[quote=futuresvt;5529453]I'm understanding your post to mean the only brands were Kooks or ARH. I am pretty much limited to ARH because I want an H-pipe rumble and want to stay street legal at the moment. I also understand they are high quality.

Kooks does make a catted H-pipe now, I got mine from Brenspeed

 

is there an advantage to 1 3/4? either blown or N/A? Seems like most have 1 3/4...

 

Just general observation, 1-5/8 headers gnerally seem to crap out around 350-400hp and 1-3/4 headers generally seem to work in the area of 375 to just above 500 in naturally aspirated engines.

If you dig enough, you can find info on how to determine best header configuration (the more accurate ones use cam timing)

 

I went with ARH 1 5/8" since I have NO plans for F/I. Could definitely feel a difference when they were 1st installed and now, after CR did a custom dyno tune, the car is a BEAST NOW!! Gained almost 50 hp to the flywheel. Best of all, NO CEL's, and I am fully street legal and emissions legal!!!

 

I have guys running 1 5/8" Kooks offroad at over 600RWHP. Kooks also does have an H Pipe available now, and it's pretty cool. The 1 3/4" headers will not have a loss, just not as much of a gain. Once you can force some air through them (ie. heads, cams, nitrous, turbo, supercharger) you'll see a large difference in the 1 3/4" over the 1 5/8".

I personally would run the Kooks w/H Pipe and 1 5/8". Even with the S/C it will be sufficient. Ask JDM in Jersey, who run those headers on Saleen SC cars with sick RWHP numbers.

CR
Tillman Speed
610-497-5776

 

I will still say that a 1 3/4 header will not adversely affect a NA car, whether it be a + or - change. More power potential is there on a blown car with 1 3/4 system, however on a NA car I don't believe you'll see any difference. Anyone with before/after dyno charts and/or drag ETs with evidence to the contrary, please post them up.

As far as tuning any other system besides American Racing or Kooks, I won't touch that subject other than to say that there are lots of tuners that have tuned many different brands of headers other than those two, all without driveability problems or issues with the O2 sensors heating up properly and on time.

 

I can probably pull up some dyno charts for you. I'll have to find ones where the accompanying mods are as close as possible. I can tell you one right now where the guys pushing 307 and probably on 1 5/8" would be 315 or so. Torque-wise the number was 322, and probably would have gained a little there. Once he decides to do the charger, his numbers will be much better than if he had gone with 1 5/8". As stated before, there was no HP/TQ LOSS just not as much of a gain. We're also talking about approximately 7 HP here, which can be made up with other modifications to throttle response, etc.

Now as far as tuning goes... Yes, you can tune other brands without a problem. We just notice that the upstream o2's tend to take longer to warm up with thin-wall headers than with something comp. with a Kooks or ARH stainless thick-gauge setup. Ceramic coating always helps, though.

It's not to say that you're not getting fuel trim readings, or driveability problems. There are plenty of variables that can be modified to fix it. O2 transport delays, temp to turn on, etc. I'm just stating that the reason you pay an extra couple hundred dollars is for thicker flanges, thick wall T304 stainless steel. I won't mention any names, but with the two above mentioned brands, the install is so much cleaner, and clearances are 20 times better. We've installed them all, and I know which ones **** off our techs and which ones they're happy with. Hooker headers for any mustang 96 and up are just about useless. They're two pieces, and need to be heated up, hammered, cut and re welded, kicked, screamed at, and finally they'll barely fit. This is all after the motor is pulled atleast two or three times. And then you get to replace them within a year or so because they're already corroded. Call them "semi-universal". The list goes on and on.

Point blank, I'm the kind of guy that wants to do it once... the right way. Not being biased, I am a dealer for OBX and JBA. I'll sell a customer whatever they want. I will tell you when you can get a better product, and just leave the option out there. If they're happy with a different brand, awesome. If not, I'm not going to say "I told you so." Find someone unhappy with American Racing Headers or Kooks. Then search the internet for the competing brands beefs.

CR
Tillman Speed
610-497-5776

 

Tillman- my comments weren't directed at you specifically......... but since you mentioned that you're a dealer for both OBX and JBA, why don't you post some graphs of those two systems head-to-head? I think you were asked to do so a few months ago in a different thread, but I don't recall seeing the numbers. Sure would be interesting to see.

Also I went to your website- the "Speed Shop" section links you to APD Performance and references your info. What is the relationship between APD and Tillman? I'm curious because the APD site only lists Mac headers for sale, not OBX, JBA, AR, or Kooks...??

 

I'm just another guy running 1 3/4" American Racing LTs on a N/A motor. I haven't had any issues. They sound GREAT, and fit like Ford designed them from the beginning. Now emissions and CELs are a seperate issue. Still working out the bugs on those.

 

No problem, I didn't think they were. We just haven't had anyone come in and really want to get the OBX or JBA's done in conjunction with a dyno tune or anything. We always have the Kooks and ARH on the shelf, and install/sell/support those more. Like I said, if someone comes in and wants it done, we'll do it and I'll be sure to post some graphs, the situation just hasn't occurred yet.

The APD Performance side is actually closing down. We've decided to just make our online retail part of Tillman Speed, Inc. We're in the process of opening a new online store right now! shhh

 

Ah, OK got it.... thanks.

 

Is there any truth to the alleged loss of torque due to alleged lower back pressure?!

I guess that's 2 questions. 1) Would there be a loss of back pressure? and 2) would that result in a loss of torque as a result?

If so I would think that everyone taking out cats and mufflers (SLPs!) would be having this problem...and I would consider that a problem because the torque is the best part of this car, and actually one of the reasons I want an H-pipe in lieu of a X (plus they sound better)...

thanks for all the replies folks