Help: Builing a Street 408

[donraye]

Originally Posted by bobcowan

>> I have a perfectly functioning 10.4" OEM type clutch and pressure plate set-up with only 1,700 miles on it. I need to know if it will stand up to the 500+ crank HP of the 408 or not. <<

I doubt it. Because the car is so light, and you're not running slicks, you really don't need a racing clutch. But the stock one won't last.

My engine puts 470hp to the pavement. I have run it down the 1/4 miles a few times, with slicks. I run it on the road course fairly often, and I'm not afraid to beat on it on the street (no racing).

My clutch is a Centerforce dual friction. After two years of abuse, it looks surprisingly good. I'm installing another one just like it.

I suppose I can not simply use a new clutch dics from Centerline with my OEM pressure plate. Will I need the whole set-up from them or would one of their disc work with the existing pressure plate? (I am dreaming I suppose to think I could get away with that at just $90!).
D.

[bobcowan]

Originally Posted by donraye

I suppose I can not simply use a new clutch dics from Centerline with my OEM pressure plate. Will I need the whole set-up from them or would one of their disc work with the existing pressure plate? (I am dreaming I suppose to think I could get away with that at just $90!).
D.

I'm sure you could. I don't see why you couldn't use a Centerforce disc with a stock pressure plate. I don't know how long it will last, but it would work.


The Centerforce PP is made by Valero - they make a lot of clutch parts for aftermarket companies. But Centerforce adds the weights to increase clamping force as the rpm's climb; that's the real "magic".

[donraye]

Originally Posted by bobcowan

I'm sure you could. I don't see why you couldn't use a Centerforce disc with a stock pressure plate. I don't know how long it will last, but it would work.

The Centerforce PP is made by Valero - they make a lot of clutch parts for aftermarket companies. But Centerforce adds the weights to increase clamping force as the rpm's climb; that's the real "magic".

Want to buy a new Centerforce complete clutch kit for the 408. Problem is I do not know exactly what to buy for sure. As near as I can figure the clutch I have is a Sachs OEM replacement of some sort but there are no mumbers on it that make any sense with what I can find online in parts sources.
I know the disc says Sachs and is a 10.5" disc. the pressure plate is a 10.5" God knows what and the main number on it it is a huge cast in "MF265". When I try to search it online all I come up with is a Massey Furgerson Tractor part! Know that isn't right but damned if I know what it is? It does say Made in Mexico on the perimeter of it but that is no real help. It seems to me it is NOT the correct OEM clutch for the block I have/had, but if worked fine! So I am trying to find a direct replacemnt for it in a much more robust form like the "Centerforce Dual Force" line.
So... I think (?) I can use the Centerforce model # DF021057 See it at:
( http://store.summitracing.com/partde...5&autoview=sku ) Which is actually supposed to be for a 1995 5.8 liter/351 Windsor Mustang Cobra "R". It is the only one I can find for a 351 Windsor that is 10.5" (like the one I have now is) and will work with my new billit steel SFI flywheel which will only take a 10'5" MAX clutch size (not an 11" like most of the 351 clutches I see out there). And I think it will be compatible with my T5 Z spec.
Are there any reasons anyone can think of that this model clutch will not work for me even though it is probably not OEM for this engine block butit is the same disc size, shaft size, 10 spline, for 351 windsor, etc. The photo of it looks right and the bolt hole placements, etc seem right in the photos, but I'm no clutch expert.
All the other 351 windsor clutches I can find are either 11" (won't work with my flywheel), or the 10" ones that are all for 289/302. So this seem to be the correct one for my application being it is for a 351W and is a 10 spline with the correct size input shaft, etc.
Any more educated thoughts out there?
If not, I think I will buy it from Summit because if it turns out it is wrong they make it pretty easy to return. If I get it and carefully compare it to the unit I am replacing and all seems the same: outer dimensions, holes line up, same overall thickness of the assembly, splines fit right, etc. then it will be good to go. Right?
D.

[392cobra]

Originally Posted by bobcowan

The Centerforce PP is made by Valero - they make a lot of clutch parts for aftermarket companies. But Centerforce adds the weights to increase clamping force as the rpm's climb; that's the real "magic".

I have the Centerforce clutch behind a BBC in a '67 RS/SS.
It does clamp,just like I want and need.

The down side is it is SLOW to release at rpm's above 6k.If you're looking to shift fast,get rid of the weights they add to them.

[donraye]

Originally Posted by 392cobra

I have the Centerforce clutch behind a BBC in a '67 RS/SS.
It does clamp,just like I want and need.

The down side is it is SLOW to release at rpm's above 6k.If you're looking to shift fast,get rid of the weights they add to them.

My understanding from research and talking to other Centerforce users is that the weights are the reason the Centerforce is able to provide 90% more clamping power than OEM type units. If you remove them then I think you might as well just use one of their disc with your OEM type pressure plate and save the $ spent on their "weighted pressure plate technology".
Also: I'm running a hyd. roller cam and I doubt that I will ever fell the need shift fastly above the 6,000 RPM level, as my cam is pretty much "done" it's best by 6,000 RPM anyway. I have no desire to "speed shift" at all much less at or above 6,000. There are no racing intentions just a strong pulling street performance engine with no powershifting/speedshifting desires.
Thanks for the good input but I think for my needs the clutch will shift as quickly as I will ask it to on all but perhaps the rarest of occasions.
I do however truly appreciate your reply and your giving me some much needed education on the subject.
Thanks, Don
P.S. That Lone Star looks great and my favorite color (next to the more unique "Grabber Orange" anyway). I really like their LS427 Cobras and think they are among the very best out there. A lot of folks don't know about them but they should. Comfortable too, plus they make a really nice and afordable removable hard top for them as an option. My next one (if there is a next one) might be a Lone Star kit. They have a great 7 day home build program also. You made a great choice!
Really like them.