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OMARS67 12-04-2012 09:58 PM

too much or enough motor
 
a 454 BBC .60 over
21cc dome piston
112cc oval iron head
solid roller 249/255 @ .50 .663/.680 lift
edlebrock victor w/750 dominator

is this ok for daily street use in a 73 corvette w/a muncie??? ok for 91 octane.if i am generous with timing and keep my motor cool say under 200??

vinniekq2 12-04-2012 10:05 PM

750 is too small.I use a 950 on a small block.
the 73 corvette surprisingly hooks fairly well. The muncie wont like all that torque.
you should work out your CR? The oval iron heads need porting,the 265 aluminum AFRs would be nice, or if you step up the cam then 335 dart square ports are nice. The biggest exhaust that fits under that car is only 3 inch,side pipes will kill your ear(s)

spinn 12-04-2012 10:37 PM

If those are your choices, you should know what you will end up with.

That is gonna drive like crap, and be weak on driveability.

Wide open at the track , slipping the clutch with a big gear , will be fun fun fun.

OMARS67 12-04-2012 10:57 PM

Quote:

Originally Posted by vinniekq2 (Post 1619210)
750 is too small.I use a 950 on a small block.
the 73 corvette surprisingly hooks fairly well. The muncie wont like all that torque.
you should work out your CR? The oval iron heads need porting,the 265 aluminum AFRs would be nice, or if you step up the cam then 335 dart square ports are nice. The biggest exhaust that fits under that car is only 3 inch,side pipes will kill your ear(s)

cr is about 10.25 according to my specs given to wiseco. dnt have more cash for aluminum. my iron have 2.19 valves and are ported. i currently run side pipes with my 383. love the sound wont give it up. you think it will ok on the street with 91 octane??

OMARS67 12-04-2012 10:58 PM

Quote:

Originally Posted by spinn (Post 1619221)
If those are your choices, you should know what you will end up with.

That is gonna drive like crap, and be weak on driveability.

Wide open at the track , slipping the clutch with a big gear , will be fun fun fun.

why do you say it wont drive good on the street??

vinniekq2 12-04-2012 11:25 PM

That cam and CR are getting close to max for pump fuel with iron heads.We can ask tech to check the cr for you. We need exact cam specs,intake center line and lobe separation.You might need a bigger cam? I use a bigger cam in a small block with 3.50 gears.I wouldnt want to spend a lot of time in stop and go traffic,unless of course I was at the front at every red light.

My CR is 10.75:1 with aluminum heads

cdminter59 12-05-2012 12:16 AM

too much or enough motor
 
What is your rear gear ratio? You will want a big enough gear to keep you in a 2800-7000 basic operating range. When out cruising you want your rpms around 3000-3500 rpms with that cam.

hcompton 12-05-2012 06:08 AM

Quote:

Originally Posted by spinn (Post 1619221)
If those are your choices, you should know what you will end up with.

That is gonna drive like crap, and be weak on driveability.

Wide open at the track , slipping the clutch with a big gear , will be fun fun fun.

Its a big block that cam is not that big. For a small block maybe but for big block its just normal big not high rpm.

@cdminter59 2800 - 7000 rpm range with a 454. What?? no not that high rpm and the big block will make some good power down low. Did you miss where he said its a 454 bored 60 over. that is a large piston it will take a pretty big cam.

It will be pretty tame since the car is very light and the motor will make alot of tq down low it will pull away from lights gently enough. Engine probably wont even notice the car is connected. But have you thought about an auto. th700r4 would be a much better choice than the muncie. If its numbers matching then pull it and set it aside. The big block will break it for sure at some point if you drive it long enough. Also the auto will be a half second faster in the quarter. Maybe more since you will loose tracktion alot with the big block and heavy clutch.

OMARS67 12-05-2012 07:55 AM

Quote:

Originally Posted by vinniekq2 (Post 1619227)
That cam and CR are getting close to max for pump fuel with iron heads.We can ask tech to check the cr for you. We need exact cam specs,intake center line and lobe separation.You might need a bigger cam? I use a bigger cam in a small block with 3.50 gears.I wouldnt want to spend a lot of time in stop and go traffic,unless of course I was at the front at every red light.

My CR is 10.75:1 with aluminum heads

LSA is 110 and intake center line is 106 making the cam 4 advance. you can get away with more compression because of aluminum. i figure my cam will bleed of some compression so theres not so much cylinder pressure to make 91 octane ok. intake valve closes at 50

spinn 12-05-2012 07:57 AM

Who cares if it is .060" over. Adjust for the compression ratio. Yeah , it is not going to accept that cam any easier because the 454 is .060" over. A big block does have a size and stroke advantage to help with the low end dynamic. Not going to help much for a racing cam. If you have used a cam with lift over .600" , you know how they behave.

You are going to eat up clutch discs.

Sometimes you have to be a little realistic when you build cars that drive on the street with others.

OMARS67 12-05-2012 07:59 AM

Quote:

Originally Posted by cdminter59 (Post 1619242)
What is your rear gear ratio? You will want a big enough gear to keep you in a 2800-7000 basic operating range. When out cruising you want your rpms around 3000-3500 rpms with that cam.

i have stoke gear. not sure what they are maybe 3.60??? im planning on 4.11 the operating range according to lunati is 2500-6800

OMARS67 12-05-2012 08:02 AM

Quote:

Originally Posted by hcompton (Post 1619300)
Its a big block that cam is not that big. For a small block maybe but for big block its just normal big not high rpm.

@cdminter59 2800 - 7000 rpm range with a 454. What?? no not that high rpm and the big block will make some good power down low. Did you miss where he said its a 454 bored 60 over. that is a large piston it will take a pretty big cam.

It will be pretty tame since the car is very light and the motor will make alot of tq down low it will pull away from lights gently enough. Engine probably wont even notice the car is connected. But have you thought about an auto. th700r4 would be a much better choice than the muncie. If its numbers matching then pull it and set it aside. The big block will break it for sure at some point if you drive it long enough. Also the auto will be a half second faster in the quarter. Maybe more since you will loose tracktion alot with the big block and heavy clutch.


yeah im working on the tranny situation. i would like to keep a manual. its currently a m20 im thinking a m22 would be enough??

OMARS67 12-05-2012 08:06 AM

Quote:

Originally Posted by spinn (Post 1619328)
Who cares if it is .060" over. Adjust for the compression ratio. Yeah , it is not going to accept that cam any easier because the 454 is .060" over. A big block does have a size and stroke advantage to help with the low end dynamic. Not going to help much for a racing cam. If you have used a cam with lift over .600" , you know how they behave.

You are going to eat up clutch discs.

Sometimes you have to be a little realistic when you build cars that drive on the street with others.

the words according to lunati:
Product Description

Solid roller, rough idle. Excellent cam for street/strip applications in 427-468 cubic inch engines. Excellent mid and upper RPM torque and horsepower. Needs 3200-3500 RPM stall speed converter, headers, 10.25:1 compression ratio and 4.11 rear gears.
Advertised Duration (Int/Exh): 279/285
Duration @ .050 (Int/Exh): 249/255
Gross Valve Lift (Int/Exh): .663/.685
LSA/ICL: 110/106
Valve Lash (Int/Exh): .018/.018
RPM Range: 2800-7000
Includes: Cam Only

spinn 12-05-2012 08:08 AM

More like 4800 to 6800. Not to be mean, but you guys that are drag racers who been there, you think it will cruise around at 2500 clutch out? Dont go up hill.

It will, but ....not happily.

OMARS67 12-05-2012 08:08 AM

im deffenitaly working to a new tranny. the motor is available and i only have money for one item. and truley the motor is costing me less than a new muncie. my brother is really helping me out being that he got married and is getting out of the hobby:)


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