Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: IrishCJ6 on July 13, 2011, 08:48:53 PM

Title: Header clearance issues
Post by: IrishCJ6 on July 13, 2011, 08:48:53 PM
Ok so I've just installed my new Hedman headers and I have a couple of clearance issues,

The LHS is basically sitting on the frame rail and the RHS is clashing with the rear spring mount bolt. I think I can remedy the RHS one by either shortening the bolt or reversing it. The LHS is a little more difficult, was thinking of cutting and boxing a section of the frame rail, any other ideas

LHS

(https://birtydastards.com/frm/proxy.php?request=http%3A%2F%2Fi274.photobucket.com%2Falbums%2Fjj254%2Fandrewspalding%2FDSCF0149Large.jpg&hash=9a122d04631f76dd2cffa681649ce68ecbd560fb)

RHS

(https://birtydastards.com/frm/proxy.php?request=http%3A%2F%2Fi274.photobucket.com%2Falbums%2Fjj254%2Fandrewspalding%2FDSCF0148Large.jpg&hash=fd44cf5f26030f829c2e3b087e464f5962a6883b)
Title: Re: Header clearance issues
Post by: Bulldog67 on July 13, 2011, 09:57:19 PM
they definately the wrong ones, they be FSJ headers  >:D
Title: Re: Header clearance issues
Post by: Dave The Sparky on July 13, 2011, 11:16:55 PM
That could be interesting with all the movement in the engine mounts and the ridiculously flexible chassis its all bolted to as well :icon_eek:
Just a thought but have you got the proper cj mounts for the engine?
Title: Re: Header clearance issues
Post by: IrishCJ6 on July 14, 2011, 08:19:20 AM
Yes they are the proper CJ engine mounts, yes they are the CJ headers as well
Title: Re: Header clearance issues
Post by: wildwood on July 14, 2011, 11:08:52 AM
1" raised engine mnts .........quite common on YJs and TJs to get drive shaft angle correct...........

Might work in your situation :icon_twisted:
Title: Re: Header clearance issues
Post by: IrishCJ6 on July 14, 2011, 12:08:45 PM
1" raised engine mnts .........quite common on YJs and TJs to get drive shaft angle correct...........

Might work in your situation :icon_twisted:

Yeah thats what the guys in the US reckon as well (apart from those that say to just bend the tube with a hammer) trying to figure out which part of the mount to raise, the one at the block or the one at the frame?
Title: Re: Header clearance issues
Post by: Nosebolt on July 14, 2011, 12:19:34 PM
what ever you raise make sure you raise it vertically while in situ, extending them linearly will reduce the width between the landing faces.

having seen your skills recon you could easily fabricate new chassis side mount brackets that would do the job
Title: Re: Header clearance issues
Post by: IrishCJ6 on July 14, 2011, 12:53:22 PM
Thanks for the compliments, yeah I think it will be a frame sid mod, now to figure out how
Title: Re: Header clearance issues
Post by: eastryjeep on July 14, 2011, 12:57:01 PM
Send the photos to Headman and ask for their suggestions with the thinly veiled query of WTF is wrong here?
Title: Re: Header clearance issues
Post by: IrishCJ6 on July 14, 2011, 02:11:02 PM
Send the photos to Headman and ask for their suggestions with the thinly veiled query of WTF is wrong here?

Good idea, have just sent off an email, lets see what comes back :banghead:
Title: Re: Header clearance issues
Post by: IrishCJ6 on July 14, 2011, 05:05:16 PM
Well look what the guys came back with - so called Technical support :hysterical:

"Andrew,

These issues that you are having are very minor. The hedders are made to be a direct fit but please take in mind 36 years of use and I’m sure some abuse, the variances in the chassis and the hedders. If you combined all of them you can run into small issues. The good thing is there are ways to correct them.

 

Are the motor mounts new or in good condition? Is the transmission mount new? Are they stock heads on the motor? "

"I thought the motor mounts in the photo looked new. So you will need to dimple the hedders where the clearance issues are. Use a small socket and hammer to dimple these areas. A couple light taps and you should have plenty of clearance."

What a joke, imagine if you were told the same thing when your car came backfrom the panel beaters and the door didn't close



 

Title: Re: Header clearance issues
Post by: ferretjuggler on July 14, 2011, 05:14:23 PM
Send the fuckers back. :banghead:

Quote the sale of goods act and call Trading Standards if they give you any shit.

Now you know why Hedman pipes are cheap :greggmo:
Title: Re: Header clearance issues
Post by: bigjeepzj on July 14, 2011, 07:53:27 PM
bunch of akers  :jump_125: :jump_125:
Title: Re: Header clearance issues
Post by: wildwood on July 14, 2011, 08:00:05 PM
I'm shocked :jpshakehead:

1" lift to the mounts then.........

Lift at the chassis as less compound angle bollix to suss out...... Good luck :icon_twisted:
Title: Re: Header clearance issues
Post by: Dave69 on July 14, 2011, 08:05:23 PM
personally i wouldn't dimple the headers, i have seen oval downpipes to cure clearence issues but making round into oval is not nessesary an easy option.

if you want to take the header route mark the area remove the header and slowly squash the header in a press just enough to give adequate clearance, unfortunately this is a one way fix for the situation

or

mark the chassis rail where they foul and then with your cutting and welding skills scallop the area to give clearance. take into account sideways rotation and forward aft potential movement to gauge how much to remove. Add an additional brace to the top and underside around the scalloped area to boost the strength back.

Title: Re: Header clearance issues
Post by: IrishCJ6 on July 14, 2011, 08:19:14 PM
personally i wouldn't dimple the headers, i have seen oval downpipes to cure clearence issues but making round into oval is not nessesary an easy option.

if you want to take the header route mark the area remove the header and slowly squash the header in a press just enough to give adequate clearance, unfortunately this is a one way fix for the situation

or

mark the chassis rail where they foul and then with your cutting and welding skills scallop the area to give clearance. take into account sideways rotation and forward aft potential movement to gauge how much to remove. Add an additional brace to the top and underside around the scalloped area to boost the strength back.



Dave,

That was my initial thought but when I suggested that on the US site they said I would induce cracking into the chassis and have a potential weak point, I can't see why neatly cutting the chassis rail and fitting a heavy box section in its place them seam weld it back together would cause an issue, even adding in a fishplate on either side for added security..

I had another thought also, what about heating up all 4 pipes at the plate end and gently bend the headers inwards, enough just to give clearance and allow for sideways movement?

No point in sending them back as it would cost me more in postage than the pipes are worth themselves.
Title: Re: Header clearance issues
Post by: dieselj20 on July 14, 2011, 08:20:30 PM
had the same problem with the advance adapters headers on my cj3a used a porter power to push the tubes about they move really easily just bolted them the heads tweaked them to suit

Title: Re: Header clearance issues
Post by: Nosebolt on July 14, 2011, 08:25:30 PM
I got second hand Headman fender wells on mine and one side was a bit distorted from a being on a crashed car, my fix was to V cut with an angle grinder the under side where the pipes joined the flange and then to close the gap and weld, effectively tucking the pipes in a bit.

not sure I would want to do that to a new set, in your case i would go with custom fabricated chassis side engine mounts as they are bolt on and the mod can be easily undone if needed.
Title: Re: Header clearance issues
Post by: eastryjeep on July 15, 2011, 11:00:12 AM
What about cutting a simple slit in the bottom of the pipes themselves, just outboard of the production welds, up close to the flange plate where the headers bolt to the head?
Gently tweak the bottom outlet of the headers inwards to where you want it, carefully remove the headers from the vehicle and re-weld the pipes. This way you won't loose much of the pipe cross-section, you can dress the weld smooth inside the pipes with a dremmel again and gas flow won't have been compromised.
Then just for the belt and braces approach you can reinforce your chassis rails to take the extra torque the headers should give. Don't forget to use a diamond shaped plate on the chassis sidewalls as ending the reinforcment with a vertical weld will induce a stress riser and is effectivly asking for trouble big style.
Title: Re: Header clearance issues
Post by: IrishCJ6 on July 15, 2011, 08:26:35 PM
So I think I solved the problem, on closer inspection today I found that the engine was lying slightly backwards, by jacking up the transfer box I was able to get clear of the clashes, so I fabriacted up a new rear transmission mount and for added security I took a little scallop out of the top rail of the frame, there was a slight over hang between it and the fillet section.

(https://birtydastards.com/frm/proxy.php?request=http%3A%2F%2Fi274.photobucket.com%2Falbums%2Fjj254%2Fandrewspalding%2FDSCF0151Large.jpg&hash=3559f3d36f5724a8fa36dd212a4fc92ffed7cded)

(https://birtydastards.com/frm/proxy.php?request=http%3A%2F%2Fi274.photobucket.com%2Falbums%2Fjj254%2Fandrewspalding%2FDSCF0150Large.jpg&hash=5d0e50eba300d07eb0bdc2721162548c1438cec0)
Title: Re: Header clearance issues
Post by: bigjeepzj on July 15, 2011, 10:03:38 PM
nicely done
Title: Re: Header clearance issues
Post by: willo on July 15, 2011, 10:20:56 PM


What a joke, imagine if you were told the same thing when your car came backfrom the panel beaters and the door didn't close



 



You've owned a landrover then?  :lol_hitting:
Title: Re: Header clearance issues
Post by: big g on July 15, 2011, 11:43:40 PM
 :iagree: :hysterical:

Good one.