The Dodge Challenger Message Board

Does someone know about that?
I've collected many opinion from "a must" to "pure crap"....
Thanks for any clarification...

X is better than H. Both give more torque at lower rpms. Peak power is unaffected. Exhaust note will be higher in tone and quieter in volume. Torque converter stall speed may be higher as a result.

On Challengers only the Hemi had a crossover (H-pipe). All other V8s had separate exhaust tubes.

I prefere not to use one because I like the sound of individual pipes much better.

'You sure about that Dave?

I reckon the 440 R/T had an H pipe too. 440 B bodies definitely did.

Pretty sure Jim.

i asume the h pipe your talking about is the ballance tube between the the pipes some people say you get more power. I have a 318 with extractors and twin two and a half inch pipes and the only difrants was it sounded better with the tube.about the cross over x pipes i don't no to much about only that its a performane sistem that is supose to flow better and add hp.

Jim.
You are right about the 440 b-bodies but I am 99% sure that on Challengers only the Hemi had a cross-over/h-pipe/ballance tube (whatever you want to call it). Don't know about Barracudas of course but I would asume the same.

Luke.
When you say more power you are right. BUT NOT PEAK power. I am yet to see any independant scientific tests that show more power at higher rpm and the PEAK power seems about the same. The extra torque at lower rpm does equate to more power at those rpms of course. When you say sounds better that is a matter of taste. I like to hear individual pipes and you get a low pitch blap, blap, blap sound. With the ballance tube the note goes up (because the frequency is higher) and the pressure pulses come out the exhaust both sides together for a smoother sound.

I prefere rough!

The X-pipe is just a better designed ballance tube that works better.

You are dead right Dave!

For some reason Mopar put H pipes on all 440 B bodies from 1967-72, but not 440 E bodies! As you say; only Hemi E body’s got an H pipe. That’s weird.

A famous astronomer once said ‘The more I see, the more I see there is to see.’ That’s true for Mopars too. We learn every day.

Will you and your Challenger be at Avon Park this weekend Dave?

Althought my original 1970 Chrysler Corporation Dodge Service Manual for Dart and Challenger models states at page 11-2:
"The dual exhaust system used on models equipped with the 426 Hemin engine, uses an "H"type exhaust pipe arrangement" (...)
Then there are pictures of single exhaust systems, and dual exhaust systems. The Dart 340 had a dual system, no H-pipe. The 225, 318 and 383-2V challenger had a single system. And under the picture of the dual system including an H-pipe it says:
"Challenger 340, 383-4V, 440-4V and 426 Hemi engines".
Not realy unambiguous, but I tend to judge the "Hemi comment" in the text on page 11-2 to be less excluding other posibilities than the "picture comment" is including them. I hope you all understand what I mean. That is as far as I judge this only source. Any other conclusions from printed sources around, other comments?


Off course I am curious what leaving the H-pipe out would make a difference. But as far as sound is concerned: I like very much the sound of my own car. My 383 Hipo dual blows a dual exhaust with H-pipe with Flowmaster Performance Street strip "40 series" and it sounds low. Lots of low frequencies, very little high frequencies. And medium to fairly loud. Of course a 440 with its longer stroke would sound lower with the same exhaust. But my car sounds lower than most 440's with other systems I came across. Myself I would not go without the H pipe. As far as the stereo effects are concerned, thery are less pronounced but they are still there. And hey, who needs them. And then I myself like any bit of (allmost) free torque. I wish I had chosen an X pipe.

Ciampone, I know you don't have many V8's around, but go check and listen different setups on a meeting.

This just goes to show you shouldn't believe all you see in the manuals.

But the diagram does show a Hemi engine. I am quite sure that no 340 or 383 cars ever had H pipes from the factory. I am also now quite certain that only Hemi E bodies had an H pipe. Why 440 E bodies didn't have H pipes when 440 B bodies did, is anyones guess. I can't think of a good reason why not.

We can only guess. Something to do with production line assembly? Or maybe the heavier(?) b-body needs more bottom end torque? Did they do it so the stall speed was the same using the same converters in the two models?

Because of the valve timing and huge head ports on the Hemi engine it needed all the bottom end help it could get. It made it's power a lot higher up the rpm scale. Less than a 440 at lower rpms. Maybe that's why it had to have one.

Jim.
I should be at Avon park this weekend but I am still not sure if the Challenger will be. The dreaded overheating problem is still there although not half as bad as it was. But it is getting up to 210 degrees already and the ambiant temp is not that high yet. Although by Friday it will be. Looks like I am going to have to do something radical (and expensive) to get on top of this once and for all. I will check the timing curve and give it a try again friday pm with no thermostat but I tried it last night without the thermostat and although the air temp was not that high the water temp still reached 180 degrees. So not looking too good at the moment.

Thanks to everybody for the explanation...
More torque then power at low and mid range, ok.
Wedge b-bodies yes, e-bodies no... very strange, maybe cost reduction?
Just looking at it, X pipe seems better but I think an H pipe is cheaper, I think it's easy to do "homemade".
To Robert : Yes, there aren't many V8s here in Italy, for that reason I'm going to attend in June some meetings in Swiss and to the only one (..!!..) in Italy. Note : not the only one for Mopars, the only one for all usa cars.. I'm sure I'll found there some examples of H and X pipes but Mopars are so rare in Italy, I don't want to look under a C***y to learn!!
Dave, You have been perfect as always
Sound... a matter of taste, ok, but Dave, I'm sure if You'll live in Italy You'll love even the sound of a small block F**d with a single exhaust!
Thanks to all!

Can't understand your overheating problems Dave. Do you mind if i ask a basic question?

I know you've just had a new radiator built. Are you running a Mopar fan with shroud? If not, I reckon that'll solve your problem.

I have wasted enough time on this problem already Jim. I am going for MAX cooling now and sod 'original looking'. I am going to sort this once and for all so I can relax and have FUN this summer!

I understand your frustration with this. There's not much pisses people off more than a motor that keeps overheating!

I was concerned that my engine may overheat with the extra cubic inches and siamese block, which must carry less water and have less efficient cooling around the cylinders.

I asked Ray Barton about this before asking him to build my motor. He assured me the stock cooling system would be adequate, even when driven hard on a hot day or in traffic. He's right too. The needle stays right in the middle of the stock temp guage, never deviating much no matter how I drive it.

So God knows what's wrong with yours Dave, but I sympathise with the misery it causes.

I wonder if someone has fitted a small block radiator to my car at some point Jim. I know the norm is for the top hose to be on the passenger side. I am sure I have seen at least one other 440 with air con and the same top hose location as mine on the drivers side. The top hose that came with the car looks factory made for this application.

To keep in with the theme of my car I would prefer to fit a correct factory unit. But I am not taking any more chances. A Be-Cool custom fit ally radiator has been ordered along with one of Summit's chrome premium electric fans with built-in shroud. If it's not going to look standard it may as well look good eh? I have also ordered a high flow thermostat from Stewart Components.

That should be the end of that problem.

Without consulting my Mopar mags I can't confirm that air con cars had the top hose on the opposite side. I've had several cars with air con, but I can't remember if the hose outlets were any different.

I am quite certain that fitting the correct factory items will look right and work right. Your Be-Cool solution will work OK too. So either way should solve your problem once and for all. Let's hope so.

See you at the Nat's.

Canadian cars has been built with a radiator with in/outlet at the same side. This due the cold weather so they run a bit warmer. Off course these weren't built into a hemi challenger for example.

Mine was not Canadian built but may have started it's life in the Northern states.

That may be it Dave, but finally you will solve the problem for once and for all. (hopefully) See you all at the Nats. (Well, at least we're already planning the trip)

Guess where this is going?

I have no idea! Please, give me a clue! In your daily driver???

Coool stuff Dave!

It'll take me ten years to pay for it though!

Do all those water bottles in the background mean you're only going to put in pure water?

Filtered Newcastle Brown Ale. I have been collecting it for months.

Is that the polished or satin finish on the aluminum raiator?

Satin.

OK, i know i'm only 5 and a half years too late on this, but i am going through the same headbanging. I'm getting a twin 3" system fitted soon (318 for the pits inspection, but big valve 440 intended) and have read a bit of good stuff about the X pipes. However i have been told they really quieten the exhaust- almost to the sound of a single system. Dave, or amyone, in these years have you heard a warm 440 with a twin 3" and X pipe? You said the frequency of the sound goes up, but surely it doesn't sound as bad as a single? I suppose if i want the meaty grumble, i should run separate pipes.