yes, I agree... maybe Stephen can come down to texas ?? to give a hand
robert

 

If you are going to go down this path, make sure you get flow numbers before and after otherwise you have no clue as to efficiencies gained from the head work. We flowed our heads and made 302 CFM's on the exhaust side compared to stock at 244 and the RSR head at 260...It is a whole lot easier to tune and match fuel volumes with known flow numbers....Chad is right in his previous post...open up the engine and it gets expensive real fast since you keep saying" well, now is the time to do it"...Good luck.Kevin

 

Are your numbers flowed @ 25 or 28 inches water? I can't remember where ours flowed. I'll try to find them for a comparison.

 

I I already told you....I think 25 but I will check...

 

Flowed at 25� water. Inlet bell and Exhaust outlet used.

lift 0.050�, intake 52.3 cfm, exhaust 40.9 cfm
lift 0.100", intake 97.5 cfm, exhaust 92.2 cfm
lift 0.150", intake 144.0 cfm, exhaust 144.7 cfm
lift 0.200", intake 194.0 cfm, exhaust 179.2 cfm
lift 0.250", intake 237.6 cfm, exhaust 204.8 cfm
lift 0.300", intake 272.8 cfm, exhaust 225.3 cfm
lift 0.350", intake 297.3 cfm, exhaust 238.7 cfm
lift 0.400", intake 310.7 cfm, exhaust 250.9 cfm
lift 0.450", intake 320.9 cfm, exhaust 259.2 cfm
lift 0.500", intake 324.5 cfm, exhaust 266.2 cfm
lift 0.550", intake 327.2 cfm, exhaust 272.0 cfm

 

Heck , I am losing my mind with all these numbers...it was at 28 inches of H2O...Kevin

 

Chad, what is the difference between 25 and 28 inches ? Just a different standard?

 

Ken,

There are two standards. You can convert one to the other. It's just you can't get a good comparison between the two. If you convert 25" to 28", the 25's will look better. If you convert the 28" to 25", the numbers will become smaller.

 

Sort of like DynoJet and Mustang...lol

 

Yes, that would be a good comparison.


Here is some information for anyone who is interested about the stock 996tt intake cams.


Lift is .402" secondary cam lobe .118"

Duration .040 234 degrees .050 230 degrees

secondary cam duration .040 128 degrees .050 120 degrees

cam base circle 1.378

As a side note we have proven these cams will make power to 7500 rpm's.

 

If you want to determine how much hp your motor can generate based on your head flow capacity here it is.

cfm = cubic feet per minute

note* With a normally asperated motor to find hp

cfm x .27 x number of cylinders

To find hp for turbo motor:

hp(using NA hp formula) x boost +1 Atmosphere

You must know what you cam lift is because that is the maximum flow your heads can deliver at that lift.

 

Chad, we used a 100mm inlet bell...did you use the same size?Kevin

 

I'd have to look it up. I don't know off hand. Here are some pics of the heads, minor porting during flow testing and the bells used.

Ceramic coated combustion chambers/exhaust ports prior to valve job.
https://www.6speedonline.com/forums/...postcount=1822

Coated combustion chambers and Inconnel valves.
https://www.6speedonline.com/forums/...postcount=1823

Flow test bell.
https://www.6speedonline.com/forums/...postcount=1824

https://www.6speedonline.com/forums/...postcount=1825

https://www.6speedonline.com/forums/...postcount=1826

Touch up porting and marks for additional touch up porting.
https://www.6speedonline.com/forums/...postcount=1829

https://www.6speedonline.com/forums/...postcount=1830

 

Rob sorry to hear man, let the building begin though Goodluck

 

Yes I am waiting everyone who is involved to send me quotes!! I would like to get start in one week
robert