New member-looking to launch 4 spd Ford w/ Cals/mono/ranchos

[Steve Vardion]

Hello - I'm a new member...I built a 1970 Mercury Cyclone with a 564 CID NA motor, making just about 800 FWHP, wide ratio toploader (2.78) with 4.11 with 28.5 drag slicks fresh ~ one year old with about 10 passes...locker diff...2800# PP (long) w/ sintered metal clutch...light flywheel...last few years, I just built a nasty 514...460-based motor (solid roller 286 @ .050 110 lsa .720 lift)...12.65 CR...victor & 2-circuit dommy...the usual stuff...cheap eagle crank & H-beams...ported iron heads flowing 350/240...it ran 132.8 mph but only 10.90 due to stock rear susp with Cals only netting a 1.70 short time...

It dropped a manley SD valve and took out block & cylinder head...no more roller cam springs for me...

I built a short stroke 564 (4.3 stroke) (new A-block), long 6.8 Eagle H-beams with 2000 bolts...Scat forged steel...internal balanced to within 1g...loose PTW clearance at .0053"...nasty solid flat tappet 286 @ .050 with a roller-like 198 at .200 lift, 110 lsa with .730 lift at valve, accounting for lash...1.8 Crower roller rockers...Victor & 1150 2-circuit and TFS streets ported (myself)...6al set at 7000 with light at 6800...I expect 135 mph maybe 136, but am trying to learn how to launch it...

I went with 225# split monos, Cals (lower hole) and Rancho 9000's...I set the cals at one turn preload (101 usual tips)...Ranchos set in the middle...

Question: I was revving it to about 4000 rpm, letting out clutch fast, bogging it a little and then nailing it...Can I just dump the pressure plate at 5000, or should I be bogging it a little...the slicks are only 10.5 wide...I cannot imaging it'll wheelie much...any tips on how to adjust this set-up and launch it would be appreciated. I see alot of you guys run fast leaf spring cars with monos...

It has a Denny's with solid U-joints, 31 spline mosres with daytona bearing Moser carrier with solid pinion bearing spacer...it should hold up...

I am running it a New England Dragway this Sept. Thanks

Steve Vardion

[John_Heard]

Steve there's a few clutch guys on here, hopefully they'll see your post and give you some tips on getting rid of the bog.

[clutchdude]

Well i will say first thing is that you will want alot of weight transfer....that is number 1 goal for me. Next does that clutch have a centrifugal assist? If it does your in good shape.....if not your like me. I get away with a non adjustable clutch (diaphragm street pressure plate) by using alot of first gear 3.28 and small block thats makes good torque. And next is F/W weight, i can leave at a fairly low rpm (5000) and not bog the motor because the f/w is heavy enough to get me off the line. So i would say for me what im shooting for is controlling wheel speed by F/W weight, first gear ratio and tire pressure with a car that will transfer weight real good.

My car is 51/49 on weight balance which helps alot. I think on your car your going to need a adjustable setup. Also there are the ignition boxes that have adjustable timing maps...i have thought of using one everytime i go to a crappy track...lol

P.S. look at the video of my car and you see that with all that first gear i actually put the car in second while wheels are up..and you can hear the tell tale signs at each gear change that my clutch does not slip on gear changes....Good Luck and keep us informed of your progress.
Jim

[sc68z28]

I think on your car your going to need a adjustable setup.
Jim

I agree with Jim, go with an adjustable clutch, sure fixed mine.
Before I got the adjustable my car either bogged, blew the tires off, or broke something .

Now I can launch at 6400 rpm (peak HP) the clutch slips just enough to send me on my way without breaking, bogging or killing the tires.
I'm still tuning mine, but I think I'm real close now with consistant 1.38 60' times. OBTW that's almost 3/10s impovement over the old clutch.

My clutch is adjusted to about 1/3 your base pressure and has centrifugal assist, that's what allows the slip at launch then lock up down track.

Jim has made his car work very well, thats rare with a stick car, but he knows what he is doing. His combo is set just right, and works!

I run a 3.11:1 first, a with 4.11 rear gear, with a... http://www.advancedclutches.com/ 7" two disc, weighs 20 lbs including the flywheel.

For great info on most drag race stuff (chassis, engine, so on) right here is the place to be.
For clutch and stick trans info also go here... http://www.umtrnorth.com/forums/default.asp there's a clutch and tranny tech section, take a look around.

---Bill.

[Steve Vardion]

Thanks for the replies. I totally agree with you about an adjustable clutch; the problem is that I have spent just about enough on this for the year (I hate to think what the total amount is...) so \Ii don't want to drop the $750 or so for an adjustable set-up. This is primarily a street car with once-per-year drag racing at a track rental. I plan on serving as the "human adjustable PP" with the Ram long set-up...if I strap myself in tight enough with the 5-point set-up, and really concentrate on negating the accleration G(s) upon launch, focus on the relationship of my legs to the seat...I can somewhat ride the clutch and hopefully get one 1.5 short time...I added split-monos with 9000's so I should get some better action on the rear susp...I used to run a Centerforce dual friction which had (non-adjustable) centrifugal assist, but after about 30 launches, 3800# at 1.70 short time...the fiber came off the disc...I pushed the clutch in at the top of third at 7200 rpm and ...dust...as soon as I unclamped it, it exploded radially outwards from the rotational accleration...I couldn't even drive it back up onto the trailer...anyways - thanks again for the good avise. Steve

[clutchdude]

Well Steve i'm right there with ya...i just dont wanna spend the money, thats why i figured out how to make my Diaphragm setup work and work well i think. And yes i'm starting to look for a adjustable setup for my car, last time i went out was with the new split leaf mono's and qa1 shocks.....while it did not make my car much quicker...i now have consistency with my 60' all 5 runs were 1.374-1.382

I agree with you on slipping the clutch on the starting line...i have done it on accident on a night when i could not get the car to hook in 55 degree weather...lol

Now if you had a hydraulic setup there are ways to cushion the engagment And yes my car has a hydraulic setup in it

As for your street disc coming apart all you need to do is get steel backed linings, that will eliminate the linings from coming apart. Actually i have had my best 60' from a organic disc 1.301 and i still had the stock mono leafs on the car with junk CE shocks.

http://www.advancedclutch.com has steel backed organic clutch discs if you were looking for one if your pressure plate is still good?

Looking forward to your results with some more pics Jim

[Steve Vardion]

I obviously replaced the Centerforce with an all-metal 6-pad long style from RAM, with 2800# I believe. It holds in forth gear, and doesn't come apart at 7000, but it engages pretty solidly...I just plan to ride it a little...otherwise I'll either spin or break I suppose...thanks. Steve