Porting and Polishing the Intake

[VNMOUS]

Any ideas how much of again you might see by porting and polishing the intake. If I am one of the unlucky owners subject to the intake valve recall, I'd like to use that $300 to have this done while they are in there. What do you think?

 

[Fred(DrivingSchool)Kinder]

It is called extrude hone! but the benefit will depend on what is the air flow restriction, intake, heads etc. If the weakest link is not improved then the benefit will be of little to negative value. Like putting a large throttle body on a stock GENII.

So the experts on the flow of the new engine will have to jump in for the real answer.

 

[VNMOUS]

I could be wrong but I believe that the term extrude hone refers to the manufacturing process of the intake manifold itself. Here in lies the actual problem with the intake valves that had not been completely through their 2nd stage of machining. Aif flow is decreased do to the fact that the surfaces are not as smooth as possible. By actually spending some quality time polishing and thus smoothing out all of the inner surfaces of the intake etc. you will dramatically increase the air flow. Essentially, more air flow equals more HP to a certain extent assuming you have the correct fuel supply to create the energy. I know several mustang guys that have done this to their "extrude honed" intakes and recieved dramatic increases in RWHP from it on the modular Cobra mortors. I am by no means an expert in this area so correct me if I am wrong. The real question--is the intake etc. already machined so well that this would be a waste of money, and does anyone with a prior generation Viper done this to find out?

 

[CHAD]

Extrude Hone is a company that patented the process of porting and polishing through the use of gel-like abrasive media. Like Fred said, power differences will depend on how that part matches the rest of the assembly. My guess is that slight gains could be noticed due to the stock manifold not being as polished as the EH'd manifold because of associated costs involved in making a part of that quality. Production parts are usually not up to the same standards as aftermarket, specialty parts and processes. It's the nature of the production beast.

Chad

 

[Vipermed 97.01]

It is called extrude hone! but the benefit will depend on what is the air flow restriction, intake, heads etc. If the weakest link is not improved then the benefit will be of little to negative value. Like putting a large throttle body on a stock GENII.

So the experts on the flow of the new engine will have to jump in for the real answer.

Fred you are correct.....One of the advantages of the gen3 engine is the fact that they have considerably decreased the length of the intake runners which has always been a downfall of the gen1s and 2s.As D.C has done a pretty good job at port matching the intake and heads, to do one without the other would be in vain especially in the case of doing the intake and not the heads.That being said,you would have some gains by polishing out the factory(rough) castings out of both creating less resistence hence better flow,in the case of this manifold with the size of the runners it would not be that much of an undertaking.The trick would be getting your tech to part with them or possibly helping you with your needs

 

[Fred(DrivingSchool)Kinder]

Chad is correct for more info see the following:

http://www.extrudehone.com/

The new motor would likely have very little benefit. The lead time was 8 weeks when my GENII intake was done.

Vipermed seems to be well informed on this as well.

 

[VNMOUS]

Thanks for the info guys

Austin

 

[Greg Good Cylinder Heads]

vnmous, if I were you I would work on the heads first, then the intake manifold. If your budget allows, do both. If not, you can always do the manifold later. You don't have to fully port the heads. Even just a multi-angle valve job along with blending the valve pockets and matching the intake port to a stock gasket would help significantly. It wouldn't be a "might pick you up" proposition. You would definitely feel the difference in the seat of your pants. This work can be done pretty quickly by a local performance machine shop. It usually only takes a few days. All you would need to do is shop around for the right machine shop and schedule some time with them so that your stuff gets worked on as soon as you drop it off. That way your car is not down long.

The valve job and bowl blend will pick up air flow on both the intake and the exhaust ports. But the intake ports gets the added gain of better air/fuel mixture quality. This is due to removing sharp edges and abrupt flow direction changes that cause air/fuel seperation. So in essence you'd be increasing flow quantity AND improving mixture quality at the same time.

It makes no sense to port the manifold without doing the heads, and it could even hurt flow and power if the manifold is opened up larger than the intake port on the head. This would be the case if you matched the manifold to the intake gasket, but did not do the same thing to the heads. This would allow any part of the intake flange of the head that is inside the gasket line to protrude into the flow path, causing turbulence, which hurts flow and power.

 

[Tom Welch]

Some things about Viper mods are useless money pits unless you wish to have an unrealistically high horsepower, undrivable car. Extrude Honing the intake is one of these useless mods. An example, we are making 1000 Rear Wheel Torque with a stock Viper Intake Manifold and Throttle Bodies. In my opinion, its' a correct combination of components that will make your car perform at its peak, not just hogging till the cows come home. If you don't beleive it, search the archives of this site for horsepower loss from adding big Throttle bodies to a stock Viper.

Good Luck,

Tom

 

[RC Viper]

So what would you expect to pay for porting and polishing Viper heads if they were already removed?