Ported Heads and Custom Cams

[VenemousStang]

My cobra has a built short block with 04 cobra heads and a Whipple 3.4 with all supporting mods. I'm trying to find more info on having my heads ported and adding custom cams. Looking at stage 3 port with new springs retainers valves etc. how much of a power difference will I see with ported heads over stock heads. Will be adding custom cams either way most likely so just want to see how big of a difference there will be in just the headwork. Looking to run around 25psi on e85 with the crusher setup. Trying to justify spending the amount of money on headwork is actually worth it. Any input is appreciated.

 

[VenemousStang]

Also anyone have insight about revving these heads close to 8k rpm

 

[lucheski]

the cams would probably be worth around 40hp the ported heads i'd guess 20 - 30hp

 

[KINGCOBRA86]

The heads and cams will drop the boost meaning the motor will be more efficient I was told with my built teksid block, ported heads and crower s 3 cams will get me a 5-10 % in rwhp increase, since I made 670 on 22 psi runing out of fuel at 18* timing
With a good fuel system and longtubes on the new motor I hope to gaing 70-90 rwhp over all

 

[gabe1530]

a well thought out combo can net you around 60-80hp increase. i would go with livernois stage 3 cnc porting or you could also go with fox lake.
get some custom cams to compliment the setup and have it degreed.

 

[VenemousStang]

Thanks for all the info just trying to make up my mind if it's worth puttin up the cash for heads. If the that amount of green is worth the gains haha

 

[VenemousStang]

Any insight on custom cams and springs to be able to rev higher?

 

[98 Saleen Cobra]

You need to contact a cam guy and tell him your goals and combo, and he'll design them around that.. Why would you want to spin 8000rpm with a 3.4? You're pushing the stock computer at that point like you wouldn't believe and it probably won't last long at all.

 

[Lstruck03]

Just for reference, with a stock longblock I made 517/584 with a ported Eaton on pump fuel and 20* timing. With ported navi heads and comp stg2 cams it made 567/555 on 17* timing.

Seems to me that with a better power adder the increases would be a higher percentage. I have since had a whipple and now a single setup but can't compare before and after since the engine work was already completed.

 

[RPM4DAZ]

I say yes on the heads. They will help bring up the efficiency through the whole power band. Provided they are done right. Make sure to pick a well known cylinder head guy. Brian Tooley at TEA is good choice. Livernois, Fox Lake and M2 systems are also well known. I would probably have the intake cleaned up at the ports into the plenum to match. Cams are yes for me also, but, don't go crazy on the duration. I would stay in the 220' @ .050" area and run the valve lift in the .490" - .500" range. More lift would just cause premature wear on the guides and springs for a street car. Bullet Cams has some nice lobe profiles that will get you there.

 

[VenemousStang]

To be honest 8k rpm is alittle high I was just looking into having my motor run up to maybe 7500 or alittle less. Just have more of a linear power curve that doesn't drop off at higher rpms. One that keeps going to at least 7000 rpm without dropping off.