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Discussion Starter #1
I did the 392 cam swap a month ago with all the same parts that everyone else has used(Except the valve shims).The swap went great i had a dodge Tech help me and everything seems great.I had Johan do the tune and the car has run great i even put 1000 miles on it since the swap and it got like 27 mpg average!The only thing is the car has lost power from stock and i cant figure it out.I have had Johan try different tunes and he says that everything looks good?Something seems to be holding it back its hard to describe but it feels like the engine wants to go but cant?It revs fine all the way to 5600 rpm but just feels flat?The car wont even spin the tires and the exhaust even sounds weird when it goes thru the gears, it seems to flutter more in high rpm.I took it to the track and it only ran 13.8 and 14 sec.Before the swap i ran 13.3s?I have Solo high flow cats on it with cat back exh and cervinis ram air CAI.The only thing i can think thats restricting it is the factory exh manifolds.I didnt think it would actually take hp away using the stock manifolds maybe keep it around the same, it still lets the same amount of air going out the exh from the stock cam?If anyone has anything to add let me know.I dont want this to turn into another 392 cam lost power thread.I can feel there is more there just need to try different things.It almost feels like the timing needs to be advanced so i might ask Johan to try that?
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I had a similar experience in my ram. This cam doesn't make more power than the stock cam until 3600 rpm. Adding longtubes would help but a stall would help even more. That will allow the car to flash higher in the rpm band and get you closer to peak hp.
 

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Discussion Starter #3
I had a similar experience in my ram. This cam doesn't make more power than the stock cam until 3600 rpm. Adding longtubes would help but a stall would help even more. That will allow the car to flash higher in the rpm band and get you closer to peak hp.
Yes i do have a stall converter on my list and you might be right about the power band but i can feel something isn't right its not even making the same power as the stock cam?
 

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I hate to tell you this but the answer to the question is JBA shorty headers. More air and fuel in needs more garbage out, once you look inside the stock manifold you will see what is holding the engine back. The shorty headers are the easiest way to keep it emissions legal in the vampire state of N.Y. The headers on this cars are not as bad as every one seems to think, remember the hardest part of the job is taking the first bolt out. After that your mind set should be on finishing the job.
 

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Without the shims your springs will go into bind, you could have caused issues with your valves. If that is ruled out the headers are a must for more flow.
 
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You mentioned not turning this into a 392 cam lost power thread... well there is a reason you see those pop up quite often... when you put the 392cam in you lose some low end grunt, and that's critical to getting these beautiful heavy cars moving... a higher stall converter is really a must when you put in a cam, so you can get into the power band quicker.
 

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If he used the PSI1511 springs, putting them in without the .010 and.020 shims will put the installed height pressures at 126 #and 122# and this is still more pressure than the stock 392 springs which are 114# + or - 5# both sets of springs are 385# per square inch spring rate with the PSI having more open height before coilbind, which is 1.100 inches or .700 lift the factory spring coilbinds at just over .600 lift should be no problem.
 

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Discussion Starter #8
You mentioned not turning this into a 392 cam lost power thread... well there is a reason you see those pop up quite often... when you put the 392cam in you lose some low end grunt, and that's critical to getting these beautiful heavy cars moving... a higher stall converter is really a must when you put in a cam, so you can get into the power band quicker.
You have a point but im not even getting the higher rpm gains either and there are plenty of guys gaining 50-60 hp from the cam.Something just feels off a bit.

If he used the PSI1511 springs, putting them in without the .010 and.020 shims will put the installed height pressures at 126 #and 122# and this is still more pressure than the stock 392 springs which are 114# + or - 5# both sets of springs are 385# per square inch spring rate with the PSI having more open height before coilbind, which is 1.100 inches or .700 lift the factory spring coilbinds at just over .600 lift should be no problem.
Thats what i thought with the shims too i do have the psi1511s.Do you have headers on yours also?I am just going to order them but i want to make sure its not the timing or something else?
 

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How does the DA compare to each other during your track outings?

Also what was the mph for the before and after the cam swap.Just confirming if you really did lose some power or just different track conditions.
 

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Discussion Starter #10
How does the DA compare to each other during your track outings?

Also what was the mph for the before and after the cam swap.Just confirming if you really did lose some power or just different track conditions.
DA was close to same and lost 2-3 mph in the 1/4.The car can barely spin the tires now.I know that is low end power but the engine really feels like it wants to go but being held back.I know there are a few people that did the swap without headers and didnt seem to loose this much power?
 

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One quick question about your combo, did you use a comp cams phase limiter in your top timing chain gear, which would have limited the amount of cam timing degrees. It seems to me that from what I have read the people that lost power with this cam change used one. the stock cam phaser advances the cam and the engine controller pulls timing out as the RPMs go up(at least this is the way I think it works) so if you put the comp cam limiter in it that would retard the cam timing and that in theory would killing low and mid range and only pick up the very high RPM performance. Which would in theory make the engine feel like it needs more timing. Just my thoughts.
 

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DA was close to same and lost 2-3 mph in the 1/4.The car can barely spin the tires now.I know that is low end power but the engine really feels like it wants to go but being held back.I know there are a few people that did the swap without headers and didnt seem to loose this much power?
Another question what version of the cam did you use? It seems all the big gains were in manuals.
 

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One quick question about your combo, did you use a comp cams phase limiter in your top timing chain gear, which would have limited the amount of cam timing degrees. It seems to me that from what I have read the people that lost power with this cam change used one. the stock cam phaser advances the cam and the engine controller pulls timing out as the RPMs go up(at least this is the way I think it works) so if you put the comp cam limiter in it that would retard the cam timing and that in theory would killing low and mid range and only pick up the very high RPM performance. Which would in theory make the engine feel like it needs more timing. Just my thoughts.
I see your view. I didnt really need to but I used the limiter. Yes correct it will only retard the timing or advance the timing 16deg if I remember correct. That said I lost no power from mine. Reason I stall 4000rpm, with motor stalling like it does the dyno showed my my max RWTQ was at 4200. So im right on the money, per say when the light goes green.
My tuner then works over the tune to bring in my timing fairly aggressive. Even after the shift the timing at wot comes in fast and is aggresive moving up to its max.
Funny the 392 cam shut off like ya killed the motor at 6200. Drops like a rock.

If the tune isnt right there will be a power loss for sure. My tuner had to get the timing tables for the limiter.
Did you tuner get those timing tables ?? There needed.

EDIT: Just noticed Johan did the tuning. He has the tables. lol lol I know that for sure.

FlatTop
 

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Every report that I have read involving this cam and a limiter say power loss. There is your issue.
 

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Discussion Starter #15
One quick question about your combo, did you use a comp cams phase limiter in your top timing chain gear, which would have limited the amount of cam timing degrees. It seems to me that from what I have read the people that lost power with this cam change used one. the stock cam phaser advances the cam and the engine controller pulls timing out as the RPMs go up(at least this is the way I think it works) so if you put the comp cam limiter in it that would retard the cam timing and that in theory would killing low and mid range and only pick up the very high RPM performance. Which would in theory make the engine feel like it needs more timing. Just my thoughts.
Great info but i used the stock limiter but it does feel like timing.

Another question what version of the cam did you use? It seems all the big gains were in manuals.
I used the auto with the mds.

I see your view. I didnt really need to but I used the limiter. Yes correct it will only retard the timing or advance the timing 16deg if I remember correct. That said I lost no power from mine. Reason I stall 4000rpm, with motor stalling like it does the dyno showed my my max RWTQ was at 4200. So im right on the money, per say when the light goes green.
My tuner then works over the tune to bring in my timing fairly aggressive. Even after the shift the timing at wot comes in fast and is aggresive moving up to its max.
Funny the 392 cam shut off like ya killed the motor at 6200. Drops like a rock.

If the tune isnt right there will be a power loss for sure. My tuner had to get the timing tables for the limiter.
Did you tuner get those timing tables ?? There needed.

EDIT: Just noticed Johan did the tuning. He has the tables. lol lol I know that for sure.

FlatTop
I am very surprised the drop off at 6200 i see some people rev it too 6400?Im still working with Johan and im going to ask him to bump up the timing or if i can do it myself with the tuner but i dont know how?

Thanks for all the help guys i will get this figured out.
 

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Discussion Starter #16
Well I had Johan bump the timing up 2* and took it too the track this weekend ran 2 runs and couldn't get any better then 14 sec!Right now im gonna chalk it up to not having headers so im gonna try to get a set.
 

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