VMAX451

First off a disclaimer:
Different dynos, but both Dynojet 248C's, so if this means the results are completely bogus then disregard the rest of this...

Anyways, in case this is of interest to anyone, I recently swapped out my Hooker 2061-1 ceramic coated shorty headers for the new design Exotic Muscle long tube headers. There were no other changes. The results:
+14.8 rwhp, +15.6 rwtq

Pretty much what I expected. Torque was up consistently across the range.

Here are the charts:

New, with long tubes:



Previously with shorty's:



Unfortunately the dyno shop was unable to give me copy of the data files so I couldn't do a direct overlay, but here is a crude version from the raw data:



So are shorty's worthless? I don't know, I would have to swap the LT's with the stock manifolds and dyno again, which I am not going to do. But it appears that the LT's do perform noticeably better and do not cost much more.

For reference, the other mods are Corsa exhaust, 160 stat, Ed Wright custom prom, LPE 211 cam, and the usual free mods. Heads are stock but were cleaned up a little when I had them off one time.

Anyways just another data point for anyone considering going to long tubes. :seeya

vader86

:cheers: about what i expected

Drewdog

thanks for the info :thumbs:

Nathan Plemons

:cheers: Very good, thanks for the info. I'm glad that somebody finally took the time to do a comparison between shorties and long tubes.

Although it's a healthy gain on peak numbers they still don't tell the whole story. Notice how your torque only falls to 300 now where as it used to fall off to 250! That's a 50 pound of torque increase at that particular RPM. That's the sort of thing that peak numbers will never show.

One thing that is curious to me is how your torque curve still remained so smooth. I'm running a Hot Cam as you probably know and my power gains with headers were very impressive, but my gain came in the form of a larger power spike. Although I lost nothing on the low end I got a huge gain in mid - high RPM range. At about 3000 rpm's my graph jumps up about 40 pounds of torque. Maybe it's the different cam, maybe it's the x-pipe and flowmasters? Maybe it's Hooker Headers vs. Exotic Muscle.

In any case long tubes were the best seat of the pants thing I have done for my car and the dyno shows why. In any case it's clear that Long Tubes are better than shorties.

I'm with you, I won't say that shorties are COMPLETELY useless, but for the cost long tubes are the better value. The only reason I can see running shorties would be if you had to have a CARB number to pass emissions, in such a case you would want to get everything you could out of the system regardless of cost.

:cheers: :cheers:

VMAX451

Actually it may not be quite that big of a difference, it's easy to miss but if you look close you will see that the shorty dyno runs went to 6400 whereas the later dyno runs stop at 5900. (The tach ending at 6k apparently spooked the operator.) Still it is a consistent 15 ft-lbs across the board, nothing peaky in nature at all, at least in the range shown.

I too was curious about that, I remembered seeing the torque bump in yours when you originally added the LT's. I think there may be an explanation though. If you look at the shorty plot you can see a (small) bump at 3000 rpm. The new plots don't really start until a bit after that. If the operator started the dyno run earlier we probably would have seen what you were expecting.

I didn't really look over the data until I got home. If I was paying more attention I would have asked the operator to start lower and run it up to the rev limiter like the other time, would have had a little better data then. Oh well, live and learn :) .

HOWSER

What type of LT's are you running? Also, how long did they take to install? Any hang ups?

I'm wanting to go with some LT's for my 93 and I need someone with experience to give me the scoop.:yesnod:

Eric

Nathan Plemons

If you're talking to me, it didn't take long to install the headers. It really took longer to get the stock manifolds out of the way than it did to install the headers. They are Hooker 2151's which don't have any smog provisions at all. The only hangup is that you have to turn one of the motor mount bolts around but that isn't really bad.

Any good exhaust shop should be able to make your stock catback adapt back to the headers for less than $100.

HOWSER

Thanks. Are there any available that have the smog provisions?

Curveit

:thumbs: :cheers: Congrats!!! I'm sure thats a good bump-up from the stockers.

:chevy

bogus

Great results... and I had nothing to do with them... so there.

mackeyred96

:iagree: good stuff :cheers:

FoolCrzy

...And That thing SOUNDS GOOD!!!

pwrful c4

Vince,thanks for the info,it win my headder decision. :steering:

Dale1990

Hooker 2149

Coated with AIR and EGR

hngacurv

Good info and nice numbers. :cheers:

cprgmr

:cheers: I knew I made a good decision by getting TPiS longtubes! :)