Your donations help keep this valuable resource free and growing. Thank you.
|
headers for 195.6 OHV |
Post Reply | Page 12> |
Author | ||
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7553 |
Post Options
Thanks(0)
Posted: Jan/03/2019 at 12:56am |
|
OK, my big carb seems to be working out (still tuning but so far so good) and thinking the next (and probably final) limitation to flow I have is the single simple exhaust. obviously header systems are not available at Summit.
but I think I figured out how to mock up the shapes necessary to make one from a kit, and maybe even play with lengths before I commit to all the expensive bends -- flexible exhaust. the stuff wouldn't hold up for long but it would sure make it easy to fit to the chassis! and it's super cheap to buy, Walker Flex Exhaust comes in 1.0, 1.25, 1.5, ... 25 ft coils for 40 bucks. I figure I could buy or make a collector, and make the bolt-on port flanges. iv'e got that funny de-siamesed center pair thing going already. assembled in place wouldn't be hard, but they might be too floppy/flexy to retain their shape, to remove from the car and use as models for rigid tubing. but I bet I could make them rigid for modeling by crudely fiberglassing them in-place, on-car, then extract as models. (obviously ones that will never get hot again.) but it seems that modeling headers with flex pipe has gotta be done before. anyone heard of it? this is a 2020 project. got my hands full for this coming year. some things are better cogitated for a while anyway. |
||
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
||
Trader
AMC Addicted Joined: May/15/2018 Location: Ontario Status: Offline Points: 6909 |
Post Options
Thanks(0)
|
|
Do you have a spare engine about?
The reason being, make a mock up and use pre-mandrel bent tubing and weld it. If you set up an engine and fabricate the fender wells out of cheap plywood, you can see and weld as you go, taking the plywood frame away each time. You have the welding skills. You get a perfect fit and design to your standards. You could buy a Jeep header and modify it as well using the same setup. A 1-1/2" to 1-3/4" drivers side 390 header would be a good candidate also.
Edited by Trader - Jan/03/2019 at 7:49am |
||
maynardk
Supporter of TheAMCForum Joined: Aug/16/2012 Location: Roanoke, VA Status: Offline Points: 159 |
Post Options
Thanks(0)
|
|
You may get some ideas from the Clifford Performance headers:
|
||
Ken_Parkman
AMC Addicted Joined: Jun/04/2009 Location: Ontario Status: Offline Points: 1814 |
Post Options
Thanks(0)
|
|
coneeng.com
is a good supplier of components I believe, never used them myself. When I fabricated a set of headers I had a fixture to locate the collector where I wanted - just a simple piece of channel I could clamp the collector to and is repeatable. Then have a box of J bends and cut the bends where you need. The cuts need to be perfect so that you are not filling gaps with weld. I used a tube holder mounted in the mill, and actually milled all the cuts perfectly flat and at the angle I wanted. Tack it in place, then remove the assembly and finish weld. At least that's what I did, no doubt another million ways to skin a cat.
Edited by Ken_Parkman - Jan/03/2019 at 1:46pm |
||
Ken_Parkman
AMC Addicted Joined: Jun/04/2009 Location: Ontario Status: Offline Points: 1814 |
Post Options
Thanks(0)
|
|
OK - I don't know why the link does not work. coneeng.com works here.
|
||
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7553 |
Post Options
Thanks(0)
|
|
trader: yup, I have a spare engine on a stand, head, manifolds etc. dirty cores but good for this.
> you have the welding skills. you're being generous :-) lol, not very good but improving. and maynardk: the catch with this engine (this engine seems to generate every exception possible) is that all of the exhausts are siamesed in a way that would be essentially impossible to split. and the center one has a different shaped port. so part of the research I need to do is to work out the ramifications of that. I know it means the pulse train in each tube isn't symmetrical. ken: thanks for the link. looks like good stuff. (there's an extra space at the end of the URL, shows up as "%20".) I'm OK mocking it up, but worried about the junk down on the drivers side there; starter, steering shaft, throttle cable, clutch linkage, etc. but you're all probably right, external mockup and test is probably the way to go. everything on this car is absurdly small or weird. the exhaust pipe was 1.25" (not a typo), nice blue porcelain. my current 2" pipe runs under the crossmember now. it's why this is a 2020 project. anyone know about the effects of the unsplittable pairs? of course they/re not an even pattern or anything. |
||
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
||
Trader
AMC Addicted Joined: May/15/2018 Location: Ontario Status: Offline Points: 6909 |
Post Options
Thanks(0)
|
|
My cousin used to do open water snowmobile racing, no typo's.
He had to get up to 90 MPH, hit the open water and circle until the thing sank. Most laps won. Anyhow, some snowmobile engines are unsplittable pairs and he made his own headers by doing temperature equalization. Ended up doing the same for his race cars also. Modify the lengths of the exhaust tubes to the collector so the temperatures at 3" from the head were all very close. The engine would be balanced and producing the most HP was his theory. He won enough races, so likely was on to something.
|
||
nickleone
AMC Addicted Joined: Oct/04/2008 Location: westminster co Status: Offline Points: 1446 |
Post Options
Thanks(0)
|
|
nick
401 71 Gremlin pro rally car sold 390 V8 SX/4 pro rally car sold 1962 Classic SW T5 4 wheel disc brakes |
||
g-man
AMC Addicted Joined: Jul/05/2007 Location: Cal Coast Status: Offline Points: 703 |
Post Options
Thanks(0)
|
|
Tom, Let me help you right there...DON'T DO IT! I'm sorry I can't remember when and where, but I read an article in one of the magazines some time ago, that was comparing different types of exhaust systems on a dyno...and I'll never forget this...for some reason they also ran an exhaust made of flexible tubing. To say that it severely affected the output of the motor would be an understatement. Their theory was that the walls of the flex tubing were creating counter pulses that caused restriction in the flow of the exhaust gases. No matter what the reason, it was quite restrictive, and the dyno numbers went WAY down with the flex tube. I wouldn't touch the stuff. g-man
|
||
AMC only daily driver
|
||
tomj
AMC Addicted Joined: Jan/27/2010 Location: earth Status: Offline Points: 7553 |
Post Options
Thanks(0)
|
|
you do realize that is completely insane, right? lol. wow!
ok that sounds very smart (for a crazy person :-). it's hard to find a metric you can actually go by without a building full of test gear. that's a good one! thanks for the idea. I've been curious for a while about exhaust temperature, wanting to measure it and check against tune. it seems like the goal would be (aside from this equalization issue) *lowest* temperature -- energy is produced from the expansion of hot gases, which lowers the temperature. certainly equal in all primaries is a good thing. |
||
1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5 http://www.ramblerLore.com |
||
Post Reply | Page 12> |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |