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I probably should have followed Rod's instructions, but.... Here are the pics of the porting i have done thus far-passenger side is finished. I got a little carried away! I used 2 inch pipe and plugged the open ends of the 2" pipe with the sections i had cut out off the front of the J-pipe. I think it looks like a grenade launcher.












[ June 21, 2007, 12:33 AM: Message edited by: Cobra-Stang ]
 

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Discussion Starter · #3 ·








I still need to clean up and get to some areas on the inside with my die grinder and carbide bits. I got a little too close for comfort to the bolt holes with some of my welds and that might end up being an issue.

[ June 21, 2007, 12:28 PM: Message edited by: Cobra-Stang ]
 

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So what effect do you guys think these will have on flow since the transition isn't gradual and smooth inside the j-pipe?? It's pretty smooth where it dumps into the sidepipe, but clearly not inside the j-pipe where it goes from the 2-1/2" pipe to the bored out section.
 

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Hard to say what the outcome will be. Don't think it will hurt? You moved the transition from small J pipe to large collector, similar to what would happen if shortening the J pipe or maybe exdending the collector. More low end?
Also think the exaust might get quieter.
 

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Discussion Starter · #7 ·
Only took me a couple of hours to fab up my pipes and they didnt cost me but 20.00 in 2" pipe sections. 165.00 isnt exactly cheap and i dont think i'm not sure that i could get the angle right-its not like you could just weld on the bolt plate to the front of that collector.
 

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I like Cobra-Stangs home made solution. Looks like the boosters on ballistic missiles.

I see a theme here...
 

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Any bets on hp gains?? I should have the other pipe finished up tomorrow and then i will try to get to the dyno on saturday or sunday.
 

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Why did you not just taper the pipe so it would be a smooth transition? You spend all those hours building the car and you take a 1/2 hour short cut on something so simple. Not bashing you, just acting like a dad. Aron
 

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Not sure-just got something up my sleeve and rolled with it. I have 3 sets of j-pipes so i figured i would go with whatever felt best at the time and then if it didnt work out i could always go back later and try the other method.

You really dont see this section of the j-pipes unless you bend over the fender well and look down so i wasnt worried about anybody seeing it. My car isnt a show car anyway. This was just for fun, not to really impress anybody, unless they pick up some hp.
The transition will be smooth in the end. I just need to go back with my die grinder and the welder and fix a few spots. Yes, it dumps into the main section and i cant fix that, but i figured it really wouldnt matter at higher rpm.
 

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Originally posted by cobrastang:
Any bets on hp gains?? I should have the other pipe finished up tomorrow and then i will try to get to the dyno on saturday or sunday.
Id estimate somewhere between -10 and 5

Looks to me like you added alot of turbulance and restriction and simply moved the point where it happens further down the line.

But A for effort!
 

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LOL CS! Reminds me of a dog with 3 tennis balls in his mouth for some reason.



Should still provide some benefit since it unshrouds the 4 pipes so it reduces restriction. Who knows, the aero effects and turbulence in the pipe may even serve to helps things out. Airflow in pipes is not easy to predict and can often have unexpected results. I would expect a 5 to 15 HP increase since the originals saw +10 HP in the Exhaust Shootout . Are you doing spikes as well



How To - Super Port Your J-Pipe!

Looking forward to the dyno results!

Cheers, Rod
 

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I'm going to do the aerospike after i go to the dyno and get the results on my grenade launchers
If the results are not favorable for my j-pipes then i will grab the set that is on the car currently and cut them up. Either that or i will yank the CC inserts out of the other pair i have lying around and do them.
I still have a lot of smooothing out to do on the inside of the j-pipes. HOwever, i am going to leave the slivers of metal that are inbetween the ported areas because it looks like it might help cut and direct the air towards the seperate tubs on the sidepipes.
 

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Made the dyno appt for this afternoon. Any more guesses on hp loss or gain??
BEFORE



AFTER


[ June 23, 2007, 03:07 PM: Message edited by: cobrastang ]
 

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Id be curious to see. I still dont get it though, to me it looke exactly the same except you moved the transition down the line 6" or so.
 

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Gained 1 whole rwhp. Not sure what the equates to in flywheel hp, but definately a waste of time. I lost torque between 2,000 and 3,500rpm.
The point was to unshroud the area where the j pipe meets the sidepipe. If you look at rods pictures it's obvious that this is a point that inhibits flow. His design worked, mine did not. Ok, so i am done playing with the exhaust now-time to move on to bigger things.
 

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I think you could improve yours by simply adding diagonals on the bottoms where it transitions. The way it is now the exhaust runs into a flat brick wall at the bottoms of those tubes. Id weld in some angles. You want it like a funnel going from the large to the small.
 
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