New Combo

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Speedster
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Location: Aloha, Oregon

New Combo

#1 Post by Speedster » Tue Dec 27, 2011 9:49 pm

I'm building a new engine and would like to hear thoughts on this combo.
Dart SHP block 4.125 bore Scat 4340 Crank 3.750 stroke Scat 4340 H beam 6" rod Mahle pistons with the metric rings approx 12.6to1 final compression. Lunati Cam @50 274/282 656/621 lift 106 Lsa AFR 210cc heads Victor intake single plane hp750 MSD billet Dist and 6AL box. the car with me weights 3115# powerglide 4500 stall 4.56 rear gear with 31.0 tire i run 110 octane fuel. Any thing stand out?
Thanks in Advance. oh yeah 1/4 mile car.

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supernova
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Re: New Combo

#2 Post by supernova » Wed Dec 28, 2011 1:13 am

Any head work?
IMO the cam is a little big.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

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wikd69
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Re: New Combo

#3 Post by wikd69 » Wed Dec 28, 2011 3:34 am

Cam size would depend on where you're wanting to spend the power, right ? What RPM range are you looking at ? What stall and what top RPM ?
1969 ProStreet Camaro RS Best 9.75@139 1.46 60'
Blown 427 BBC, TH400 w/Brake, Back-Half Ladderbar
Narrowed 12-Bolt, 4.10 Gears, Spool, Moser 33 Spline

http://www.marsh-racing.com/harrys_camaro-1.htm

want-a-be
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Re: New Combo

#4 Post by want-a-be » Wed Dec 28, 2011 5:53 am

Choice of cam and stall stuck out to me also.

Don

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Speedster
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Re: New Combo

#5 Post by Speedster » Wed Dec 28, 2011 9:15 am

stall is 4500 in a PG trans. i leave on a trans brake. the car with a differant motor was trappin at 6700rpm. i shift at 6100 rpm on old motor. will this cam work? and thanks.

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supernova
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Re: New Combo

#6 Post by supernova » Wed Dec 28, 2011 11:31 am

Is it a solid cam?
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

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spib
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Re: New Combo

#7 Post by spib » Wed Dec 28, 2011 1:29 pm

the stall might be small or I think so and maybee the gear wont be enough, I have a 4:86 gear on a 32 slick and wish I had 5:13 gears my vert is 5400 im 3105
http://www.youtube.com/user/spib43
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want-a-be
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Re: New Combo

#8 Post by want-a-be » Wed Dec 28, 2011 1:30 pm

imo,... this cam is going to want to see the 7k-7.5krpm. More then likely would appreciate a stall of around 5500-6krpm.

just an opinion though.

Don

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wikd69
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Re: New Combo

#9 Post by wikd69 » Wed Dec 28, 2011 2:10 pm

Here's my 2c, for what it's worth...

That sort of cam lift and duration will like it better in the higher RPM. It's about air velocity and flow across the RPM range - high air flow helps transition during RPM changes (gear changes, etc.) and overcomes the tendency to bog at high lift. I'm running a 264 @ .050 duration / .714 lift cam on the street, but it's with a blower - that makes up for the lack of air flow at lower RPM.

Big cam lift and low air flow velocity is why you see those really lumpy NA motors that wont idle below 1600 RPM, etc. So like the last poster said, I'm thinking you'll prolly want to spin your motor up into the mid to high 7K range with that cam.
1969 ProStreet Camaro RS Best 9.75@139 1.46 60'
Blown 427 BBC, TH400 w/Brake, Back-Half Ladderbar
Narrowed 12-Bolt, 4.10 Gears, Spool, Moser 33 Spline

http://www.marsh-racing.com/harrys_camaro-1.htm

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Speedster
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Re: New Combo

#10 Post by Speedster » Wed Dec 28, 2011 7:03 pm

So that cam will want my 4:88's or 5:14's if it's going to work right. I have a smaller crower cam @50 262/272 639/629 lift 105 lsa. it's not much differant. Yes these cams are solid rollers.

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supernova
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Re: New Combo

#11 Post by supernova » Wed Dec 28, 2011 7:54 pm

I agree with "want-a-be", more converter or less cam. If your trying to run max N/A I would go with the bigger converter.......
Last edited by supernova on Wed Dec 28, 2011 9:25 pm, edited 1 time in total.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

User avatar
Speedster
Posts: 183
Joined: Mon Feb 08, 2010 2:35 pm
Location: Aloha, Oregon

Re: New Combo

#12 Post by Speedster » Wed Dec 28, 2011 8:50 pm

Thanks.

mytmouz
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Re: New Combo

#13 Post by mytmouz » Wed Dec 28, 2011 11:34 pm

I like the crower the better of the two with the rest of the combo...
Trucks are for haulin...

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