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Old 02-28-2007, 05:18 PM   #1
ajroller85

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Default too much cam?

bullet cams recently suggested i use this profile
355 sbo

hydrolic flat tappet
276/286 adv
221/230 @ .050 lift
.485/.485 lift
112 lobe sep
106 lobe center

also happens to be the exact profile of the lunati #318A3LUN
going to a street motor with around 9.5 to 1 compression...maybe lower, pump gas, th350 trans, 3.XX rear gear, 2200-2400stall, i think...not sure how to check it(already in the car)
 
Old 02-28-2007, 05:54 PM   #3
ajroller85

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i dont know the exact rear gear ratio. at 55 mph its at about 2500 - 3000, cant tell what rpm exactly because its got a higher stall than stock...and not sure on stall. runs higher then my 72 with a 273. that runs at about 2100 at 50mph

as to the cr question, im thinking on 9.5, but i dont know all the exact numbers on head cc, deck miling, or head gasket yet...deciding
 
Old 03-01-2007, 02:50 AM   #4
DoubleV
 
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You should call Smitty at M&J performance http://mjproformance.com/ and ask him. He deals with Bullet cams so He should know. You DO need to find out all your other information ( CR and gears for example ) if you want to get the best cam for your motor.
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85 442

Botched Olds 350 build by the crooks at Rocket Racing. Lunati 207/213 Voodoo cam, 8.1:1 CR ( was supposed to be 8.8:1 ), Stock #7 heads ( was charged for work that was never done and what was done was done wrong ), American Racing headers, Performer RPM intake, Qjet with 1/2" 4 hole spacer, 2.5" Pypes X-pipe system, cowl induction scoop.

Engine never ran the way it was supposed to from day one due to Rocket Racing's negligence. John Stolpa refuses to contact me about it.
 
Old 03-01-2007, 12:10 PM   #5
71CutlassConvertible

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Quote:
Originally Posted by ajroller85 View Post
at 55 mph its at about 2500 - 3000, cant tell what rpm exactly because its got a higher stall than stock...
Huh? Why can yo not determine what RPM your engine is turning at 55 mph? Is your tach broken or what? The stall converter should not make the RPM change during steady cruising - I have a 2500 stall and during steady cruising it slips about 200 RPM at any engine speed, either above or below the rated stall RPM.

Anyway, I have the next smaller cam - 217/221 - and it definitely likes the 2500 stall and low gears (I have 3.23 gears and short 25.6" tall rear tires, so it's equivalent to a 3.42 gear with 27" tires). You really need to determine the CR to make certain it is high enough for that cam to perform well.
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Daily Driver - 355 cid, UltraDyne .485/.485, 217/221 cam, Performer RPM intake, 750 cfm QuadraJet, HEI, Heddman Headers, TH350/Hughes 2500 stall, 3.23 limited slip, BFG 245-60-14s on SSII wheels

Last edited by 71CutlassConvertible : 03-01-2007 at 12:18 PM.
 
Old 03-01-2007, 12:55 PM   #7
Smitty275

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FIrst off, just because a cam has same numbers as another does not mean it is same or that it will act same. There are many many variables outside of the numbers.

BUT: if you have the right components to make it work OK then it will be a fine cam for your application. As others have stated you need to find out all the info on your car that you possibly can. If you think it may not have the compression you've listed drop down a notch on cam size. Over camming is worst thing you can do to any motor.
 
Old 03-01-2007, 05:09 PM   #8
ajroller85

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Quote:
Originally Posted by 71CutlassConvertible View Post
Huh? Why can yo not determine what RPM your engine is turning at 55 mph? Is your tach broken or what?
well...the car runs like hammered dogsh@# i wasnt able to keep a steady cruise. it was either all or no go. how would you check the stall speed im my case? rear gear?...with out having to drive the car...stearing column broken
 
Old 03-01-2007, 05:39 PM   #9
oldsdude

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to get a good idea of your rear end gearing. first, jack the rear of the car up and place on good solid jackstands. chock the front tires. now place the car in neutral. make a mark on your tire or axle if the tire is off the car. now make a mark on your driveshaft. now spin the driveshaft and count the number of revolutions it takes to make the tire make one complete revolution. if it takes about three turns you have around a 3.00 gear maybe a 3.08 maybe a 2.93 this technique is not exact but it will get you in the ballpark. Hope this helps.
 
Old 03-01-2007, 05:43 PM   #10
MikeB

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Quote:
Originally Posted by ajroller85 View Post
well...the car runs like hammered dogsh@# i wasnt able to keep a steady cruise. it was either all or no go. how would you check the stall speed im my case? rear gear?...with out having to drive the car...stearing column broken
As for the rear gear here is a good way. Put the rear up on stands put the car in neutral ( Use wheel chocks ! ) mark a line on the driveshaft and on your tires. Spin the driveshaft by hand increments of ten works ok. Count the amount of times you spin the driveshaft and the number of times the tire rotates. There is your ratio. you will get a more accurate result by spinning the driveshaft to a higher number. Yes, it's redneck but it works.
 
Old 03-01-2007, 05:43 PM   #11
71CutlassConvertible

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You can check the rear gear ratio either by:
1) pulling the cover and looking at the stampings on the edge of the ring gear (most accurate)
2) Raise the rear off the ground, turn the wheels one revolution, and count the number of revolutions of the driveshaft (not extermely accurate). If you turn the wheel more than one time then divide the driveshaft revolutions by that number or turns, you can get a better reading.

For the stall converter, you need to be able to punch it from a dead stop without spinning the tires and see what the tach immediately jumps to.
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Daily Driver - 355 cid, UltraDyne .485/.485, 217/221 cam, Performer RPM intake, 750 cfm QuadraJet, HEI, Heddman Headers, TH350/Hughes 2500 stall, 3.23 limited slip, BFG 245-60-14s on SSII wheels
 
Old 03-01-2007, 05:44 PM   #13
MikeB

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Well I'll be damned if I don't feel like an echo.
 
Old 03-01-2007, 05:45 PM   #14
oldsdude

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I think we all had the same thought at the same time. thats weird.
 
Old 03-02-2007, 12:18 PM   #15
Smitty275

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Quote:
Originally Posted by ajroller85 View Post
well...the car runs like hammered dogsh@# i wasnt able to keep a steady cruise. it was either all or no go. how would you check the stall speed im my case? rear gear?...with out having to drive the car...stearing column broken
Are you doing a complete motor build? IF your just swapping in a new cam you should get the car running right and safe to drive first. You don't want to start throwing new speed parts at something that is not functioning properly. The only place that will get you is the poor house.
 
Old 03-02-2007, 01:26 PM   #16
425hpOlds

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Quote:
Originally Posted by Smitty275 View Post
The only place that will get you is the poor house.
In a room right beside mine...

I wouldn't have started my engine build when I did, had the old one not died so soon after I bought the car
 
Old 03-02-2007, 03:42 PM   #17
ajroller85

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no...its a complete motor build up. aimed at my brother, hopefully keep up with his blown pontiac, runs a 13.2 in the 1/4, if not, oh well
 
 


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