433 Isky vs 400Jr vs Schneider 284F, .425" lift......

Hi Pete,
tell us more about the new cam!
specs?

 

Here you go

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=140372817320

 

and also this one,

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=360224457033

 

Ain't no such thing. Any hot-hatch tuner worth his salt will dust your flathead every time...

You'll need a decent cooling system.




More importantly, you asked for first-hand advice and now you're ignoring it. The difference between 304" and 284" will be driveability and, most likely, reliability. The difference in power won't be significant enough to justify the cost, really. The level of prep beyond 284 goes up significantly and there's nothing left to rebuild if something goes pop.

 

As I said before . . . so how many flatheads have you built and ran? Listen to the folks on this board - there are many years of experience here, not just "bench racing".

You've gone to the 'Flathead Fortune Teller' . . . you choose what to believe from what she told you

 

Guys....

Please don't take me wrong!

I appreciate your assistance entirely and have now chosen to go with the 284 ci Flathead.

This is my first build but I sorta wanted to build something cool but as you guys have told me you need a compromise if you want to drive this thing so the 284ci in the end is the way to go!

I'll have to leave the 304ci build for my salt flat 'Belly Tanker'!!!

Flat Ernie: I know that a hot-hatch tuner will probably kill me but we're talkin' Flatheads..... Right?

HotRodMicky: You said that if I want good sound, to get a potvin 3/8".

Is this compomising with performance?

I'd love a nice sound and that a lot of the times are what Flatheads are about but I don't want to build a Flathead and throw a cam in it that doesn't match the performance of the rest of the motor. You with me???

What are the specs on the potvin 3/8"?

Also, For example, if I have .425" lift Edelbrock heads, add on .050" for the heads gasket, is it alright to go for a cam with .425" lift or is it safer to go with a cam with (for example: .415" lift) less lift???

Thanks.

HC.

 

The 3/8 has 280° and 0,375 lift.

That is a lot of duration/overlap.....

Overlap and compression is sound !


Your ports have to be big enough to "flow" the high lift 0,425.
Otherwise it will be only hard on the vavetrain.

Do you have the experience/tools to port the block ?


Did you mention what car the flathead will go in?
Weight?
Gearing?

Has a lot do with cam selection....

My suggestion buy a block , crank , heads, intake etc.
Then decide on a cam.


Michael

 

This motor will be going in an 'A' roadster.

That's why I stated earlier on that a bigger stroke and larger cam wouldn't be too sluggish in the 'A' roadster.

Don't have any experience porting but do have tools.

I'd love to go with a '39 3 speed but may go with a 5 speed!

Cam: would 284 and .415 or .420" lift be too much on this motor?

HC.

 

HevyCharger, I wouldn't go over 400 if it's for street ... use a 400 or similar not more...

I ran 25 000km, with a 3/4 isky and 6 PSi blower it was an easy drivable car (model A coupe) comparate to my 304ci and literio cam in the roadster...

Just my 2 cents...

 

That makes sense.

I take it that over 400 lift would be a bit too much but I don't mind if it's not an easy driver.

I mean, I don't mind giving it a bit and I don't mind the lopiness but there is somewhere where you have to stop just like what you guys are telling me.

So looking at the schneider range: 290F and .415" lift would be too much (???) so the 270F and .395" lift would do the job?

HC.

 

the 270F sounds good to me...

 

Hey Pete ,
let us know how your new cam will perform!
Do you stick in the 304?
Michael

 

I have sold my roadster last september... I'm now working on my coupe again, thinkin rebuilding the engine with a 284ci kit, and I get the compcam camshaft to go with, I really want to stay with the blower, a scot would be great! will see, I first have to build my garage to work in a good and warm place...

 

Hi Guys,

I run a 400JR on a 239 CI with a 39 3 speed gearbox on my 32 roadster, I think a 400JR are streetable on a light car and not so much on fatfender and other shoebox, I love this combo, it give lot of caracter a sound nicely, I did more than 25000 miles with it without troubles and never broken anythings except gears...

 

Except gears... LOL ;-)))))

 

hahah!

 

Yeah, what he said! I peeled the teeth off of my nice new 26 tooth original Zephyr gears one day in my 34 sedan . . . hasta la bye bye baby! Looked like somebody ate an ear of corn with one missing front tooth

 

433 is way too much cam for the street. That's what Whitey McDonald was running in his nitromethane drinking dragster the last time I checked. It needs more rpm to keep it running than you would want for a lopey idle at the drive-in. Lots of streetable engines run a 400jr.

 

Here ( or is it hear?) is my flatty with a 400jr

 

That sounds Sweet!!!

What are your specs???

HC.

 

It doesn't take a lot of power to frag a Ford 3 speed trans. I've built a few flatheads but I've built a bunch of Ford trannys. My last flatty was 286 ci, lots of port and head work, I used a Harmon-Collins 408 cam. Backed that one with a Cad- LaSalle 3 sp which got rid of the granny low gear of a Ford and you could not break it. Had a lope that drew a crowd, would pull 5800 easy. Had it in a 47 Merc-big car- was fun on the street. Would scare the beejeezus outa ya in a little roadster.
Sounds like your willing to spend some serious money on this build. Ever consider a roller cam from Tatom?

 

What are the specs on the HC 408 ???
Did you use adjustables lifters?
TIA
Michael

 

I'm interested in the specs of that thing too!!!

HC.

 

Look, it's a bit of a long term project so I am able to put a bit of money in this thing but I don't wanna go stupid!!

Wanna leave enough for the roadster.......

HC.

 

I am envious of your build plan. Mine is a little more sedate. I have a lively .040 over Ford 8ba. I did a mild port job, but I am running stock valves. Edmounds heads and a Fenton 2-2 intake and homemade headers. Also running the 400jr.....

 

Yeah, the roller cam IS big$$$$. Just checking to see if it were an option. I've seen it at his shop, nice set up. As far as specs and availability of the H&C 408, I'm not sure I can be a lot of help. A little story about how I came across it- I used to occasionally call flathead legends I'd read about like Kong Jackson, Barney Navarro and Bill Jenks and ask questions. These guys and others didn't know me from Adam but would take the time to talk flatheads with a perfect stranger. Anyway, in my quest for the best cam I could find I was referred to a fellow in Vancouver ,WA., Doug Lauzon, and was told to ask for his recommendation which would probably be 400 jr (and was) and to then casually mention the H&C 408. I had to promise I wouldn't tell him who I heard about it from. When I asked about the 408 I was greeted with stony silence, then a demand as to where I had heard about it. Doug was a drag racer and most of these guys were really secretive about their cams. Apparently Kenny Harmon gave Doug the master for the 408 before he passed away. After some wheedling and cajoling Doug agreed to grind me a 408 with my solemn promise not to tell anybody, and if asked specifically about the cam I was to tell folks it was a 400 jr. Doug was a great guy and built some pretty radical flatheads. He had a 330 inch motor, all 8 cylinders sleeved to get a large bore, that he fired up for me one day- that was the nastiest flatty I ever heard! Doug has since passed away and I have no idea what happened to the master.
To make a long story a little longer, I ran that 408 for about 5 years, no trouble. Used Johnson hollow adjustable lifters, Isky single springs, 1.6" backcut intakes, 1.5" exhaust, pretty extensive port work, stepped block relief, undercut Offy 425 heads to unshroud intake valve and modified combustion chambers to mimic Harley Davidson flathead dirt trackers.
I also adjusted all valves with a degree wheel to ensure valve timing was exactly the same between all cylinders. Believe it or not, it made a difference. Offy 4bbl intake port matched, ported Fenton headers. I miss that engine, it was a real labor of love. With the Cad LaSalle close ratio transthe thing would do 55 in low, 90 in 2nd, never had the nerve to hold it down in high but saw well over 100 a few times. I'm old now and don't drive like that anymore
The specs I do remember are .408 lift, 114* lsa. IIRC it was ground on a .904 base circle. I don't know the duration, but I do know the advertised (@.006) was longer than the 400 jr, it had a "gentler" lobe. You might try Delta Cam in Tacoma,WA to see if they can do one.
With all that said, I don't think you will go wrong with a Schneider grind. At the time i built that flattythe 408 was the best cam I'd run and had a good story behind it. I'd love to know how your project turns out.
Cheers from a long winded bastard

 

That's a great story '35!!!

Do I'm guessing it isn't gonna be cheap for a 408 either as they will probably have to grind it on order???

I'll definitely look into it though!

HC.

 

Now thats Funny!!!!!!!!!!

My wife thinks i am twisted when she catches me laughing in front of the computer. Ecspecially when she finds out i am on a Hot rod web site.

 

Bored and Stroked - that was for you
hahahhahahahahahahahhaah

 

I have the same affliction . . . without the laughter, it wouldn't be worth reading! Sometimes I just see somebody's avatar on the HAMB and laugh my ass off.