Advantages of 2.5 exhaust over 2 1/4?

[FromaBuick6]

Guys,
If I'm running a 2 1/4" exhaust with generic turbo mufflers is there a big advantage to going to the Hooker 2.5" catback system? The 2 1/4" pipes are NOT mandrel bent they are compression bent, the Hooker 2.5" system IS mandrel bent. Sorry, I know plenty of people who endorse the ATR systems, but I can't afford it. I'd like to know though, if there is a decent amount of horsepower to gain by going to the 2.5" system? What do you guys think? - FAB6

 

[mycarsucks]

Do you have any information on your car other than what is in your sig? Dyno/Track times? It's hard to tell what the limiting factor of a combo is without knowing the combo or at least the performance. These TR's are pretty funky cars, and there are alot of people with parts for the 9s that run 13s.

 

[FromaBuick6]

OK

Here's a little more detail:

PT-52
Thunder Fab IC
PAC Alky
CAS FPR
Walbro 340
Delphi 50# injectors
3"THDP
Mystery mufflers ??
T-Plus w/ Extender
10" 2800 stall L-U
Power Plate
BFG 275-50-15 DR's
Fully boxed rear end w/ bags

I've run a 12.70 @ 106. That was with a 2 lb boost launch. That's all the boost I can hold on the line. I do believe that run was with 24 lbs of boost, and the extender on the "98" octane setting which is about 21 degrees I think. In my opinion the car should be running faster than it is, so that's why I'm looking at the exhaust system. - FAB6

 

[mycarsucks]

I don't know how economical a solution is for you, but have you considered a dump? I assume that you or an exhaust shop could fab one up for pretty cheap with no cap or anything that would allow you to bypass your exhaust just to test. Theory is good, but I would think that would tell you as a sure thing.

What do you think?

 

[FromaBuick6]

Well

Actually I do have a dump, I hadn't really thought about that. Maybe that would be worth a try. - FAB6

 

[JToups386]

The open dump pipe is worth at least 1.5 tenths, and 1-2 mph in the 1/4 mile! If you have it, use it at the track!

As for your exhaust question, consider this --- A motor is merely a big air pump. The more air in, and the more air out, as efficiently as possible. If you're running the stock exhaust w/ some sort of "mystery muffler", then in all likelihood you are hindering the outward flow. I don't think you need to have 3" to run the absolute best, as I've had 3" w/ Flowmasters that did not perform as well as my current Hooker system overall. Of course, Flowmasters are NOT good turbo application mufflers.

I bought the Hooker catback system w/ their Aerochamber muffs, and I am thoroughly pleased with it. I truly believe it's the best system for the money! Yes, you can get a better system from ATR and others, however, they'll cost double the money, and will not offer any gain over the Hooker, IF, you are running an open dump.

The Hooker system was extremely easy to install, with no welding. It came with all necessary hardware, it fit properly, and it sounds very unique. I am sold on it!

So, if you've got $300, you can get a nice street system, and then just open up the dump when at the track. I ran 12-teens through the Hooker system.

And, in looking at your combo, you should be approximately 7 tenths to a full second quicker, with the right conditions. Sounds like you've got some tuning to work through as well.

 

[87gninpa]

I had that same crappy 2 1/4 exhaust on my car and just put on the hooker system and i definately noticed a bit more powere when just cruisin around town, especially on the initial spoolup. its definately worth the $290 and it fits like a glove

 

[charlloots]

i dont believe there are any performance gains with a dual atr over dual hooker the onlt difference is atr is stainless and hooker is aluminized steel the atr will last longer

 

[klrv6]

Part#

What is the part number for the Hooker kit with the Aerochambers and where were they purchased? Thanks

 

[87gninpa]

Just go to summitracing.com and for keyword type in grand national. under hooker will be the cat back system. i have it on my car and absolutely love it