Dennis Welch Headers - their view

[DerekJ]

Following the recent, interesting exchanges on the subject of headers under the post "Headers on e-bay" I contacted Dennis Welch to see what they had to say, and to clarify the twin/triple carb 'confusion' on their site.

Jeremy Welch responded with the following information.

"With reference to your e-mail of the 2nd May. I would not expect a bigger improvement on the twin carb set up than on the triple carb.

The answer to your final question is yes. Many years ago, we took a stock BJ8 and fitted our twin carb exhaust with no other modifications. We rolling road tested it before and after and we saw a 12 bhp increase. I do not know of a better bhp for buck equation.

Yours sincerely,

Jeremy Welch.

Place your orders!!!! /ubbthreads/images/graemlins/yesnod.gif

/ubbthreads/images/graemlins/cheers.gif

 

[Bruce Bowker]

Already have them installed.

Bruce

 

[Dave Russell]

I installed the DW Derrington style headers, muffler, & tail pipe on my BN2 several years ago. A lot of hot bending required to get the headers to fit to the head correctly. A combination of measuring & prebending to get things lined up & then reheating to stress relieve after they were bolted to the head. The intake & exhaust flanges required some work to exactly match them in thickness. The studs which secure both intake & exhaust flanges will NOT bend sideways to acommodate different flange thicknesses.

Maybe I just got a "bad" header. Wasn't about to send it back across the pond for another try.

Since this was done in conjunction with A DW aluminum head & several other modifications, it's hard to say how much the headers alone helped. There is no doubt that long primary tubes will help some. The overall combination works really well.
D

 

[Keoke]

HI Bruce ,did you get a 12 HP increase???---Keoke /ubbthreads/images/graemlins/smile.gif

 

[MotorHead67]

DerekJ,
What a great idea.
I'm glad you took the time to straighten that out. I'm also glad that, it seems, they've improved the fit of the headers.
I posed a picture of my motor before I installed it on Sunday. See the attached.

 

[Dave Russell]

MH,
It sure look great all nice & clean. Now ---------- If you can just keep it that way!!!
D

 

[DerekJ]

They look great dont they. BTW what do you guys think of the sound. Its different but is it better?

 

[MotorHead67]

DerekJ-
Can't comment on the sound yet. I hope to fire it up this weekend for the first time in more than a year.
You've mentioned that it changes the sound...I've got a full stainless steel exhaust (I know, counter-productive) so I expect it to be louder. Hope the 'rasp' is still there.