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Old 02-27-2010, 10:02 PM   #1
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Default How much was this costing me....?

Crawled under the car again today to take out a custom piece of pipe that I wanted to replace. Found out it was smaller diameter than I could have imagined...

Think this was hurting my spool and top end?



This adapts up to the downpipe.




I bet the exhaust shop was laughing when they made this....




So what now? I had planned on making a 3 inch pipe, perhaps with a dump, but since the rest of my exhaust is a 2.5 inch Enthuza with a Magnaflow I was thinking about just using this collector to go to a 2.5 inch pipe and call it done. The collector would be a better transition than a 3 inch pipe meeting a 2.5 inch flange.

Any idea what kind of spool gain down low and HP loss I was experiencing? I'm sure the VE tables will be all screwed up so it's a good thing the first race isn't this weekend.

I tried to eyeball my turbo inlet and it looked like 2.25 on the caliper (could not reach in there far enough) Does that seem like the correct inlet for a T04E 50 trim? I'm not going to take it apart right now to see what trim or AR it is.

Thanks!
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Old 03-01-2010, 12:30 AM   #2
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Ok I threw together a pipe with spare parts we had laying around. It's not real pretty but it should get the job done. I had a really hard time getting the stainless flex to weld without burning through with our MIG. It is really thin and just gets too hot. All of it had to be done with spots, could not run a bead.

So this new pipe cost me nothing but time and a little borrowed gas and wire. 3 inch collector to 2.5 inch to match the rest of the exhaust. Previously there was no flex from the downpipe. I still need to add a brace on the bellhousing for the downpipe.

If I figured correctly going from 1.875" pipe to 2.5" should almost double area of the pipe. I'll have to run VE Live this weekend on the way to STL. May have to adjust my wastegate again.

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Old 03-01-2010, 09:54 AM   #3
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in for huge gains. I had a 2.5" gasket in a 3" pipe (oops) and picked-up 200rpm earlier spool and much more power on the butt dyno.
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Old 03-01-2010, 10:06 AM   #4
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I am on the stock exhaust right now cause it has a cat on it (need to pass emissions / inspection)... I dynoed the week before i swapped at 206 rwhp. I bet you I am 30 hp or more down from that (granted i never retuned for stock so im running 10.5:1 afr . My normal setup is a fm 2.5 downpipe 3" testpipe and 3" enthuza.

I bet you that little pipe was holding you back bigtime.
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Old 03-01-2010, 10:24 AM   #5
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You will hear and feel a difference from this.

Not pretty, but nobody will see it.
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Old 03-01-2010, 12:30 PM   #6
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I've got an ebay TO4E .68 AR hot side I can measure if it's identical to yours. Mine's top mount v-band so its easy to get to. Let me know.
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Old 03-01-2010, 02:37 PM   #7
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Quote:
Originally Posted by rweatherford View Post

Think this was hurting my spool and top end?


No. Turbo's love plenty of back pressure!
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Old 03-01-2010, 08:28 PM   #8
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Quote:
Originally Posted by cueball1 View Post
No. Turbo's love plenty of back pressure!
LOL! I won't say how many times I've had the entire backpressure thread even on NA powered forums. Some things just never die.
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