Looking at speedways adapter kit and it says to use a 49-53 merc b & b pressure plate with a 10" flathead Ford clutch disc. After not finding much when googling for the recommended pressure plate I got curious. Why couldn't I just drill and tap the flywheel to use a regular flathead Ford pressure plate? Be more work but they're all over the Internet for sale
The splines on the transmission input shaft are different. 1 3/8"-10 on the '48 and earlier transmission; 1"-10 on later disc. Don't quote me on the spline count.
Yeah that's why they said use the Ford disc with the merc pressure plate. Just wondering if I can just redrill flywheel and use a complete early Ford clutch
It could probably be done. Like everything else, it's cheaper and usually better if you can use a proper combination of stock parts. If the Merc pressure plates become unavailable, you may have to resort to machining and determining compatible components. Redrilling a flywheel at home on your drill press is not recommended.
you can totally do that, redrill the flywheel that is. The reason to use the 49 to 53 merc pressure plate, is because it bolts directly on to the Chevy flywheel, since they have the same bolt pattern. That being said, as long as the pressure plate clears the adapter you can use any pressure plate that clears. You would need to take the flywheel and pressure plate to a machine shop to have the pattern drilled for that pressure plate. I've had old aftermarket race flywheels that had both patterns drilled from the factory that way.
I have used the Merc pressure plate now twice because it bolts up. Machine shops around here take ages to do anything, including something as simple as drilling a flywheel. Last time I called Wilcap directly and they sent me one.
i think it is because maybe the flathead transmission to small block chevy adaptor can ONLY use the smaller chevrolet manual flywheel 168 tooth large 11'' 153 tooth flywheel small upto 10,5'' ? ergo you can only run a 10 inch max friction disc on a 37 up flathead transmission as the 11'' pressure plate hits the adaptor so you have to run the small chevy flywheel these are drilled 6 holes 60 degrees apart the 8ba mercury pressure plate SHARES THESE DRILLINGs - bolts straight on unlike the ford pressure plates and flywheels which have 3 close paired drillings!! YOU NEED to use a flat head pressure plate as the distance of the throw out bearing to pressure plate contact surface point remains stock flathead - and not for example a later style pressure plate that is multi fingered so 2 its only the 10 inch friction disc with the spline count of the flathead input shaft that will fit the gearbox its only the flathead mercury 10 inch pressure plate that fits the small cevy flywheel its only the 10.5'' 153 tooth flywheel that fits the adapptor something like that TAKE HEED there is a 9.5'' clutch set that fits a mercury flywheel and they might be close. so dont buy the wrong one. and no a later 11'' 60 on 6 borg and beck style pressure plate will not fit as the rivet heads on the flat springs will touch the inside edge of either a half bell or a 59a - i.e. you wont be able to bolt on a half bell to an 8ba as there will be 5-6mm 1/4'' in the way = impossible. the 10 inch brings the rivets inboard 1/2'' and it goes in thats IF you want to keep the cross shaft and stock clutch pedal -typically just bough an 8ba with a t5 from a running car - 41 frd thinking it had a stock cross shafted clutch and its the later chevy fork style with an hydraulic slave, so now have to completely re-do both the brake and clutch pedals to get the clutch master in - as its rhd!!! pah!!
Mine uses the 168 tooth FW Had a merc PP and correct gm flywheel. I pulled it out of a 63 c10 with a 230 Im using the old style 3 bolt starter.
does the clutch function i mean the transmissions cross shaft and double finger- acting upon the stock flathead throw out bearing and the distance between it and the contact face of the pressure plate do the two fingers from the cross shaft track a chord in a straight lineright to left as it looks like your cross shaft take off for the clutch pedal is too mar forwards - anti clockwise and not projecting up and back a smidgers
I’m just putting this together. Going by the info at Speedway and here. https://content.speedwaymotors.com/DigitalAssets/assets/testing/7200392_INS_2021_1.pdf Using the merc clutch, PP and TO the set up should work just fine
I have the starter and throw out bearing. Kit calls for the larger flywheel and all I have is a small one from a 57 Chevy 283. So I'll need to buy a flywheel (not a big deal). My issue is not finding anyone selling one new or reman. And can get the Ford equivalent new and reman. 10" clutch is to clear adapter and they specify the merc pp because of the bolt pattern. If they're the same height I honestly would prefer the redrill path as replacements would be easier
The CORRECT Borg and Beck 9 spring pressure plate for this hookup is Model 1310, 49-50 and early 51 Mercury. Disc is standard Ford 10” with 1-3/8” 10 spline hub. Other B&B’s may bolt on and work, but this is the expert’s choice. Not me, Fort Wayne Clutch. Talk to Lou! The cores are hard to find. If Ft Wayne has them, the core charge is $90! If you have a clutch rebuilder close by you might get lucky and save some bucks. You also need a new pilot bearing from Speedway or WILCAP to mate the Ford input shaft to the Chev crank.
Be prepared, they are not cheap by any stretch. Here’s the pilot bushing. https://www.speedwaymotors.com/Replacement-Pilot-Bushing-Chevy-Engine-to-Ford-Trans,39106.html
FT Wayne clutch is the way to go. You used to be able to get the Merc pressure plates from Wilcap a few years ago. I've bought several from them over the years, but I've heard that they have sold to another company and they don't want to sell you just a pressure plate anymore, they want to sell you a whole kit. Not sure if its true but that's what I heard.
hello, please help me here, do you use the 168 tooth fly wheel or the 153 fly wheel? i'm doing this conversion right now and i keep getting conflicting opinions on which fly wheel to use, thanks you ,Will.
hi Jason, you happen to know what fly wheel to use would you? a 168 tooth or a 153 tooth chevy fly wheel? thats my only hold back to getting this thing in the car !!!!lol
Might help to know exactly what other parts you have, eh? There are a few different things discussed in this thread. What adapter do you have? what transmission? what clutch are you planning to use? The 3 bolt starter that they mention only works with the 168 tooth flywheel, if that's any help.
I have a part number for the right flywheel for a two-piece rear main but he has a one piece rear main small block. I’m finding 1 piece rear main 168 tooth but not much information on the bolt circle pattern for the clutch. I guess we also need to know what clutch you are using. Borg and Beck Mercury pressure plate 49-51 will bolt up to the flywheel below. for reference, here’s the flywheel I used for a two piece rear main. https://www.jegs.com/i/JEGS+Performance+Products/555/601205/10002/-1
hi dan i was going to use the '49 to '50 merc pressure plate and the disc that goes with it. if i have to i'll have the flywheel drilled and tapped because i know they are different bolt pattern to the crank.
I had to buy this for my 350 with one piece seal, external balanced, B&B pattern. My free rebuilt engine had no flywheel. Probably cheaper to redrill yours. https://www.speedwaymotors.com/Speedmaster-1-229-011-168-Tooth-Billet-Flywheel-Chevy-350,323449.html
168 tooth is the one to use. If you have any questions on doing this just PM Me, ill send you my cell number and you can call or text me.
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