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Another update on my 408- advance cam next?
#1494884
09/02/13 10:54 AM
09/02/13 10:54 AM
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Joined: Apr 2009
Posts: 3,422
Toronto
mshred
OP
master
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OP
master
Joined: Apr 2009
Posts: 3,422
Toronto
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As some of you have been following my progress this might seem like it was a long time coming lol I am having a hard time getting my car to run where I want it to and have tried a bunch of things. I just got my converter back from getting loosened this past week and took it to the track. Converter is flashing higher (about 53-5400rpms) and seems like the dead spot before the 60 ft is gone or atleast mostly faded away (my 60's on the first pass with way lean jetting were already much better at 1.51 so I know the re-stall was in the right direction). Car is heavy and im thinking I need to advance the cam to get anything better out of it though in terms of e/t and mph (that is if cam advancing even helps those numbers). Cam specs are 251/260 at .050 duration .591 lift int/exh 108LSA installed straight up Solid flat tappet Engine is a 408ci pump gas mopar (10.5:1), 5400 8" converter, 4.10 gear, 28" tire, Victor single plane intake, 850DP carb on top of a 1" tapered spacer, 3500lbs race weight. Can't seem to better an 11.28 at 117.8mph in real bad heat, and thats after getting the hook down, having the converter loosened, and playing with jetting and timing and plug heat ranges to get them optimized (I had to drop from an NGK -6 to a -8 in order to get the plugs to show some color and be able to put some timing to it without getting detonation- not sure if this is normal on an iron head, but it seemed to work for me). Will advancing this cam give me any gains in e/t and mph? Im thinking 60's should improve which should show in e/t given the added torque. Trying to run a 10.90 class with this thing and am having a hard time getting there. Here is a video from my last outing on Saturday. It was unbelievably hot and humid, and a buddy of mine was telling me that I could definitely get more out of it when its cooler, but I want this thing to go 10.90's in the heat, and im thinking advancing the cam is the only thing left to get this pig of an a-body moving. http://www.youtube.com/watch?v=fS5irtqoIJA&feature=youtu.beI think I have already actually made up my mind to advance the cam, but curious to see what others have to say about this. If anyone is running a 408 like myself with an advanced cam, can you please post your cam specs, how much advance and what LSA, and what the car 60's, e/t's and mphs? I guess I just have to keep plugging away at this thing, but im running out of things to try lol Thanks! Matthew
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Re: Another update on my 408- advance cam next?
[Re: mshred]
#1494885
09/02/13 11:24 AM
09/02/13 11:24 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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I normally advance the cam in any of my engines... but it also knocks out some of the top end rpm... do you use the top end rpm(is your set up stringing out the revs or is there wasted rpm available)... I usually advance the cam 4* to 6* depending on the cam and set up... I didnt advance the cam in the Rampage because I didnt want any more torque to stall the conv higher.. its already 5000 and its a street car.. that cam is a 105 LSA installed at 105 
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Re: Another update on my 408- advance cam next?
[Re: mshred]
#1494886
09/02/13 11:48 AM
09/02/13 11:48 AM
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Joined: Jan 2007
Posts: 8,043
Mt Morris Michigan
mopar dave
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master
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Mt Morris Michigan
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my 408 has indy heads that flow 325@.700 and my lastest cam works real nice with this combo. my cam is a 260/269@50 about .700 lift and ground on a 106 LS installed at 100.5*. bullets target install spec was 100-102. my compression is 11.4:1 and my timing is locked out at 34*,but I think it may like 36* better. your 408 still sounds like it struggles a bit before getting up on the power. I don't know if it would make a big difference in your 60 advancing the cam,but it sure wont hurt. I would have your cam in at 104*. my vert stalls at 5500 and is an 8". hope this helps.
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Re: Another update on my 408- advance cam next?
[Re: MR_P_BODY]
#1494887
09/02/13 11:49 AM
09/02/13 11:49 AM
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Joined: Apr 2009
Posts: 3,422
Toronto
mshred
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OP
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Toronto
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Quote:
I normally advance the cam in any of my engines... but
it also knocks out some of the top end rpm... do you
use the top end rpm(is your set up stringing out the
revs or is there wasted rpm available)... I usually
advance the cam 4* to 6* depending on the cam and set
up... I didnt advance the cam in the Rampage because
I didnt want any more torque to stall the conv higher..
its already 5000 and its a street car.. that cam is
a 105 LSA installed at 105
I shift around 6700rpms, but I could shift higher if I wanted to, though I don't see the benefit because the car is making much more power up there. I realize that advancing will bring the peak power down some, but im thinking that it will really help get this moving off the line, which is where it seems to really be dogging it, although my mph is still low as well.
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Re: Another update on my 408- advance cam next?
[Re: sshemi]
#1494890
09/02/13 12:08 PM
09/02/13 12:08 PM
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Joined: Apr 2009
Posts: 3,422
Toronto
mshred
OP
master
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OP
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Toronto
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Quote:
You should try a ported ebrock airgap intake with a one inch open spacer.
I actually still have my airgap (non ported) and 1" open spacer from my last two builds sitting on the shelf in the garage. Brian at IMM says I should try the intake swap as there will be a noticable gain in power below 5500rpms. But I have some time invested into this single plane and im thinking since the car is spending time above 5500rpm on the track that keeping the single plane if it outperforms the airgap at those levels might be a good idea?
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Re: Another update on my 408- advance cam next?
[Re: mopar dave]
#1494891
09/02/13 12:10 PM
09/02/13 12:10 PM
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Joined: Apr 2009
Posts: 3,422
Toronto
mshred
OP
master
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OP
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Posts: 3,422
Toronto
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Quote:
my 408 has indy heads that flow [Email]325@.700[/Email] and my lastest cam works real nice with this combo. my cam is a 260/269@50 about .700 lift and ground on a 106 LS installed at 100.5*. bullets target install spec was 100-102. my compression is 11.4:1 and my timing is locked out at 34*,but I think it may like 36* better. your 408 still sounds like it struggles a bit before getting up on the power. I don't know if it would make a big difference in your 60 advancing the cam,but it sure wont hurt. I would have your cam in at 104*. my vert stalls at 5500 and is an 8". hope this helps.
Yea, from what I have seen alot of the mopar sb's, even strokers, are running advanced camshafts. I agree, it still does sound like it is struggling before getting into the powerband. The looser converter definitely helped, but I still think the bottom end needs to be improved, especially with my car weighing what it does.
I feel like advancing the cam is just another thing to try to see if the car will respond or not. I have a feeling it won't pick up the car to where I am hoping, BUT, its worth a shot I think to see what gains I might make with it.
Thanks for the input Dave!
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Re: Another update on my 408- advance cam next?
[Re: mshred]
#1494892
09/02/13 12:15 PM
09/02/13 12:15 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Quote:
You should try a ported ebrock airgap intake with a one inch open spacer.
I actually still have my airgap (non ported) and 1" open spacer from my last two builds sitting on the shelf in the garage. Brian at IMM says I should try the intake swap as there will be a noticable gain in power below 5500rpms. But I have some time invested into this single plane and im thinking since the car is spending time above 5500rpm on the track that keeping the single plane if it outperforms the airgap at those levels might be a good idea?
Next question... do you leave off a trans brake or
foot... whats the lowest rpm you see on the track
and that means on the launch also
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Re: Another update on my 408- advance cam next?
[Re: mshred]
#1494894
09/02/13 12:26 PM
09/02/13 12:26 PM
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Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Dodgem
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master
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Posts: 5,746
Ontario, Canada
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My opinion is the cam needs to be advanced a little more definetily try it it can be put back one thing at a time.
Higher shifts have too things motor is an air pump the faster it spins the more air it pumps (and power it makes overall)
The other is shift recovery play with that after advancing the cam.
Last edited by Dodgem; 09/02/13 12:27 PM.
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Re: Another update on my 408- advance cam next?
[Re: Crizila]
#1494899
09/02/13 03:33 PM
09/02/13 03:33 PM
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Joined: Jan 2003
Posts: 6,591
Canton, Ohio
Sport440
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master
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Canton, Ohio
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Actually like Crizilla states, with your new 1.51 60 ft, your incrementals are all inline. My Optimum Chassis setup chart shows that for 118 MPH in the 1/4 the incrementals on a Well set up car should be close to these numbers. 1.52 60ft. 7.14 1/8 11.25 1/4 @ 118 MPH your, 1.51 60 ft. ??? 1/8 11.28 1/4 @ 117.8 MPH Your pretty much spot on. But I would still advance the cam though, because like Criz states, We Like it that way around here,. 
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Re: Another update on my 408- advance cam next?
[Re: Sport440]
#1494900
09/02/13 05:22 PM
09/02/13 05:22 PM
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Joined: Apr 2009
Posts: 3,422
Toronto
mshred
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Toronto
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The fact that my incrementals are all inline with eachother is what has me a little upset...I built this thing to run 10.90's and im struggling to even get 11 oh's out of it. I am running IMM prepped and ported RHS X heads that flow 291/212 cfm at .600"...I agree that the converter could have been loosened more, but at this point sending it back out is not feasible (its almost $450 to get it re-stalled which was covered by them this past time, but next time around I would have to pay...plus the 100 bucks in shipping there and back  )...However, its definitely an improvement over how it was stalling before I too am thinking that advancing the cam might not really give me much improvement, if any, at all....but its worth a try right? Maybe the car will pick...atleast I sure as heck hope so...otherwise this winter its back to the drawing board to figure out how to get more power out of this thing.
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Re: Another update on my 408- advance cam next?
[Re: sshemi]
#1494903
09/02/13 05:41 PM
09/02/13 05:41 PM
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Joined: May 2004
Posts: 3,210
robin hood country
deaks
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master
Joined: May 2004
Posts: 3,210
robin hood country
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I know you're against it but i would uncork the exhaust, let them extra horses out. You dont have to take it off just unbolt it from the headers move it across and stick one bolt back on each side.
A car as heavy as yours is going to need at least 121 to hit a high 10.90.
Mick
69 Dart GTS 440 mopar .590 cam, Edelbrock heads, 3200#
best et 6.45, 106.78, 10.14, 132.88 mph, 1.47 60ft
best 60ft 1.36
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Re: Another update on my 408- advance cam next?
[Re: mshred]
#1494904
09/02/13 05:52 PM
09/02/13 05:52 PM
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Joined: Jan 2003
Posts: 32,394
Quicktree
I Win
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I Win
Joined: Jan 2003
Posts: 32,394
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Quote:
The fact that my incrementals are all inline with eachother is what has me a little upset...I built this thing to run 10.90's and im struggling to even get 11 oh's out of it. I am running IMM prepped and ported RHS X heads that flow 291/212 cfm at .600"...I agree that the converter could have been loosened more, but at this point sending it back out is not feasible (its almost $450 to get it re-stalled which was covered by them this past time, but next time around I would have to pay...plus the 100 bucks in shipping there and back )...However, its definitely an improvement over how it was stalling before
I too am thinking that advancing the cam might not really give me much improvement, if any, at all....but its worth a try right? Maybe the car will pick...atleast I sure as heck hope so...otherwise this winter its back to the drawing board to figure out how to get more power out of this thing.
maybe you are asking for to much at 3500lbs. low compression, steel heads, small cam 
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Most SB really like having the cams in at or more than 106 to 100 on the intake lobe centers 
