We just finished porting a set of heads for a N/A crossfire and since they are the same as the C32 heads I thought I'd share the results.

I'll try to get some pics up tomorrow, but here are the flow numbers.

Here are the flow numbers:

Stock:

.100" I:88.7 E:65.7
.200" I:167.5 E:118.6
.300" I:218.2 E:159.4
.400" I:217.8 E:177.6
.500" I:224.8 E:184.3

Modified:

.100" I:101.1 E:71.6
.200" I:195.3 E:117.8
.300" I:256.9 E:164.0
.400" I:296.0 E:192.3
.500" I:318.9 E:199.1

Gains:

.100" I:12.4 E:5.9
.200" I:27.8 E:-.8
.300" I:38.7 E:4.6
.400" I:78.2 E:14.7
.500" I:94.1 E:14.8

 

Forgive my ignorance, can you pls elaborate on the datum that you posted in layman terms?

 

Still not layman's terms. but here's the original thread:

http://www.crossfireforum.org/forum/crossfire-srt6/37364-head-work-done-216-318-cfm.html

 

Flow numbers are the amount of air at cubic feet per minute (cfm) flowed through the given valve at a specific lift (.x00"). The cam lobes are what give the lift or opening of the valves. Basically the idea is to maintain velocity and keep a good solid lift in the area where the cam is maximized. For these particular heads, the cam is happiest in the .350-.450, but it obvoiusly crosses both extremes.

The general rule for HP gain on a N/A motor is 2hp=1cfm. So if the motor itself can use the increased airflow (SC motors will benefit way more then the NA) then you could posssibly gain almost 200 HP from these heads. Realistically though it will depend on what your weak link is.

I would expect 50HP on the M112K with a modded motor. For the M112 I would expect 15-20HP. The limiting factor on these motors is the SC, so the heads will not really be able to shine until that bottle neck is taken care of. I have an extra SC sitting at the shop and I may just put it on the flow bench to see just how much it flows.

 

Sent PM.

 

i believe Jerry did this on his C32 and didnt pick up power . and he has the most heavily modded C32 probably, though makes less power than Jake's

http://dragtimes.com/Mercedes-Benz-C...lip-15891.html

 

I believe at the time Jerry tested he didn't have any major modification to the intake side of the car though. If the stock manifolds only flow 190cfm, a head that flows 250cfm is only going to use 190cfm.

Every head porter is different. I've sen people lose power with improper porting and then with the same heads ported by someone else pick up tons of power. Experience is a big player in this game. Keeping the most velocity and allowing the best flow is key. Bigger is not necessarily better, especially on a small displacement engine.

 

hopefully you'll get an M112K guy to port and see good results. keep us posted!

 

Healthy numbers – even from the stock ports. Dramatic improvements after your tweaks.
Was your data obtained at 28 inches of pressure differential?
After I:E flow ratio looks rather unusual IMHO. Of course, track times will ultimately tell the tale.

Good luck, Anthony.

www.tvtdes********

 

You are not alone on this one

After mods, have a ratio of about 0.65 I/E

EVERY head I have EVER used was closer to about .75

I would like to see REAL world data, aka ET/MPH before and after please