tend to restrict the engines breathing ability and is obviously camshaft size and duration dependant.. Your intake, cam and exhaust system has to be tailored to where you want your power band.
Ray @ Raylar

tomcat 01-12-2005 10:38 PM
Re: Experts: Runner length and volume?
 
JimV: Is that a Dart tunnel ram on your engine? Where is the power band on that combo?


All times are GMT -5. The time now is 11:35 AM.
Page 6 of 6
« First
4
5
6
Show 40 post(s) from this thread on one page


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.