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Old 03-07-2012, 06:51 PM
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camshaft suggestions

he guys i just built a 390 it has stock bore with speed pro pistons iron ford heads ported an it has cobra jet valves with stock non. adjustable rockers and i have a rear end ratio of 3.50 a standard tranny i want it to be a very fast street car that i can take to the strip every once in a while any input woulb be great. thanks!!!!!!

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Old 03-07-2012, 06:55 PM
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Need more info. What intake? What carb? Headers? Exhaust? Compression ratio? What ignition?
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Old 03-07-2012, 07:24 PM
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i think i will get a 750 edelbrock a performer rpm intake and the compr. ratio is like 10.1 or somthin i am not sure i got the speed pro pistons of my machine shop buddy. hope this helps thanks
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Old 03-07-2012, 07:25 PM
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ow ya the ignition is mallory with a msd coil and hedman headers thanks!
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Old 03-08-2012, 12:59 AM
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With what you have this will give you "good bang for the buck" http://www.summitracing.com/parts/HRS-CL250031-12/ I would advise you to get new matching valve springs.The lift is about max before you would require adjustable rockers.Before you plunk down the buck for that Edelbrock RPM you might want to do some research on Jay Brown's dyno test on FE intakes and check ebay for an Edelbrock Streetmaster you can learn a lot here http://www.network54.com/Forum/74182/search

Last edited by JeffB; 03-08-2012 at 01:18 AM.
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Old 03-08-2012, 08:39 AM
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thank you does a bigger cam really gain that much horsepower? i think i will goe with something like that. and how much spring do i need?
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Old 03-08-2012, 09:34 AM
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Comp Cams #33-600-5. look it up.
You will need a suitable hi performance valve spring.
you may have to get a custom length pushrod.
To get proper hyd lifter plunger depression.

you won;t know that until you mock up the valve train assembly.
A clue would be to measure the cam lobe base circle of your stock cam
and compare to the new comp cam.
A change in cam lobe base circle will require a custom length pushrod or conversion to a adjustable rocker system.

I highly recomdn that you accuratly "degree in" this cam to get max performance. Some of the Ford timing gear sets are funky.
Its all about the details.

Verify the real compression ratio. You want as close to 10:1 as possible.
Ya it matters
When at the track un cork the headers and run 12"-18" of collector extensions.
Get some sticky ( M/T ET Street) tires, traction bars and a drive shaft safety lope.
The distributor will need to be recurved for this cam.

it has a modest .500" valve lift which should be fine with the stock FE rockers system. Its up to you to check this and do a proper cam installation.
This cam will give very good power in the rpm you will be using at the track.
especially when uncapped with the collector extensions.

Call Comp Cams for tech advice: Don;t be shy, thats what they are there for.

The performer RPM intake and a 750DP is your best bet.
When you get adventureistic try some 4.11 gears in your Fairlane.

Shift it about 5800rpm.
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Old 03-08-2012, 10:12 AM
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When you want to limit yourself to a stock 390FE motor valve train
you have to limit the valve lift. You must check and verify the valve lift capability (lift travel limit) of your stock rockers.
Comp cams may want to make you a Custom grind cam to get this just right.
Call them. They will help you get this right.
Plan on needing to accuratly determine the Hyd lifter preset plunger depression
and getting custom length pushrods to get this right.
Proper install is critcal when ever using a non adjustable valvetrain
( Ford FE, Olds V8 etc)

Don't be intimidated by a custom grind cam. Or calling for this.
Thats what these cam companies do, every day..
They may want to go with a slightly different cam lobe, for you.

www.compcams.com
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Old 03-08-2012, 03:49 PM
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thanks

thanks i am not sure how to use a cam degree wheel i have one but it kinda confuses me.
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Old 03-08-2012, 09:08 PM
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Quote:
Originally Posted by 64 fairlane 500
thanks i am not sure how to use a cam degree wheel i have one but it kinda confuses me.
64: Listen to fire bird hes telling you exactly what I told you in the P.M. yesterday (hes dead on) Lifter lash is set at full collapse and adjusted with lash caps or different length push rods there are no short cuts!!! Tell these guys your age!!! and experience! it will help them help you! The rpm air gap is not a good choice for F.E.side oilers the carbs. have a tendency to frost up in colder climates a good high rise for the RPM range of the engine is a better choice for the street in my opinion. If your running it at the track there are much better intakes you can run for power! You also had a 390 crank put into a 352 block you told me that yesterday! Tell these guys just exactly what your machinist did!!

Ill be off here for a few days!!, But I can tell fire birds is one guy to talk to By the little he said!! He knows F.E. valve train geometry (listen to him) : Gotta go jester
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Old 03-08-2012, 09:28 PM
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Because you installed larger than stock valves and the cam has a good bit of overlap you must check valve to piston clearance and all potential valvetrain interference, on this build.
You cannot assume anything on these Ford Big block builds.
Its never a bolt in with this motor.
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Old 03-09-2012, 12:33 AM
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352? Maybe Not!

Since this was brought up you should click on this: http://www.mre-books.com/interchange/interchange11.html And to learn more about FE's you should buy the book.As per this discussion http://www.network54.com/Forum/74182...borderline____ Comp Cams recommended a max of .300" lift with non-adjustable rockers multiply that times the 1.76 rocker arm ratio and you get .528" lift.You must keep in mind that FE Fords produce a ton of torque you don't need to twist them up like a SBC to make power so the cam and intake I recommended will give you low end and strong mid range power,your biggest issue at the strip will be hooking up that torque to the pavement.

Last edited by JeffB; 03-09-2012 at 12:53 AM.
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Old 03-09-2012, 08:04 AM
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ok thanks guys so since my block was bored .050 over with a 390 crank is it a 390? i looked into those street master intakes and i found one on ebay. and do you guys think i should go with my 750 vac. adv. or a 650 cfm carb? i think i will go with that comp cam. thank you
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Old 03-09-2012, 08:11 AM
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hey f-bird when you said 750dp do you mean double pumper? thanks
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Old 03-09-2012, 08:29 AM
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Quote:
Originally Posted by 64 fairlane 500
hey f-bird when you said 750dp do you mean double pumper? thanks
yes get a good used 650-700-750 double pump carb to rebuild and upgrade with the Holley-Proform HP750 carb body and rear jet extensions . more flow+ adjustable air bleeds + down leg boosters +more power. very responsive.

Just right for your 4 speed 390FE fairlane w the performer rpm intake.
A sweet 750HP carb at a fraction of the price of new.

i do not know the ultimate practical realiable valve lift limit with the stock non adjsutable FE valvetrain. It will be +/- .500". Comp cams will advise.
The pushrod length has to be just right.

Don;t get all wrapped up in excessive valve lift for this one.
+/-.500" lift is just right.
Its the in - ex .050" duration and cam LSA that matters.

The cam I recomended will be about right. Comp can advise, call them first.

CID (V8) ='s bore x bore x stroke x 3.1416 x2
compression ratio http://www.wheelspin.net/calc/calc2.html

Last edited by F-BIRD'88; 03-09-2012 at 08:54 AM.
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