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Re: 1st time on track little dissapointed
[Re: T-bar]
#1229167
05/09/12 08:56 PM
05/09/12 08:56 PM
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Joined: Feb 2005
Posts: 4,313
Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,313
Prospect, PA
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Quote:
Hay Kevin, yes it's been two years since i got the car and had a ball racing again as it's been about twenty years between runs. The car weighs 3630 with me in, standard springs that have been reset down, with kyb gas adjustable shocks on rear and standard shocks on the front. It launched fairly even and straight.
Hmmm. Twenty years....Maybe go back to the track a couple more times just to get more seat time and your driving skills sorted out....launch, shift points maybe a couple of carb adjustments before you go making engine changes. 
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Re: 1st time on track little dissapointed
[Re: T-bar]
#1229168
05/09/12 09:38 PM
05/09/12 09:38 PM
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Joined: Feb 2004
Posts: 964
Nanaimo, B.C.
GwaiiEagle
Mannix
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Mannix
Joined: Feb 2004
Posts: 964
Nanaimo, B.C.
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Quote:
Now the combo is
496rb
10.5 compression
flat tappet .565" lift on both and .274 deg @ .50
eddy rpm performer heads with light porting (no flow numbers)
440 victor intake
1050 quick fuel carb 4150
converter stalls around 3500 (unsure)
727 full manual
3.91 diff gears
295/65r15 mickey thompson et's
So any thoughts?
Something is Wrong here.
Here's my combination which ran a best of 7.43 at 92 mph with a 1.62 60 ft.
Not really loading up on the car.
'74 Duster
448 0.020 over 3.75 stroked 400 block.
OOTB 84 closed chambered Eddy heads
KB 280 with quench dome milled off. 10.2:1
Magnum series Comp Cams 282S (236 at 50 .528 lift with a 1.6 ratio rocker arm).
Performer RPM 383
Holley 850DP 1 inch 4 hole spacer.
727 w/11 inch converter
1.75 headers to a 3 inch exhaust.
28x9 slick on a 3.91 gear.
Your mill is better all around than mine must be a tuning thing or you`re not launching hard enough.
What altitude is the track, not 4000ft or something...
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Re: 1st time on track little dissapointed
[Re: BSB67]
#1229169
05/09/12 09:49 PM
05/09/12 09:49 PM
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Joined: May 2009
Posts: 62
montreal, quebec,canada
7e5dartsport
member
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member
Joined: May 2009
Posts: 62
montreal, quebec,canada
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tbar,i looked at cam-quest6 for a cam that migth better fit your combo. comp cams xs290s is the best solid i found .they recommend 3500 stall and 10.5 compression, which would work with what you already have. it would even be streetable and you could probably reuse your valve springs. no head machining necessary either( around same lift as the old cam). i know you would prefer a solid roller, but you could just slip this one in and it would improve torque a bunch and probably hp too. both of which should improve your 60 foots.but, if it was me, i would fine-tune the advance curve in the distributor( locked-out?) and tailor the carb`s accelerator pumps before the cam change.
Last edited by 7e5dartsport; 05/09/12 09:52 PM.
fully legal sounds the same as full illegal...
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Re: 1st time on track little dissapointed
[Re: moparmanjames]
#1229172
05/11/12 07:56 AM
05/11/12 07:56 AM
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Joined: Jan 2003
Posts: 9,996
Frostbitefalls MN (Rocky&Bullw...
gregsdart
master
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master
Joined: Jan 2003
Posts: 9,996
Frostbitefalls MN (Rocky&Bullw...
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Quote:
Quote:
Is it worth the time in advancing that cam if the duration is to wide? or should i change it out? I don't have anymore info on it then what i've listed. I thought i had the tune down pretty good from the chassis dyno. I did try different launch rpm's and shift points. I do understand that the 60' is critical and until i sort that it's gonna be slow. With a correct cam for this engine wouldn't it be ideal to have the heads flowed? 
Flowing the heads would cost money that you could be putting into the cam.
I would change the cam out with one that has a 106 to 108 lobe separation angle, and a duration at .050 of around 260 to 270 @ .050" lift, preferrably 260 for great mid range torque.
Advance it 4 degrees if it doesn't already come that way (advance ground in)and hang on.
You're converter will stall higher, you won't have to change gear or tire.
The cam, compression, head work and converter all effect on another, and the dominator is going to like lots of stall. In order of what to do, I would go with a cam first, compression and some port work next, then match the converter with plenty of stall to work well with the dominator. Gears would come last, as they won't be worth near as much in ET gain if the converter is stalling up where it needs to be.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
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Re: 1st time on track little dissapointed
[Re: Dodgem]
#1229175
05/11/12 04:43 PM
05/11/12 04:43 PM
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Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Dodgem
master
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master
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
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where that cam is installed now makes your dynamic compression about 7.5 to 1 and cranking compression is likely about 145
advance it to 106 and your dynamic will go to about 8.3 and cranking to 165 assuming it is 10.5 to 1.
Last edited by Dodgem; 05/11/12 04:46 PM.
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Re: 1st time on track little dissapointed
[Re: T-bar]
#1229176
05/11/12 04:59 PM
05/11/12 04:59 PM
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Joined: Jan 2003
Posts: 16,925
NC
440Jim
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,925
NC
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The 274 duration at 0.050" is a little on the high side for only 10.5 CR, but with 496 CID it might be OK. However, that much duration will really like more stall speed, 4000 minimum and the more the better. That should enable 1.5x sixty foot times (2 tenths right there).
Get the cam position checked. If it is retarded, that is killing it. If it really has a 114 lobe separation angle (lobe centers), then 3 degrees retarded would put the intake lobe installed position at 117 degrees after top center (ATC). Just moving it to 108-110 ATC would help some. Maybe the guy meant 114-3= 111 ATC which is OK. This can be checked with some timing tape on the damper and a dial indicator on the pushrod. Piston to valve clearance will be changed by advancing the cam...
I think the 3.91 gear is fine even if a little more might be optimum. I estimate that tire is close to 30" dia, so a little shorter will act like more gear ratio.
Although the Victor is a great intake, the Edelbrock RPM dual plane will work great up to around 6000 rpm and improve low rpm drivability also.
My suggested order:
1) Check cam, set installed position if off
2) Swap intake, easy and not expensive
3) It really needs more converter stall speed
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