Back to back header testing 4xx inch LSx...
Back to back header testing 4xx inch LSx... We did some back to back testing on a NA setup, hyd roller between Kooks 1 7/8 inch 3" collector Kooks and their 1 7/8 stepped to 2" w/ 3.5 collectors. Figured the bigger collectors would kill a substantial bit of torque down low, especially since this motor has plenty of exhaust port/exh lobe
The stepped headers actually made about 10 ft lbs better torque from 6000-6800 rpm, above that the curves were pretty much identical. We didnt run extensions on the 1 7/8 headers because I wasnt worried to much about having too much header with them, but that would have probably made them about even everywhere.
Peak torque rpm was pretty much unaffected, and the bigger headers moved peak hp from 7300 to 7400 if I remember correctly. I think it was 505 vs 509 hp on our Mustang dyno, and the motor had only fallen of 13-14 hp at 8000 rpm. She pulls hard right into the limiter
Anyone have any midlength 1 7/8, thats what i really want to try
The stepped headers actually made about 10 ft lbs better torque from 6000-6800 rpm, above that the curves were pretty much identical. We didnt run extensions on the 1 7/8 headers because I wasnt worried to much about having too much header with them, but that would have probably made them about even everywhere.
Peak torque rpm was pretty much unaffected, and the bigger headers moved peak hp from 7300 to 7400 if I remember correctly. I think it was 505 vs 509 hp on our Mustang dyno, and the motor had only fallen of 13-14 hp at 8000 rpm. She pulls hard right into the limiter
Anyone have any midlength 1 7/8, thats what i really want to try 
can you post a graph? I just installed the same header on my car and im interested in how it looks down low. I went from the hooker 1 3/4 long tubes to the kooks 1 7/8 stepped to 2 w/ the 3.5 merge on a 4xx ci. lsx. So im sure i picked up alot over the hookers. thanks
Fbody, no worky! Theyd be detrimental to power in the 7-8K range I think with their long collectors
Yeah it rpms well for a steel valve hyd motor, well enough I forget I could only turn it 8K on stock PCM and smacked the limiter on the dyno once
GrannySShifting
Theyd be detrimental to power in the 7-8K range I think with their long collectorsYeah it rpms well for a steel valve hyd motor, well enough I forget I could only turn it 8K on stock PCM and smacked the limiter on the dyno once
GrannySShifting
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Originally Posted by AshWS6
Fbody, no worky! Theyd be detrimental to power in the 7-8K range I think with their long collectors
Yeah it rpms well for a steel valve hyd motor, well enough I forget I could only turn it 8K on stock PCM and smacked the limiter on the dyno once
Theyd be detrimental to power in the 7-8K range I think with their long collectorsYeah it rpms well for a steel valve hyd motor, well enough I forget I could only turn it 8K on stock PCM and smacked the limiter on the dyno once
I feel like a MORON. I didn't even notice the WS6. Duh, you are correct sir. Bobby told me awhile back that the Fbody version is in the works. I wonder what happened to them. I remember posting over a year ago, to be on the lookout for f-body LG Pro longtubes. Maybe they fizzled out. I will have to ask Bobby next time I talk to him.
