So, in the process of a head swap I noticed that the intake runners are significantly smaller that the gasket to the head. While the head very closely matches the intake gasket dimensions.
Anyone out there with dyno numbers on porting the intake manifold? Any theoretical value to porting the intake? Or is it better for the head ports to be larger than the intake?

Sorry about the poor pic I took with my phone.

 

Better to have the head ports larger than the manifold but best flow will always be with a smooth transition between the two. It could simply be production tolerances in the design to ensure there will never be a step inward from the manifold to head.

I'm not sure if anyone's done any testing to see what the gains may be.

 

This is a question for Jan at RMW, give him a call.

 

I was hoping Jan would chime-in and provide his opinion, as well as anyone else with some experience and hopefully data on this topic.

http://www.circletrack.com/techartic...ing/index.html

http://www.sa-motorsports.com/diyport.aspx

http://www.automedia.com/Port_Matchi...es20040801pm/1

http://www.tmossporting.com/tabid/3104/Default.aspx

Obviously some believe this is very important, but does this have actual value for ths engine/configuration?

 

When I did my RMW head I had noticed that the intake manifold was much smaller than the ports on the head. I asked Jan if I should port match it and he really didn't think it would make much difference. I think (Just an opinion) that since our cars are S/C that transistion isn't as important as on an N/A car.

 

That is what I meant by 'engine/configuration'. I have a similar suspicion, but I don't 'know', since I do not have any data (dyno numbers).

Anyone out there with some hard data?

 

ENDYN ports MINI intake manifolds. Give them a call.

http://theoldone.com/components/cyli...ead_modifi.htm

 

Thanks Astro,
Just gave a call, and an email with a link to this thread. Maybe we can get post from them for the benefit of us all.

 

Anti-reversion steps are beneficial for both NA and FI applications, although less critical for FI intake paths where higher boost pressures can forgive small sins. I don’t have hard data, but from a discussion I had with Corky Bell over transition issues, he considers perfecting intake path transitions low on the priority list; his recommendation “turn up the boost”, of course our Roots style SC has limitations.

Personally, I can’t let go of the obsession and feel every little bit helps. Take a look at the intercooler output duct, IM interface, and gasket, there is probably a mismatch at that location which can be improved upon also. The entrance to the IC output duct has a square shoulder that could be smoothed over or knife edged to provide some laminar flow benefit. Get a feel of the ICOD’s interior to make sure there are no giant casting flash blobs while you’re at it.

My stock head and intake manifold suffered from core shift in opposite directions; yours doesn’t appear to have that characteristic from what you’ve said. On my Endyn modified intake manifold and head, the IM gasket also required reshaping to match injector troughs and port profile. In the case of part manufacturing irregularities, or when you don’t want to leave any stone unturned in the pursuit of gains, or it is dictated by the head porter’s design, port matching the IM has more value.

 

Bingo, it's all little things combined with the big that really make a system work.

I have an RMW port matched intake on my car .

Longboard

 

Every little bit helps, but the most important thing to understand is going from the exhaust side to the header is more critical because you dont wanna suffocate, where from intake side going from smaller intake runners to bigger ported head is a transition that is easier if you will. Opening up is ok where squeezing down is an issue. There are many other factors but this is something that may ease minds. Matching is ultimate, so if it can be done. Do it.

 

Thanks for the input guys. I am just about done with the intake and SC horn porting. It is really pretty easy as Aluminum cuts like butta.

Obviously I am not sure how much performance this will deliver, but it damn sure can't hurt.

 

It will help!! a smooth transition into the head is criticle!! ( and most missed on head changes) Yes the Positive air from boost is LESS criticle than than the n/a engine. However with that said, the air will tumble and bubble at the ledge of the inter face!! How much HP loss?? I havent got that deep into a dyno testing to try and prove the loss in numbers... but with it all exposed, and you adding the cost to add a better flowing head, seems like you would also look for power in at least a gasket match between the Intake- Head- and HEADER!! Yes?? The power is there, and that might be why some are faster than others with the same mods... atten to detail!! LOL

( EDIT..)

Just me..............................

Thumper