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Clutch Size...does it matter?

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AlfaHealey

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I tried to search through threads but came up empty. I'm about to finally pull the trasmission from my '59 100-6 and need advice on replacing clutch. Healey has original engine but the transmission was changed to a center shift (not sure from which model). While I don't know what I will find when I open everything up, does it matter what size replacement clutch package I use...9", 9.5", 10"? What determines the limits? Is there a driving benefit to using a larger clutch assembly? Any recommendations on where to buy bearing, plate and disk? Thanks much, any advice appreciated.
 
No I do not see any problems relating to the clutch size in your case. Simply replace with the size you find installed on the car. Just about any of the parts suppliers carry clutch kits for all models of the cars.--Fwiw-Keoke
 
It is a curiosity to me why some will reduce the weight of the fly wheel and then put in a larger, heavier size clutch. It's not the weight of the clutch itself but it does add momentum to over come.
 
The inertia of the flywheel/clutch combination depends greatly on where the weight is located. The further out from the center of the flywheel, the more effect a given weight has. Weight that is located closer to the center, such as the clutch, has less effect on inertia.

For an example, see the attached pic of my new flywheel which has major weight reduction near the outer edges.
D
 

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Dave, I assume that is a Denis Welch Flywheel. Are you happy with the performance? Still have sufficient low end torque? How much lighter is it? Bill Bolton took 4 lbs off of mine.

Lin
1960 BT7 in restoration
1959 Bugeye
 
Seems to me that all the performance enhancement opportunities should be evaluated in relation to how you intend to drive. Stock clutch, flywheel, etc. should be just fine for neighborhood cruising.
 
Cutlass said:
Seems to me that all the performance enhancement opportunities should be evaluated in relation to how you intend to drive. Stock clutch, flywheel, etc. should be just fine for neighborhood cruising.
Click to expand...




Yep but these days it just might depend on what type neighborhood you find yourself in!---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
Hi Lin,
Yes, it's a DW flywheel. I don't know how much your flywheel weighs to begin with, so I don't know how much it now weighs. Different models had different weights.

A stock Hundred Four flywheel weighs 40 pounds. Mine had been reduced to 30, no noticeable difference. The DW wheel weighs 14 pounds & 26 pounds total with the clutch.

I don't expect it to hurt the driveability much, but it will be different. Remember, this is a very long stroke engine, 4 3/8" to be exact.

I'm raising the power peak rpm from 3,800 to 5,400 rpm. With the compression ratio increase from 7.5 to 9.7, it will still have more torque at 3,000 than the original engine.

The original engines had crankshaft problems above 5,000 rpm. I'm using a DW billet crankshaft & Carillo style rods to keep things together at the much higher rpm that it will be running. With the ATI friction type front damper, DW says that the combination will reliably turn 6,500 with ease.

A truck engine no longer. Haven't got it all together yet so I can't say how the combination will work but I expect it to be pretty good. Not intended for neighborhood cruising.
D
 
Well Dave, sounds like It will be OK even if you accidentally do get caught in a baaad Neighborhood.---Keoke- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
 
Just where are you guys driving these cars? 6500 rpm? Just hope you don't tangle with the SUVs and 18 wheelers and distracted drivers on cell phones. I look at that steering box, connected to the spear pointed directly at my chest, with nothing more than a few inches of aluminum between it and a five thousand pound pile driver coming the other way. I love driving these cars, and will continue to do so, but carefully, very carefully. I do remember that there are no padded dashes or air bags. Now outfitting one of these babies for the track, with appropriate roll cages, fuel cells, trained drivers all around, that's a different story. Maybe my work as a traffic judge and lawyer who has seen too many needless traffic deaths and injuried over 27 years makes me a bit conservative. One of my favorite, and common excuses folks give for going over 100 mph on our crowded freeways is that they "just weren't paying attention to their speed." Does that terrify you as much as it does me? Make 'em as powerful as you want, but be careful when using all those extra ponies.
 
Well Judge, I'm gonna tell you the only way to know the jag is at the correct legal speed and not doing 100 MPH on the freeway is if you set the speed control on. Your job is like working in an aircraft repair and overhaul operation it looks like all the airplanes are falling out of the sky. About those "Trained Drivers" did you see the Indy 500? In closing I might add we may like performance but we are not stupid--Fwiw--Keoke
 
---Just where are you guys driving these cars? ----
Definitely NOT on the freeways. Lots of winding mountain roads around here. With enough acceleration, you can get well over 100 on the short straight stretches. Police are too busy watching the freeways to bother with the back roads. You can go very fast safely IF you use good sense, pay very close attention, & are experienced. Defensive driving doesn't necessarily mean going slow. A good bit of motorcycle track time, the ultimate in defensive driving, which is very good training for cars. Been doing it for many years, motorcycles & cars. Never even had a close call. I'd knock on wood, but everything seems to be synthetic nowdays.
D
 
Dave,
Sounds pretty cool. Keep us posted on the progress! What did yo do with the cam?
Lin
1960 BT7 in restoration
1959 Bugeye
 
Alfa Healey,

I have a definate recommendation. Go to a BJ8 setup with the diaphram pressure plate. You will be buying a clutch, pressure plate anyway. This means you need to mod your flywheel to change the dowel locations. Better yet exchange your 100/6 style flywheel with a lightened BJ8 version from Bill Bolton. Also do the rear crank seal while your in there.
Here is your shopping list:
-BJ8 lightened flywheel from Bill (or mod your existing)
-BJ8 clutch plate
-BJ8 diaphram pressure plate
-BJ8 Throwout bearing
-pilot bushing (use axle grease trick to extract existing)
-Rear engine crank seal
-possible rear tranny rubber bushes (ususlly dry rotted)

You will have a much better clutch setup for a modest increase in price.
rear_oil_seal.JPG

light_bj8_fw.JPG

pp_on.JPG
 
Lin said:
Dave,
What did yo do with the cam?
Lin
Click to expand...
Hi Lin,
I'm using the DWR-1 cam, 268 degrees duration. The original cam is 230 degrees. Attached a pic of the adjustable cam sprocket & cover.
D
 

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Bill had one BJ8 left last November. He had lots of the other ones. He has them made up in batches due to the machining necessary. I was thinking about it but decided to stay stock. He rebuilt my trans so it would have been easy to do it while everyting was apart. But.....
No regrets.
TH
 
Good luck, Dave. Do you teach your children that it's ok to set your own laws? I guess the speed laws are just for those who are not as good a driver as you. Don't mean to be too preachy here, just been to too many children's funerals. We have winding mountain roads in Georgia, too. Lots of motorcycle riders are killed there, taking innocent motorists with them, every year.
 
Cutlass said:
Good luck, Dave. Do you teach your children that it's ok to set your own laws? I guess the speed laws are just for those who are not as good a driver as you. Don't mean to be too preachy here, just been to too many children's funerals. We have winding mountain roads in Georgia, too. Lots of motorcycle riders are killed there, taking innocent motorists with them, every year.
Click to expand...
---- i believe the problem with the speed limit laws draws on the fact that not enough is done to teach/train the "inept" drivers how to drive correctly but rather penalizes the drivers that do. the inept are the ones that couse the vast majority of the problems/accidents, i also think what we should do is allow anyone that applies for a driver license be put in a formular-1 car at daytona with at least 4-5 hundred people at a time in a race, no matter how long it takes, the last 10 survivors would then be able to attain their license, i know "dave" would be one of them! and oh yes i
can tell that you never ever in your entire life have gone over the speed limit!-right? never conversed on your cell phone while driving?, never "pinched" a red light? and never ever had a couple of cocktails before turning the ignition key,and always come to a full stop at all stop signs? etc,etc,check yourself! get the bad drivers off the roads,not the good ones. the good drivers should not have to accommodate the bad ones all be it the bad ones are obviously the vast majority! and ya i think that driving test should be mandatory every 4 years , just think of how much less traffic thered be! ah utopia! ill be back for my part 2 installment i godda get ready for traffic court. /bcforum/images/%%GRAEMLIN_URL%%/whistle.gif
 
Cutlass said:
Good luck, Dave. Do you teach your children that it's ok to set your own laws?
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My "children" are all over 40 years old. I don't teach them much of anything, but I do learn a bit from them. One son in law races motorcycles along with his son, the other one trains horses.
D
 
Off original topic, but this speed thing is" interesting". Growing up in the UK during the '50's and '60's, there was of course far less traffic but a much greater pride in and respect for good driving. The driving test was significantly more difficult and for those who wished to go further there was the Institute of Advanced Motorists test, which involved skid pad testing and driving at high speeds on public roads. The benefits given to members were few except pride (and I suspect quite a bit of "Macho Ego"), but if you did get pulled over and sent before "da Judge" you simply pulled out your red IAM licence and you wree sent home with a wink and a thumbs up. The first time I tried this in the States I thought the Judge was going to have a heart attack and I was going to spend a life behind bars!!! I don't know about the rest of you but my BJ8 just doesn't sing until I'm almost blinded by polution! Cheers in Speed, David L
 
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