Ad Radar
Facebook Click here to find out more!

Exhaust Heat Riser Position

  
Mopar Muscle
Item Posts    Sort Order

Exhaust Heat Riser Position

 
64Valiant200convV8 64Valiant200convV8
New User | Posts: 46 | Joined: 10/08
Posted: 01/03/13
06:14 PM

I have a '72 Scamp 225 slant 6 4 bbl that starts pretty rough when cold.  I have researched this and besides having other issues with my crab and choke, I need to reinstall the heat riser counter balance, stop and spring that was missing from my car when I bought it. The damper seems to have more travel than the stop spring will allow. The question is when installing the counter balance, what position should the damper be in. Should I close the damper and install the counter balance in the fully closed position or should I open the damper and install the counter balance in the fully open position? Or something in between? I would think the damper should be full open when hot and if it doesn't close all the way when cold - that's OK. The other way it wouldn't open all the way when hot and that will restrict flow. Thoughts? No I don't want to just leave it off.  Thanks.  

waynep71222 waynep71222
User | Posts: 246 | Joined: 04/12
Posted: 01/03/13
08:57 PM

i think that the blade hits the stainless gasket and thats what limits the opening...  




but which intake do you have??? with a 4 bbl that would warm the incoming air charge..

45 4500WH%20300

or the hyperpack

1962 Plymouth Valiant Slant Six Motor Clifford Block  

64Valiant200convV8 64Valiant200convV8
New User | Posts: 46 | Joined: 10/08
Posted: 01/04/13
04:00 PM

I have the Offenhauser 4bbl intake with the stock mating surface to the stock exhaust manifiold.  When the damper is rotated w/o the stop spring it turns about 160 degrees or from 12 o'clock to 5 o'clock.  With the stop spring on, it only turns 90 degrees or from 12 to 3 o'clock.  Not sure how to attach images but try this.  
135
http://www.offyparts.com/product_info.php/cPath/1_9/products_id/135  

waynep71222 waynep71222
User | Posts: 246 | Joined: 04/12
Posted: 01/04/13
04:58 PM

i have not had one of those in my hand in 2 or 3 years... and i did not measure the angles..

i just made sure that in the closed position.. the exhaust flow was blocked from going straight down the exhaust pipe and directed up against the bottom of the intake plenum.. then over and down to get out.. this warms the plenum..  

64Valiant200convV8 64Valiant200convV8
New User | Posts: 46 | Joined: 10/08
Posted: 01/06/13
10:39 AM

Thanks for the response.  I set it up with the damper in what I think is the full open position when the spring is hot.  This gives me full power.  I think it may not close all the way but I am still getting some flow up and over warming the plenum.  The way it is set up I think the exhaust pushes open the damper on acceleration if it is partially closed anyway.  So it only really heats the plenum at idle.  I have a scope electricians use to look in walls and next week I will look up through the cut out and see whats really happening.  Not while its running of course.  The test run yesterday ran pretty well.  Sure wish I lknew how to post pictures on this site.  Mine are jpegs not https???