The Ford Barn

OLD...BILL · 10-23-2011, 06:08 PM

Quote:

Originally Posted by Ol' Ron

I like the 425 Potvin, It will make a great deal of power. It's about the best cam for doing so. It requires a great deal of spring pressure and is best made form a steel billet. It uses a standard flat tappet. The cam requires a hi idle to prevent lifter/lobe failure. Unfortunately getting 200hp might not be possable. I suggest you go to a roller cam.

OL'RON; WHILE YOU HAVE YOUR CAM SPECS, OUT WILL YOU PLEASE POST ON TWO HOWARDS I HAVE, ONE IS M-8, I'VE BEEN TOLD ITS A GOOD, MILD STREET CAM ?? THE OTHER IS M-12, WITH 360 LIFT ?? HOPE ITS A GOOD PULLER, FOR A HEAVE CAR... 39 FORDOR?? YOUR INPUT PLEASE,...,ALSO I HAVE AN UNKNOWN, CAM WITH FLATS ON TOP THE LOBES, ABOUT 1/4" WIDE,IT WILL A GOOD LIFT AS THE HEAL OF THE LOBE IS GROUND TO THE SHAFT, LIKE THE WEBER F-6,THAT WAS PICTURED LAST WEEK ... AGAIN ... THANKS .... OLD....BILL

Flathead · 10-23-2011, 06:32 PM

The Potvin 425 is a great cam. I have drag raced with one, but never tried one for the street. A strong motor for the street is not all about the HP. You want a broad power band and good torque for the best drivability.

I have run a 296 motor with a 400jr on the street with good results, I'm sure there are other choices too.

The 425 potvin will pull to at least 7000 rpm in the dragster, but I wouldn't want to be doing that over and over in a street car. That is a lot of piston speed with a long stroke flatty.

flatheadz-forever · 10-23-2011, 07:41 PM

what do you guys think I should run if I want a real lopey idle that pulls hard upto bout 5500

Pete · 10-23-2011, 09:53 PM

Quote:

Originally Posted by flatheadz-forever

what do you guys think i should run if i want a real lopey idle that pulls hard upto bout 5500

1007b

JWL · 10-24-2011, 05:59 AM

Yes! 1007B.

Highboy34 · 10-24-2011, 10:58 AM

Sponsored Links (Register now to hide all advertisements)

I should know the answer, but i don't. Who makes the 1007B?

OLD...BILL · 10-24-2011, 01:21 PM

"ISKY" And Pete grinds em on your stock cam, you send him.... OLD...BILL

flatheadz-forever · 10-24-2011, 03:55 PM

what are the specs on that cam and does the 1007b have a lopy'er idle than the 400jr

Pete · 10-24-2011, 04:44 PM

Quote:

Originally Posted by flatheadz-forever

what are the specs on that cam and does the 1007b have a lopy'er idle than the 400jr

In 20/55
Ex 60/18
Lift .360
255 dur
Rate of lift .008 per degree sq.
Lobe sepearation 112
In .011 Ex .013
Lopey idle

Whether the idle is more lopey than the 400jr is purely subjective.

Ol' Ron · 10-24-2011, 05:30 PM

Yes the 1007B is a good cam, but i Prefer the L-100. Now rather than start an argument I suggest you build two engines exactly alike except for the two cams and pick the one you like best. The L-100 has 246*@.050 intake and 235* lift @.050" exhausr. Grose lift is .375 Clearance .016.

M-12 30/67 int. 23/71 ex .360" Lift. This is calssed as a full race drag cam, should idle lopy

M-8 23/57 intake 11/70 ex .328" lift .014.016 clearance This cam is classed as a 2/3. I've never tun the M12 so can't comment on it. I have run the M-8 and feel this cam has the potential of giving excellent fuel mileage is an econo engine and is slated to be used after I run the tests with the EAB cam.

Choosing a cam for street is a crap shoot and is ony a personal choice. I have a 1007B in KGS engine and the idle is very nice with alittle lobe. Most of my engines have the L-100 and is the cam we;re using in our mileage tests. More on this later.
Good luck

flatheadz-forever · 10-24-2011, 06:41 PM

ok so what are your guys opinions on main caps I was wondering if having all three main caps billet would be over kill.

flatjack9 · 10-24-2011, 07:21 PM

Stock caps are more than adequate for a hot street engine.

Pete · 10-24-2011, 07:31 PM

Quote:

Originally Posted by flatheadz-forever

ok so what are your guys opinions on main caps I was wondering if having all three main caps billet would be over kill.

Either steel caps or straps....Your choice.
Straps are cheaper...You don't have to align bore...Some of the 100% nitro drag engines only use straps.

Ol' Ron · 10-24-2011, 08:16 PM

Yup!

Ol' Ron · 10-24-2011, 08:20 PM

Pete
I have a potvin 400, never realized how close it was to the 425. How does it run in compairison to the 425?. What's the application? New, I think I might sell it>

flatheadz-forever · 10-24-2011, 08:29 PM

ron Id be intrested

Pete · 10-24-2011, 10:54 PM

Quote:

Originally Posted by Ol' Ron

Pete
I have a potvin 400, never realized how close it was to the 425. How does it run in compairison to the 425?. What's the application? New, I think I might sell it>

The 400 is bigger than the 425...NO midrange.
Good race boat or Bonneville cam.

Ol' Ron · 10-25-2011, 09:44 AM

My friend Dick from Cape cod runs the 425 in his 345ci Flathead dragster. can't believe it's still in one piece. You should hear this thing!!!

OLD...BILL · 10-25-2011, 01:38 PM

NO OFFENSE GUYS; ..but this engine your building and the model A peeckup your going to put it in, if you get it to hook-up to ground (road).... you will "corkscrew" your frame, don't ask how I know this.... and ... OLD....BILL opens another can of worms .... lets be safe out there .... yes; I do care... O.B.

Ol' Ron · 10-25-2011, 02:08 PM

Thanks Bill, we needed that.

10-23-2011, 06:32 PM	#22
Flathead Senior Member Join Date: May 2010 Location: Southern Maine Posts: 1,502	Re: Flathead Questions and concerns!!!! The Potvin 425 is a great cam. I have drag raced with one, but never tried one for the street. A strong motor for the street is not all about the HP. You want a broad power band and good torque for the best drivability. I have run a 296 motor with a 400jr on the street with good results, I'm sure there are other choices too. The 425 potvin will pull to at least 7000 rpm in the dragster, but I wouldn't want to be doing that over and over in a street car. That is a lot of piston speed with a long stroke flatty.

10-23-2011, 07:41 PM	#23
flatheadz-forever Senior Member Join Date: Sep 2011 Location: New Jersey Posts: 156	Re: Flathead Questions and concerns!!!! what do you guys think I should run if I want a real lopey idle that pulls hard upto bout 5500

10-24-2011, 05:59 AM	#25
JWL Member Emeritus Join Date: May 2010 Location: Fitzgerald, Georgia Posts: 2,204	Re: Flathead Questions and concerns!!!! Yes! 1007B.

10-24-2011, 10:58 AM	#26
Highboy34 Senior Member Join Date: May 2010 Location: Boerne, TX Posts: 142	Re: Flathead Questions and concerns!!!! Sponsored Links (Register now to hide all advertisements) I should know the answer, but i don't. Who makes the 1007B?

10-24-2011, 01:21 PM	#27
OLD...BILL Senior Member Join Date: May 2010 Location: Northern California,coast Posts: 552	Re: Flathead Questions and concerns!!!! "ISKY" And Pete grinds em on your stock cam, you send him.... OLD...BILL

10-24-2011, 03:55 PM	#28
flatheadz-forever Senior Member Join Date: Sep 2011 Location: New Jersey Posts: 156	Re: Flathead Questions and concerns!!!! what are the specs on that cam and does the 1007b have a lopy'er idle than the 400jr

10-24-2011, 05:30 PM	#30
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,889	Re: Flathead Questions and concerns!!!! Yes the 1007B is a good cam, but i Prefer the L-100. Now rather than start an argument I suggest you build two engines exactly alike except for the two cams and pick the one you like best. The L-100 has 246@.050 intake and 235 lift @.050" exhausr. Grose lift is .375 Clearance .016. M-12 30/67 int. 23/71 ex .360" Lift. This is calssed as a full race drag cam, should idle lopy M-8 23/57 intake 11/70 ex .328" lift .014.016 clearance This cam is classed as a 2/3. I've never tun the M12 so can't comment on it. I have run the M-8 and feel this cam has the potential of giving excellent fuel mileage is an econo engine and is slated to be used after I run the tests with the EAB cam. Choosing a cam for street is a crap shoot and is ony a personal choice. I have a 1007B in KGS engine and the idle is very nice with alittle lobe. Most of my engines have the L-100 and is the cam we;re using in our mileage tests. More on this later. Good luck

10-24-2011, 06:41 PM	#31
flatheadz-forever Senior Member Join Date: Sep 2011 Location: New Jersey Posts: 156	Re: Flathead Questions and concerns!!!! ok so what are your guys opinions on main caps I was wondering if having all three main caps billet would be over kill.

10-24-2011, 07:21 PM	#32
flatjack9 Senior Member Join Date: May 2010 Location: Oshkosh, Wi Posts: 4,535	Re: Flathead Questions and concerns!!!! Stock caps are more than adequate for a hot street engine.

10-24-2011, 08:16 PM	#34
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,889	Re: Flathead Questions and concerns!!!! Yup!

10-24-2011, 08:20 PM	#35
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,889	Re: Flathead Questions and concerns!!!! Pete I have a potvin 400, never realized how close it was to the 425. How does it run in compairison to the 425?. What's the application? New, I think I might sell it>

10-24-2011, 08:29 PM	#36
flatheadz-forever Senior Member Join Date: Sep 2011 Location: New Jersey Posts: 156	Re: Flathead Questions and concerns!!!! ron Id be intrested

10-25-2011, 09:44 AM	#38
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,889	Re: Flathead Questions and concerns!!!! My friend Dick from Cape cod runs the 425 in his 345ci Flathead dragster. can't believe it's still in one piece. You should hear this thing!!!

10-25-2011, 01:38 PM	#39
OLD...BILL Senior Member Join Date: May 2010 Location: Northern California,coast Posts: 552	Re: Flathead Questions and concerns!!!! NO OFFENSE GUYS; ..but this engine your building and the model A peeckup your going to put it in, if you get it to hook-up to ground (road).... you will "corkscrew" your frame, don't ask how I know this.... and ... OLD....BILL opens another can of worms .... lets be safe out there .... yes; I do care... O.B.

10-25-2011, 02:08 PM	#40
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,889	Re: Flathead Questions and concerns!!!! Thanks Bill, we needed that.