Header question. Please "steep" in......


I will try to explain this the best I can.....

This thread is about headers for my car, or headers in general (421 cid). The combo now has a set of AFR 195cc Comp Ports, and I will be changing heads in the spring to a set of 220cc Comp Ports which IMO, and the opinion of a few others is a much better head which will optimize my combination. When the engine was built the 220`s were not out. But in saying all that the motor does make great power with the smaller ports, and the low end, and mid range is awesome and thats with 3.07's, lol.

Six years ago or so I bought the Hooker 2149's which are 1 3/4 primary. Many on this site have these headers and are probably the most sold header for the C4 L-98's ever. The funny is that I knew this were too big for the stock L-98, but I had plans in the future for bigger cubes so I had a good idea that I would grow into them sort to speak. Now in saying that the car picked up about 3 mph in the 1/4 mile with the headers and dual exhaust.

Lately a straight up forum member has put his Stahl headers up for sale which are 1 3/4-1 7/8, and I said that I was interested but was concerned about the fitment. After speaking to a few friends, they are say that I will pick up horsepower in the ballpark of 20-25 hp, but I have searched the forums that count and there is little to no evidence that stepped headers would gain me anything.

Alot of us know the name Joe Sherman. He has been around since before I was born, and it seems like he has a wealth of experience. Joe claims that a 1 3/4 header can support up to 600 hp.

I feel bad if I dont buy these headers, but in saying that there seems to be a line-up. I was of the opinion that I am running enough cubes to support the Stahl stepped headers or the ARH stepped headers, but not so sure anymore. If I was sure to gain say 20-30 hp then I would probably buy them if fitment works, but if I am looking at gaining "0" or single digits, then it makes no sense what so ever! I have a feeling that gains in headers, and primary tube have something to do with gains so I will have to state that with the 220's, I am looking at peaking around 6100, and shifting around 6300-6400. I am coming to this conclusion because the 195's comp ports peaked at around 5800, and I shifted at around 6100.

I know Willie gained power with the stepped ARH's, but I believe his peak is much higher then mine. Maybe he will chime in.....There has been some other guys on here with strokers with the ARH's, but none have any proof of any gains.

I guess I should come up with a question.

Do you guys think I would gain power, or is it somewhat a waste of money? I personally think I will gain a little because the Stahl are a better made header, and I think have longer primarys.

But who is to say? I have other things budgeted for the car, and I want to spend my money wisely.

Sorry for the rant, lol!





Thanks guys.

 

......... If you are running through an exhaust system ... including mufflers ... you likely won't see a dramatic difference ... Jere Stahl told me that 1 3/4" headers were adequate to 700hp naturally aspirated ..... he sells race headers and street headers for the C4s ... there is a difference .....

 

Joe says they are good for 700 Id say youre fine.

 

Coming from someone who has done his share of internet searching on the matter, I too have seen the 700 hp mark as the ceiling of the 1-3/4'' header. That's across many forums, can't be coincidence. Not sure how that would work out with a FI application though.... Rick....you are really thinking long term with this one.

 

I will agree with c409,with a full exhaust the gain may not be what you hoped for.I have had stahl headers and found them to be the best for fitment and power on an open header drag car,but a full exhaust is the big equalizer.I would love to try stepped headers on my 427 and i to run the hookers on mine.Like to hear what you find if you get them..good luck

 

Hi Rick. Just saw your post. I agree with others; the downstream exhaust in a way diffuses the header type decision you are making. If you are running open exhaust or a race setup, I would think with your cubes, the stepped headers would work well, especially if you are contemplating future upgrades. The difference between the Hooker 1 3/4 and the ARH stepped headers was significant in my case (a tenth or tenth and a half). I run an open y pipe which I feel increases torque over open headers. If that was bottled up with a full exhaust system, the gains would be diminished. However, even with a muffler setup, I think you will still see some gains. I think I've just made a whole circle here. Willie

 

Ok thanks for the replys guys.

It seems that having a full exhaust system which I do have will hamper results.

Willie, I agree that I will gain HP and TQ, but how much is the question? I'd need to gain 20-30 to make it reasonable. 5-7 hp or so wouldnt cut it!

I am getting the feeling that the $1000 for upgrading headers will be better served into suspension and brakes.

I was knee deep into getting something, and pretty excited, but the doubts are certainly setting in.

 

Rick, you know if you don't go the stepped header route, you will always wonder what could have been and regret not doing it.

 

I've run TPIS 1 3/4 and now ARH 1 3/4-1 7/8 stepped headers. I have no dyno numbers for comparison, both work well. Seat of the pants at the track says they are close maybe a little edge to the stepped ARH's as expected from the mid range to the top end with my combination. If there was a chassis dyno close I would have liked to do a comparison but nothing close to where I live so just subjective results.

TPIS headers are little better fit, use the stock bolts at the heads and are easier to install because of this. Also with my adapter for a remote oil cooler the oil filter would not clear the AHR headers so I had to go to a remote filter mount. This probably would not be an issue if you do not have a remote oil cooler adapter. After 10 to 12 years the TPIS coated headers had to be re-coated once and finally the coating was going bad again and some of the welds and tubes had cracked at the collector so I changed headers. The ARH SS headers are a nice piece just a little more work to install.

 

.............. As I recall , the Stahl headers have a 3 1/2" collector vs the 3" on the Hookers ........

 

sell me your 195's so you can get on with going "Ludicrous Speed"

 

I have a buyer for them I believe. If it falls threw I will let you know.

 

I understand your point, but I dont want to waste $1000. If it was cheaper then that then I wouldnt be bummed out if I didnt notice good gains.

It seems with full exhaust that good gains wont be seen.

 

This question is hard to answer without all of your specifications and goals but don't let the full exhaust comment fool you. A well designed full exhaust system can be made to work fine with headers and if it is working correctly you will notice a difference. At 600 HP a stepped 1-3/4 to 1-7/8 header offers potential Hp gains over 1-3/4 headers. Make sure your exhaust backpressure is low (1 PSI or less) and they will perform.

 

I am no end all to anything regarding this but the majority of my vehicles I have put headers on.

One thing that many tuners have told me and my experience with others as well is that yes, the smaller inner tube headers will support 600+ hp....but in saying that you still leave some HP on the table by not going to the larger set.

So say you make 600 hp with the smaller set.....yes, they support 600 hp. You still can and will make more with the larger headers. Guys have this issue all the time with their LS3s. They go with the smaller set up and it works great and they make 600+. But just because those headers support it doesnt mean they work as well as another set with larger primarys. Just my .02.

If the OP wants to sell his headers he should pm me....hahah

 

I understand what you are saying....I am torn. Argh!!

 

Hi Rick

I am glad it's you trying to decide and not me. Have you decided to not install any cats and run with the 3 inch exhaust you have now. If so I am not too sure you will see the kind of increase you are after. When I went to the 220 AFR heads and the full 3 inch full race cats and 3 inch s/s pipes to 3 inch flowmaster delta flow 40 mufflers, I had a fair{by seat of the pants} boost in power. You have the bug and I know what it's like, all you can do is get all the info you can.

Good luck
Brian

 

JUST DRIVE IT sheesh Ricky