I have been debating if I should install headers on my 01 GT with auto trans. I was told that the factory manifolds work fine for engines producing up to 400 horsepower and that unless you install a blower or turbo there is no need to upgrade with the few simple bolt on's that I have ( TUNER,FLOWMASTER 40'S,BBK 75MM TB, C L INTAKE, PULLEYS AND 3.73 GEARS) I will be installing a pro chamber X pipe and 4.10 gears soon. IF I install headers I have been debating on equal length bbk shortys or going long tubes with shorter X pipe. I realize that they are a P.I.T.A. to install. wich is harder to install,long tubes or shortys? or do I leave stock manifolds on. I'm tired of getting beat by my friends STOCK 2002 TRANS-AM at the track.

 

There is no difference between installing shorties vs. long tubes. Long tubes should knock 2 tenths off your quarter time. Whoever told you the factory manifolds are good to 400 hp was wrong. You ever look at a set?

 

I was leaning towards the BBk equal length shortys due to the fact the factory H pipe with cats could be reinstalled if neededand they cost about 100 dollars less than the full length. I'M not sure how much difference there is in horsepower gained with long tubes over the equal length shortys?

 

actually theyre good for more than that...heres a 500 rwhp car with stock manifolds....
http://www.modularpowerhouse.com/for...p?do=view&id=2

 

and if you take off those manifolds it will gain assloads of power. the point is he was told they dont hurt performance till or that it wont help till 400hp thats flat out wrong even on stock motor you can gain hp from a good offroad mid pipe and long tube header.

 

Well, dont expect to beat your buddys stock TA with headers, to beat the LS1's with our cars, it takes a lot of skill and you have to have the horsepower to do it with. Maybe you should work on your driving skill, or instead of headers, buy a new differential and new axles to go with the 4.10's. That way, you can run slicks and cut good 60 foot times to try and make him play catch up. If you just keep adding power, you just spin the tires. Also maybe get some lower control arms to help you hook. Youd be amazed what some simple and somewhat cheap suspension work will do for you. But if you really are set on headers, get the longtubes and be done with it. The shorties are supposedly a lot of work for marginal gains. If it were me, Id do the suspension and rear end first, do it while you have the pumpkin open in the first place, and be done with it. Good luck,

 

I could not have said it better myself. :headbang:

 

Another thing your could try is a good set of full length subframe connectors, these really help to stiffen convertibles. GT convertibles are notorious for flex, and flex chews up power. If you are serious about racing that rag top I would stiffen that chassis as much as possible. I see you are from MN. what track do you run at, I went several times to BIR last summer for Wed. night street drags. I heard there was a Dragstrip operating near the Twin Cities, is that true??

 

Also, if you drag race a lot, you should get the Subframe connectors no matter what. All that launching with twist the frame pretty badly. They are kinda something everyone should do.

 

I ran at Rock FALLS RACEWAY near EAU CLAIRE WISCONSIN. At the time the only thing done to the car was 3.73 gears,generic cold air intake, welded in flowmasters,hyper-tech tuner. I ran 14.4 twice and 14.5 once and 94-95 mph in quarter. I think with adjusting shift points my best would be 14.3? The car ran strong and with 28psi in the stock eagles with a short dry burn out I hooked up well. I havn't heard of any new strips near metro,there is a 1/8 mile called grove creek w of metro

 

I didn't know that B.I.R. had much for amateur racing events other than show and go. My parents live 15 miles north of the track and my hours are flexible enough to attend some events up there if I can get a schedule. I have drag raced cars and bikes on the track several times but only took this mustang once last fall. I intend to put on a few more bolt on's but I dont want to install a roll bar wich is required with converts that break 14 seconds

 

when i had my x pipe put on there was a 99+ gt on the dyno that made 14 hp to the wheels with shorty headers n/a. but i dont know what else was done to the car. but definitly no sc.

 

Those are some pretty good times for a vert with an auto! I might have to try Rock Falls next summer. The track at BIR is fun but I would like to try other places. It seems i get better traction on the street on the stock Goodyears than i can get at BIR :angry1: They have had street drags at BIR for several years, usually twice a month from May thru Sept. There is a good mix of different cars there from classic Muscle to Ricers.

 

I like the BBK equal length shorties for exactly the reasons you listed. They will free up power in the upper rpm's, where you live while racing. They also allow you to re-use the rest of your factory exhaust, then you can add a good X pipe later on when funds allow.

Also when I said that the factory units were good up to 400 hp, I meant they still cost you power. Any header will get you power over the factory units. You can make 400+ through the factory units, but the same motor would make more with headers.

 

If people think you can make good power thru the stock exhaust manifolds...well heck, I got set right here that i suppose I could part with . One thing you need to look at is the size and weight of the stockers. Kind of like an O/R x-pipe compared to a stock H. Will it flow better...yes....will it make more power....yes....but it weighs nothing compared to teh stock H. My FRPP shorties don't weigh hardly anything compared to my stock manifolds..I should have weighed them before i put them on. DOH! My shorties make alot more power up top...where my cams make power. They might not work as well on a car that only sees 5900rpm. Good luck with whatever you go with...anything is better than the stockers.

Adam

 

I have seen ads for the ford racing shorty headers and they are priced very reasonable. Although they may not make as much power as long tubes or equal length shortys they should outperform stock manifolds at upper rpm levels. I'm guessing that they may have more clearance and be easier to install then the BBK equal length shortys?

 

There have been some people that have had issues with the FRPP's cracking on the flange....I haven't had any problems though. I bought mine because I got them used for like $100.

Adam

 

I have heard to stay away from Mac, True?

 

Mac rust out fast, but they are cheap and make good power. It all depends on how much you want to spend. The SLP's they sell on this site are about the best quality along with Hooker's that you can get.