Cylinder head flow?

DRD · 08:07 PM

Guys, I have spent most of my engine building experience some 25 years, with VW air cooled engines, and have built some nice engines with some great dyno results. I own a 85, 911, and am looking to possible get into the High performance engine building of 911 engines. I do own a cylinder head flow bench and port my own heads, no porsche heads yet. I am looking for a cylinder head from the 911 engine to flow on my flow bench, on loan. I will pay the shipping cost. The the 3.2 head would be nice, but I would flow any head you guys have to extend my knowledge of the 911 engines and make more power.
Thanks
Darren

Wayne 962 · Wayne 962's Garage

Darren, I could probably send you one of my Porsche 3.2L twin plugged airplane heads. I've got another set coming in about 2 days...

-Wayne

island911 · 06-20-2002, 08:01 PM

More flow does not mean better performance. . .when it comes to 911's

DRD · 06-20-2002, 08:10 PM

The 911 engine is air pump reguardless. And if you really understand engines of any type , you will know what BMEP and cfm are realted to hp output!

island911 · 06-20-2002, 09:56 PM

Piston based air pumps do not need to mix fuel and air for starters.
To say "The 911 engine is air pump reguardless" reflects knowing just enough to be dangerous. . . or it may reflect an effort sell porting on the premise that more flow is better flow.

Of course I could be wrong . .. in which case everyone had better port their fuel injectors as well.
(because anyone, who really understand engines of any type, knows you need more fuel for more hp.)

Wayne 962 · Wayne 962's Garage

*sigh*

Why must the peacocks always strut their feathers...

-Wayne

DRD · 06-21-2002, 05:40 AM

Thanks Wayne,

island911 · 06-21-2002, 09:09 AM

Quote:

Originally posted by Wayne at Pelican Parts
*sigh*

Why must the peacocks always strut their feathers...

-Wayne

uhm. . .because they have fun feathers and no desire to write books?

Rich911E · Rich911E's Garage

Darren:

Don't you know that Porsche heads are perfect? Hasn't anyone told you that the valves are just exactly the right size in relation to the port size, gas speed flow, and camshaft profile? Haven't you figured out that the laws of physics don't apply in Stuttgart?

You might want to check out a thread on this very topic I started ages ago and that was the sum and substance of the replies. I have been trying to collaborate with somebody to do exactly what you suggest but have been unable to build a flow bench. I would be happy to help you out with whatever parts I can come up with. I have a couple of engines and am getting a set of 2.4 heads to work with.

Send me an e-mail and I would like to talk to you more about this.

Rich

82SC · 06-21-2002, 02:41 PM

well not to be redundant...

I have a set of single plug 3.2L heads sitting around collecting dust until I get enough mooola together for my engine...

the valves are all still in there so you would have to dismantle...

As long as I get a solomn promise that my heads are in good hands and they will not be molested you can borrow mine...

let me know

MJ

DRD · 06-21-2002, 03:38 PM

Rich, Very nice to hear from someone who has knowledge about engines. I am not the God of engines, but do understand them very well, and I have had some great experinces improving power output with many types of engines.
Porsche has done a good job with there engines, but there is still some room for improvement. Sadly we have some people that are so negetive that think they know it all, but there is allways few in the bunch.
A few post above said, you need more fuel to make more power, may be true, But you need to pump more air to be able to burn more fuel.
Anyway, E-mail and we can chat some more.
Darren

ChrisBennet · ChrisBennet's Garage

The 3.2 heads are supposed to be very good. Better than the 3.0 heads.
-Chris

911nut · 911nut's Garage

DRD,
Welcome to the bb where most of the "experts" have expertise only with their mouse.
You are not in the click yet so you can't possibly be a expert.

TimT · 06-21-2002, 05:32 PM

Porsche does such a thorough job developing their product. To "improve" on it in regards to performance usually takes "cubic money" you can put a porsche head on a flow bench and get some more flow out of it, but is the hp gain worth the money investment? Ill bet Porsches R&D has done what is needed.

my car started life as a humble 911T...... I opened my ports up to what porshce used in there race engines of that era, and spent alot of time with a die grinder dressing the heads. I saw so me significant hp gains on the dyno. But if I took an optimized porsche head and tried to improve on it...... i think more harm than good would be the result

Wayne 962 · Wayne 962's Garage

I'm not an expert on flowing heads by any means. However, from the conversations I have had with many, many people who are experts, all the power from the engine comes from the heads. This is of course true only in racing-land, where displacements and induction are kept to a strict number.

Again, this is what I have been told many, many times by people who have been doing this far longer than I have. These are the same people who are quite reluctant to give up their exact secrets!

-Wayne

HawgRyder · HawgRyder's Garage

Wayne....perhaps a good idea would be to ship a set of heads to Branch Flowmetrics and have them do their magic on them.
Then test the result....if there is improvement..OK
If there is not much improvement...that would answer the question once and for all.
Bob

Jim T · 06-22-2002, 07:58 AM

Quote:

Originally posted by 911nut
DRD,
Welcome to the bb where most of the "experts" have expertise only with their mouse.
You are not in the click yet so you can't possibly be a expert.

Or only with books. Lots of the supposed "experts" here give advice on cars they've never owned, never driven, never worked on, and, quite frankly, have probably never even really seen up close.

Leading to wrong information.

island911 · 06-22-2002, 08:45 AM

Jim, is that what you see in this thread? If so, where?

While I have ported heads and I get paid to do CFD (computational fluid dynamics) on air flows; I never claimed expertise in combustion chamber flows.
In fact, I know just enough to know that I am far from being an expert. . . but not so naive to think getting better performance out of carrera 3.2 engine is going to come from molesting the ports.

I know I don’t need to be a professional diver to call a belly-flop when I see one.

john walker's workshop · 06-22-2002, 08:51 AM

i would have to agree on the 3.2 port thing. if you ever have a chance to look at a 3.2 head, you would be scratching your head and wondering how you could improve the flow over what the factory did. the ports are already huge. some light smoothing is about all that's necessary.

Jim T · 06-22-2002, 09:39 AM

Quote:

Originally posted by island911
Jim, is that what you see in this thread? If so, where?

While I have ported heads and I get paid to do CFD (computational fluid dynamics) on air flows; I never claimed expertise in combustion chamber flows.
In fact, I know just enough to know that I am far from being an expert. . . but not so naive to think getting better performance out of carrera 3.2 engine is going to come from molesting the ports.

I know I don’t need to be a professional diver to call a belly-flop when I see one.

Oh, not at all. You are not one of the people I was thinking of.