Extrude Honed Intake Manifold on 3.1 Stroker

[E30arsen]

So I have a extrude honed intake manifold and I was wondering will this provide enough flow for a 3.1 stroker?
I know ITBs are the preferred setup, I just want to know will it strangle the engine dramatically like a stock manifold will.

[varg]

Nobody is going to be able to tell you for sure without flow numbers. Gotta try it to find out.

[ak-]

Nobody is going to be able to tell you for sure without flow numbers. Gotta try it to find out.

apostate can

[SkiFree]

"enough flow"?

DataPoint: I had a client in Europe about six years back who bought all the parts for a race-spec 3.1L M20 engine for his hill-climb car. He was constrained by his class to the stock intake manifold. After building the engine and maxing out every-other possible avenue, he chose to buy an extrude-honed manifold. He gained 1-2 horsepower throughout the power-band (difficult to accurately gauge this small of a change) up to a peak 7-8whp gain.

While it is proven to be a top-end power-adder for aggressive engines, the relatively high horse-power vs. dollar-spent doesn't make much sense for just about every other application. For a street-hotrod gains would be relatively unnoticeable.

If you have it, run it. It's better than nothing.

[sampayne]

apostate can

[e30davie]

But there would be levels of extrude honing yes? presumably you can take out more or less material making the runners anywhere from "slightly bigger than stock" to "hey i think we just put a hole in the runner wall"

How much bigger are we talking here? 5mm ID increase across the length of the runner?

Thinking outside the box, is M30 intake runners bigger? Perhaps a "simple" adaptor plate could adapt an m30 intake to an m20 and achieve similar results?

[dvallis]

There are some flow bench numbers on that around here. On my phone so I can't look for them. I remember results being a couple of HP improvement at most.

But like Ski said, if you've got it run it.

[digger]

extrude hone wont make the runners shorter to tune in at higher rpm ( stock length tunes in 3500-5000rpm) nor will it change the sharp curved bit right before it hits the head. all is does is make minor flow improvements which are never going to be earth shattering

i had a manifold done by a similar process here, abrasive flow or some BS. the only thing that changed was at the topend the power curve didnt nose over as fast but it was essentially a total waste of time and money. it wasn't the same process as EH but it was putty with some abrasive stuff in it they pump through.

better off cutting it up porting it and welding to together like MM do

[E30arsen]

Wow, I wasn't expecting this much info coming out. I am going to run it because I already have it, I just wanted to know how it would fair with the engine I'm building and it's been difficult finding good info on these intake manifolds. Thanks

[LowR3V'in]

basically if you think you feel a difference it's in your head. ;0