HP gains of THDP on my setup??

[DR. EVIL]

You can look at my current setup in my sig.

I just purchased a 3" THDP with the dump pipe. Now my exhaust is completely straight piped.

Say I'm running mid to low 12's in street trim and somewhere in the 11's on race gas, what kind of gains will I see in HP with the THDP?

My car hauls balls in the low end, but you can feel how choked it is in 3rd gear. It still pulls, but no where near as hard. I'm guessing I'll start noticing the benefits of that TA-51 turbo with the combo of the 3500 stall and the THDP Whatchu guys think??

 

[UNGN]

I saw .05/1.5 mph. Here's my test results:

Here's the numbers from the test performed at Buicks @ Bristol 2001. Everything else was equal except the elbow.

Ported elbow/2.5" ATR downpipe/testpipe:

11.840 @ 113.08
11.859 @ 114.66
11.836 @ 114.72

Average:

11.845 @ 114.15 (avg 60 ft 1.680)


Terry houston 3" DP/Capped dump pipe:

11.745 @ 115.36
11.788 @ 116.05
11.838 @ 115.62

Average:

11.790 @ 115.67 (avg 60 ft 1.687)

Difference = .055 seconds and 1.52 mph

The results surprised me. I thought the THDP would be worth more. These weren't even all the runs. If I factored in the others (made it an avg of 5 runs each) the stock elbow ET would be a little closer (though the mph would stay about the same).

You can't knock a 1.5 mph increase, but it appears to help the top end charge more than the ET. The rest of the combo is stock driveline, stock intercooler with a neck, bluetops, TA49, 275/60 BFG's weather was in the mid 60's, track elevation 1400 ft or so. Your results may vary.

 

[DR. EVIL]

Well, I'm guessing I'll see more than 1.5mph. I still have an unported stock elbow and the stock 2 1/4" downpipe! I'd probably see 1.5mph just outta porting that elbow and the 2.5" downpipe, let alone the 3" THDP! I don't know......

 

[azgn]

to pinpoint specific gain would be very difficult...you'll find out when you go to the track....too much is dependent on the rest of your combo...for example, your major restriction is now on the other side of the turbo i.e. the stock intercooler

something like the TH downpipe will only enhance other improvements in your combo and will be optimal into power levels well beyond what a stock block will tolerate

 

[DR. EVIL]

This is very true....next will be a frontmount..... CAS V2 possibly? I've heard some good things about them....

I'm only asking here because since I've been at the track last I've added the Trans+ w/ extender chip and 3" MAF, 9X11 converter and "Killer Street" tranny from Performance trannies, and now the THDP. So much has changed that it would be impossible to know what gave me what gains.... Circumstances came into play and I almost had to do everything at once....long story.

At any rate... most everything I've read estimates 25-35hp.

 

[BlackBuickBeast]

I'd say you will get 2-3mph atleast going from stock to THDP. Against what most people here say, I noticed a big difference from stock. I order a THDP and 2-1/2" exhaust and the downpipe made a bigger diffence than the exhaust(got the downpipe in the mail first). I went from a car and a half back on my friends vr4 to a car in front with downpipe alone, dump capped and with the cat. If you don't want to mess with porting out your elbow and also have the cash THDP is the next mod you should do.

Oh, and also it made a huge diffence in 3rd. 3rd will just keep on pulling.