Recomendations for 2.6SS port size
 

I would like to get expert recommendation for port size for 2.6. Main components:
66mm t non cw crank, cross drilled
2.0 rods
92mm Mahle pistons around 10.5:1 with 2.2-2.7 head volume if not mistaken
DC60 cams
MFI or 46 Webers
twin plug

I tried to search but did not really find details. 38/38 or larger? 46 webers are with 40mm manifolds, is 40/38 or 40/40 too big? I understand it also depends how well you are able to do porting.
I need 250-260hp crank with car weight 2000lbs wet. 911e throttle bodies and stacks should be modified or carbs if MFI is too big challenge (as I don't have pump yet). Some mid range should still exist, our tracks are short. Or change to 2.8? I need to use muffler as max 100db is allowed and I believe Megaphones are too loud. All recommendations appreciated!

Also if someone has suitable set of heads for sale, I have wtb ad on sales section.

Samu,

Port size ties to engine size and RPM to make target horsepower. The question is what RPM range is the target and can you afford that RPM? High RPM = High$$$$. Give me your target RPM I can give you a target port area.

PFM,
I believe DC60 should bring me 5000 to 7500 range. But I don't want it to be dogs at 5000 or how do you say over there. Have to check again, but cam is just one element. Aim is wide powerband rather than peak power as class rules weight/power. I bet you know these well as I saw your posts on engine dyno thread. High rpm $$$ this only $$+ :) Service every 100 hours.

A 38mm intake with a 36mm exhaust port should get you there with room to grow. The throttle bodies should be opened up to match port size with a 40mm throttle plate. Stacks would be 40 and 46mm at the top.

Samujr,

How much of a hurry are you on a set of heads? I will have a set of heads that really perrfom up for sale pretty soon.

Have a set of extreme worked heads ( their HSR mods with about 2000 miles on the motor) on my 2.7SS that I am swapping out for their own cast/billet heads in about a month. The motor just put down 266 HP to the rear wheels right behind a Bruns 3.0 race motor that put down 297Hp.

I am trying to figure out how much to ask for them, if interested email me. I can also ask the shop what the port sizes are if that would help.

Jimmy

Hi,

FWIW,....I do have a set of fresh, CNC-flowed heads specifically configured for 92mm pistons and cylinders. These have all new valves, springs, retainers, keepers and have been twin-plugged. These have 38mm intakes and 36mm exhausts. Pics are available.

I did these for a client with a 2.8 litre engine who decided to postpone his project.

Please e-mail me directly for details.

Samu,

If you can fit either of the pro heads above into your build you will be miles ahead. If you have ported hundreds of Porsche heads and are sure of your abilities break out the grinder. If not both of the offers above have had great results. Steve's offer sounds like it is ready to roll.

Thank you Aaron, PFM, Steve and Jimmy. Your recommendations are highly appreciated. I know porting is not easy to do properly for 911 heads. I will check options available and go from there. Thank you PP!