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Porting CJ/SCJ DOOE-R heads
October 27 2000 at 1:19 PM
No score for this post Mike R. (no login)
from IP address 32.97.239.19
--------------------------------------------------------------------------------
Hi guys, glad to see a new forum on these 385 series engines.
I noticed there was some interest on this forum about porting CJ/SCJ heads. I have a couple of sets of the DOOE-R heads that I've done alot of work on. I also have a cross sectioned chunk of a CJ head. I have tried alot of different things with these heads from racing my 70 Torino Cobra. This winter I'm going to pull the set that's on my Cobra and get them flow tested and try some different things to see if I can further improve them.
It seems like it's hard to come by flowbench data on the iron CJ/SCJ heads. After I get the flow data and try the new tricks I'd be happy to post the info if anybody's interested.
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Author Reply
Alan Casida
(no login)
12.13.248.3 CJ heads
No score for this post October 27 2000, 1:50 PM
That would be great! I've got a pair I'm planning
on using next year and would appreciate all the info I can get.
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RJP
(no login)
152.163.207.82 Count me in too
No score for this post October 27 2000, 7:45 PM
Have a set sitting around and would like to know if the effort is worth it, if it is I might just throw them on something and run 'em. A few years ago I ran them on a boat and couldn't tell much difference between them and a set of D0VE-C heads.
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Dave C
(no login)
165.247.0.149 CJ/SCJ Porting
No score for this post October 30 2000, 9:30 PM
Mike I am interested in what you have done at this point. How has the work you have done effected ET and MPH. Did you focus on the valve bowels, intake/exhaust, exhaust port hump. Have you tried filling in the dead space on the exhaust port like those port plates do. Any how I am interested in any info you could share.
Thanks
Dave C
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Mike R.
(no login)
4.16.47.21 cj/scj head porting
No score for this post October 30 2000, 11:31 PM
I did alot of work on the exhaust ports to start. I totally removed the thermactor bumps and filled the hole. I ground both of the bumps on the valve guides down and smoothed the guide into a cone shape that smoothly blends into the valve stem. I ground out the tall vertical bumps on each side of the port exit and widened the port greatly deep into the port as much as I could without getting into the head bolt hole. I raised the roof of the port somewhat as well. I smoothed out the bowl area on both intake and exhaust as well as gasket matching. I'm not aware of a port plate being available for the CJ heads so I haven't tried that. I think the bottom side of the port on a CJ head may not be as deep as some other castings though.
I did alot of work in the combustion chambers deepening the pockets around the valves to unshroud the valves and help mid lift flow. I also smoothed all surfaces in the combustion chambers and polished them.
Unfortunately I was not able to do back to back testing to see the horsepower difference. I do know that they must flow pretty decent because my 4000# street torino cobra ran 11s in full street trim last weekend. So I've been really pleased with their performance up to now.
Hopefully the flow testing will give some indication of what kind of improvements I have made to them because I have the stock flow #s for iron CJ heads that I can compare them to.
I would really like to do some more work to the intake ports and maybe a little more to the exhaust ports. I'm probably going to try some before and after flow testing to see if there is much more to gain.
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Fred R
(no login)
142.194.117.151 stock SCJ Flow #
No score for this post October 31 2000, 9:55 AM
Do you think you could post the flow numbers for the stock SCJ heads?
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Mike R.
(no login)
32.97.239.26 stock flow #s
No score for this post October 31 2000, 11:51 AM
I don't have the info in front of me but my best recollection is that it was about 276 max cfm for intake and 148 max cfm for the exhaust. I'll double check it and make sure this is correct. I think the aluminum CJs in stock form were about 296 and 176 respectively.
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James
(no login)
206.173.188.43 Headers
No score for this post November 2 2000, 11:59 PM
Since your heads flow so well, what kind of headers/exaust system do you have?
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Mike R.
(no login)
32.97.239.23 headers
No score for this post November 3 2000, 12:12 PM
I'm currently using the hooker #6115 (1-7/8") headers with 3" exhaust and 3" flowmaster mufflers. I have a set of hooker #6201 (2-1/8") headers ready to install this winter. I've wondered for a long time just how much (if any) difference these bigger tubes will make. I do have a dyno article that shows huge hp and torque gains using these #6201 headers, but the headers they compared them to were shorter than my #6115s. I guess the best way for me to find out is to try them.
October 27 2000 at 1:19 PM
No score for this post Mike R. (no login)
from IP address 32.97.239.19
--------------------------------------------------------------------------------
Hi guys, glad to see a new forum on these 385 series engines.
I noticed there was some interest on this forum about porting CJ/SCJ heads. I have a couple of sets of the DOOE-R heads that I've done alot of work on. I also have a cross sectioned chunk of a CJ head. I have tried alot of different things with these heads from racing my 70 Torino Cobra. This winter I'm going to pull the set that's on my Cobra and get them flow tested and try some different things to see if I can further improve them.
It seems like it's hard to come by flowbench data on the iron CJ/SCJ heads. After I get the flow data and try the new tricks I'd be happy to post the info if anybody's interested.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Author Reply
Alan Casida
(no login)
12.13.248.3 CJ heads
No score for this post October 27 2000, 1:50 PM
That would be great! I've got a pair I'm planning
on using next year and would appreciate all the info I can get.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
RJP
(no login)
152.163.207.82 Count me in too
No score for this post October 27 2000, 7:45 PM
Have a set sitting around and would like to know if the effort is worth it, if it is I might just throw them on something and run 'em. A few years ago I ran them on a boat and couldn't tell much difference between them and a set of D0VE-C heads.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Dave C
(no login)
165.247.0.149 CJ/SCJ Porting
No score for this post October 30 2000, 9:30 PM
Mike I am interested in what you have done at this point. How has the work you have done effected ET and MPH. Did you focus on the valve bowels, intake/exhaust, exhaust port hump. Have you tried filling in the dead space on the exhaust port like those port plates do. Any how I am interested in any info you could share.
Thanks
Dave C
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Mike R.
(no login)
4.16.47.21 cj/scj head porting
No score for this post October 30 2000, 11:31 PM
I did alot of work on the exhaust ports to start. I totally removed the thermactor bumps and filled the hole. I ground both of the bumps on the valve guides down and smoothed the guide into a cone shape that smoothly blends into the valve stem. I ground out the tall vertical bumps on each side of the port exit and widened the port greatly deep into the port as much as I could without getting into the head bolt hole. I raised the roof of the port somewhat as well. I smoothed out the bowl area on both intake and exhaust as well as gasket matching. I'm not aware of a port plate being available for the CJ heads so I haven't tried that. I think the bottom side of the port on a CJ head may not be as deep as some other castings though.
I did alot of work in the combustion chambers deepening the pockets around the valves to unshroud the valves and help mid lift flow. I also smoothed all surfaces in the combustion chambers and polished them.
Unfortunately I was not able to do back to back testing to see the horsepower difference. I do know that they must flow pretty decent because my 4000# street torino cobra ran 11s in full street trim last weekend. So I've been really pleased with their performance up to now.
Hopefully the flow testing will give some indication of what kind of improvements I have made to them because I have the stock flow #s for iron CJ heads that I can compare them to.
I would really like to do some more work to the intake ports and maybe a little more to the exhaust ports. I'm probably going to try some before and after flow testing to see if there is much more to gain.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Fred R
(no login)
142.194.117.151 stock SCJ Flow #
No score for this post October 31 2000, 9:55 AM
Do you think you could post the flow numbers for the stock SCJ heads?
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Mike R.
(no login)
32.97.239.26 stock flow #s
No score for this post October 31 2000, 11:51 AM
I don't have the info in front of me but my best recollection is that it was about 276 max cfm for intake and 148 max cfm for the exhaust. I'll double check it and make sure this is correct. I think the aluminum CJs in stock form were about 296 and 176 respectively.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
James
(no login)
206.173.188.43 Headers
No score for this post November 2 2000, 11:59 PM
Since your heads flow so well, what kind of headers/exaust system do you have?
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Mike R.
(no login)
32.97.239.23 headers
No score for this post November 3 2000, 12:12 PM
I'm currently using the hooker #6115 (1-7/8") headers with 3" exhaust and 3" flowmaster mufflers. I have a set of hooker #6201 (2-1/8") headers ready to install this winter. I've wondered for a long time just how much (if any) difference these bigger tubes will make. I do have a dyno article that shows huge hp and torque gains using these #6201 headers, but the headers they compared them to were shorter than my #6115s. I guess the best way for me to find out is to try them.
