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MG TD TF 1500 - Flywheel lightweight

I need a recommendation for a source for a lightweight flywheel for my TD.
TIA,
Mort
Mort 50 TD

The flywheel is made by Brown&Gammons. The difficulty is sourcing the clutch, pressure plate and modified T/O bearing. Manley Ford now sells the kit:

http://www.freewebs.com/manley776/apps/photos/photo?photoid=197913268

Bob Grunau also sells a lightweight flywheel, but I have no details:

http://www.ttalk.info/Grunau.htm
J Barry

Mort,
I would think that any good machine shop/engine builder should be able to lighten yours properly.

Steve
Steve Wincze

Mort;
Somewhere there is a paper on lightening the flywheel.
Its by Bob Grunau.
I have three drawings I can send. They are dated 1/28/2014 so I have had them a while, but I remember seeing it recently.
It does appear his process utilizes the existing Pressure plate and TO bearing.

Jim B.
JA Benjamin

Mort

Bob Grunau's drawing for the lightening of a 7 1/4" TC / early TD flywheel can be found here http://www.mg-tabc.org/library/BG_flywheel.htm.

I downloaded the drawing in April last year. Look for a BBS thread about that time.

Stuart
Stuart Duncan

I had the flywheel lightened on my TF. The job was done locally by an experienced outfit in the race car business and they reduced the weight by about 28%, which they felt was perfectly safe, but no further.
Dave H
Dave Hill

Mort,
I need a logical recommendation on WHY you want a lightweight flywheel.
JRN JIM

A lightened flywheel will take less energy to "rev up",, it gives a quicker response. I have heard that it might hinder the road-ability of a road car,, where it won't have the stored energy to give a smooth ride.


Steve
Steve Wincze

Jim,
Steve has answered the question.
I am still evaluating whether to lighten mine or buy a new one. I believe the weight reduction of machining mine would be about half the weight reduction of a new flywheel. That may be the best compromise for my kind of driving.
Mort
Mort 50 TD

Mort - everyone has opinions. I like the lightened stock flywheel, and do it to every engine on which I work. I find about a 25-30% reduction in weight makes the engine rev up noticeably quicker, and the car just feels lighter, more agile. I have no problems off the line, where the biggest inertia has to be overcome.

I am not a big fan of the aluminum flywheels (altho many are), because the ONE time I drove a TD with a lightweight, aluminum flywheel few years ago, I kept stalling unless I feathered the engine and clutch at about 3500rpm. That's a pretty small sample on which to base my opinion; on the other hand, your car has enough power that it may not be an issue. If you're racing, a lightweight flywheel is an obvious choice, but for a street car, a little bit goes a long way.

When in doubt I tend to be conservative, since pulling an engine does take time and effort.

Tom Lange
MGT Repair
t lange

To each his own. The issue the engine revs a few thouandth of a second faster blipping the throttle is not on my priority list.

There's also the argument bald tires will make it faster, too. Let common sense prevail.

A kilogram of flywheel is a drop in the bucket with respect to a thousand kilos of car mass.

Performance minded characters think lighter flywheels improve performance. Engineers know otherwise, they designed them.

I'd rather have that extra flywheel momentum for improved takeoff, smoother idle and less engine vibration. I'd save my money for modifications that provide a benefit.

Save your money, Mort!
JRN JIM

I have a flywheel and Clutch that came in a box of parts with my TF restoration. The ring gear is 10 3/8 inch in diameter and needs to be replaced. I want the pressure plate is Borg & Beck part number 44638. Is there any interest before I list on ebay? Pictures available.

Rick

I have the brown and gammons "window" flywheel in my TF. It has the cortina clutch as supplied by Manley Ford. I did not notice any challenges in getting started or changes in the smoothness of idle. I did notice an improvement in throttle response though. That I appreciate when doing a heel toe change going around a corner where I need to fetch 2nd to go up the hill. I would certainly do it again if it came about.

Alex
Alex Waugh

Jim, with due respect, what engineers claim that reducing rotating mass does not improve overall performance? That's contrary to 100 years of automotive development.

I directly compared a stock weight flywheel to one lightened by 8 pounds on my TC. No other changes to the engine other than a new clutch, just replaced the flywheel and went for a drive. The difference in throttle response was definitely noticeable. My impressions were...

- Improved throttle response at all RPMs
- Much faster revving in neutral, and during off the line acceleration
- Little to no difference on resistance to stalling
- Slightly more "neck snap" when shifting quickly
- No difference in running smoothness of engine
- Very slightly more sensitive to unintentional throttle changes over bumpy roads
- Increased "lurch" when engine braking

So I'd say if you're after performance, then it's worth the $40 to lighten and machine the flywheel. If you're just cruising around town and aren't the type to heel and toe, may as well stay with the stock, heavier weight for maximum ease of shifting, etc.
Steve Simmons

I don't have a lightened flywheel, but I've often thought about having it done for the track. Changing down is no problem - the revs come up very quickly with a heel-and-toe during braking. But waiting for the revs to drop when I'm changing up is a real pain.
David Provan

This thread was discussed between 23/02/2016 and 27/02/2016

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