v8killer

What kind of RWHP gain can I expect with extruded intake and LR Stage2 head?

Currently I am 368rwhp @ 22lbs. 2.5L M-Tune on E85,60-1 turbo, 3" exhaust, SFR FMIC.

Engine is LR built Widefire/Oringed with Wossner rods and pistons.

kev951

If there is no change to the cylinder head (ie porting or larger valves.... most likely nothing 1-2 hp .. or you might even drop 1-2 hp) LR's intake manifold however will yield in a power increase.

v8killer

The LR Stage 2 head flows 232 cfm instead of the stock 180 cfm.

333pg333

Not sure the extruded intake will do much. The head should offer something. When do you dyno it?

azbanks

I have no idea what those will do to your RWHP but I am flat out excited to see you back in the game.

rlm328

delete

H.F.B.

Below is a pic of my extrude honed intake by LR (Thank you LR !). The others show the port with seat and the valve job done by my local work shop.
The extrude honing will increase the cross-section dimension of the intake manifold around 1mm (0.04"). So good port matching is required in order to avoid unnecessary turbulence.
I haven't dynoed the car yet, but I can tell you, I noticed the difference. Attached is an article from the porsche engineering magazine. There, Porsche explained the benefits of extrude honing (p. 29), in german called Strömungsschleifen which they applied for tuning their 911 Carrera S. Unfortunately only not in english, may be google could help.

v8killer

Thanks, ready to get back on the track.

Looks nice H.F.B.

JBrown

Looking foward to dyno #s.. I had mine done also a cam, ported head Springs and retainers

V2Rocket

...so what happened with this

that extrude-honed intake is a huge difference!

JBrown

Dyno results yet ?

refresh951

I am not sure extrude honed intake will do anything for power with that stage II head. I would put my money somewhere else.

I would flow test the head to verify LR numbers as I have found them to be often optimistic. From my experience, a properly ported stock head, with a very good valve job, flows about 205-215 at max stock lift (0.473") @ 28"WC. If we assume the stock head flows 185 cfm at stock lift (0.475') that is an improvement of around 25 cfm or 13.5%.

H.F.B.

I see it as a whole thing. When you port your intake, one part of the job is to remove the casting imperfections that don't promote the airflow. Why should I stop doing that just some inch behind the valves? Apart from that the smooth finish has far less surface area, than the cast finish. The cast finish works more or less a bit like a heat sink. So with the smooth finish, the airflow picks up far less heat from the walls of the intake. Now with the extrude honed intake manifold this benefit is extended. Cooler air more power.
In addition, a smooth intake system reflects the resonant frequency between the plenum and the tube much better. So from my point of view it's simply a more complete head work.
Nevertheless a 2.8-3.1l hybrid stroker will be my next project.

refresh951

Just trying to share some of my experience. I have a flow bench and have done a lot of testing.

Unless you get to very high power levels, the port cross sectional area upstream of the guide does not play a significant role. You actual want the surface finish rough to promote turbulent flow. My point is that the stock intake significantly outflows the head port unless you have a big power motor with a much better than Stage II head. No harm in cleaning things up at the runners but my testing has shown it will not make a significant difference with respect to power.

Voith

Rough finish promotes laminar flow, smooth finish causes turbulences..