MGB MGB Aluminum Flywheel

[testaj]

I am contemplating putting an Aluminum flywheel into my stock 66 roadster. I have done a search and while there were a few threads on the topic, there was nothing that definitively mentioned whether this will work well or create drivability issues. Has anyone tried this on their stock street B with any success?

 

[tony barnhill]

Don't know why you would want to do only that modification....only thing it'll do by itself is lose you a few pounds.

 

[testaj]

Don't know why you would want to do only that modification....only thing it'll do by itself is lose you a few pounds.

Thats what I figured, however the people selling it claim a 15hp increase which I find hard to believe. I am guessing it just helps the engine rev faster.

 

[tony barnhill]

There could be some small increase but you'll also find that with no other modifications, its hard to get the car on & off a trailer or even pull off from the start due to the lightness ofv the flywheel.....I'd add one along with other modifications.....you can get the 15hp easier & cheaper doing other things.

 

[Steve_S]

Lightening the flywheel will do nothing to increase horsepower. It will only reduce the rotating mass, allowing the engine to rev more quickly. This gives the impression of more power because less of the engine's torque is used to get the flywheel moving. A lightened flywheel will also make the car easier to stall when starting up in traffic.

 

[Hap Waldrop]

Lightening the flywheel will do nothing to increase horsepower. It will only reduce the rotating mass, allowing the engine to rev more quickly. This gives the impression of more power because less of the engine's torque is used to get the flywheel moving. A lightened flywheel will also make the car easier to stall when starting up in traffic.

Steve you make me proud , Steve nailed it. An aluminum flywheel is a pretty good weight drop, like 10+ pounds so it's a eye awaking mod, I like the feel of the aluminum flywheel just fine in the MGB, makes it rev the way it should have from the factory. I have a new Fidanza aluminum flywheel put up for my own personal 1900cc MGB engine build. I will warn you, the three syncro flywheel in aluminum is a hard find, most of your normal vendor will only have the later 4 snycro units in aluminum, give me a call, I'm a Fiadanza direct dealer, maybe I can find you one, they have to be ordere in lots of 7+ units by a dealer, not a high demad unit, so sometimes the part number runs dry or NA for lengths of time.

 

[BizJetGuy]

What kind of price range would one be looking at for a 3 synchro Al flywheel, Hap?

 

[SpitFyre]

More information than you could ever want. https://www.pumaracing.co.uk/FLYWHEEL.htm

 

[Hap Waldrop]

What kind of price range would one be looking at for a 3 synchro Al flywheel, Hap?

First one would have to find one, give me a call if you want me to look for one, fiquire $450ish depending on who has one, (the 4 snycro can be had for alot less, priocngi is based on the qquanities in which a part number is producued) if anyone has one. I know people who have such things horded well outside the normal paths, it just if they have one of those.

 

[Hap Waldrop]

More information than you could ever want. https://www.pumaracing.co.uk/FLYWHEEL.htm

I've done my fair share of lightening stock flywheel on my lathe as well, horrible job to do, one of my least favorite things to do, so I rarely do them, normally only as part of complete engine build. It one of those jobs you don't really care if you make that money or not

 

[testaj]

What kind of price range would one be looking at for a 3 synchro Al flywheel, Hap?

One on ebay right now for $340

https://cgi.ebay.com/FIDANZA-ALUMINUM-FLY...id=p3286.c0.m14

 

[Hap Waldrop]

What kind of price range would one be looking at for a 3 synchro Al flywheel, Hap?

One on ebay right now for $340

https://cgi.ebay.com/FIDANZA-ALUMINUM-FLY...id=p3286.c0.m14

Thats Ultrarev,he's maybe their biggest buyer, mostly Jap stuff, but sometimes he has one of our units in stock, thats a killer price, he's blowing it out I'm sure to move it off the shelves. I would grab if I wanted one. The deal is when stock on a given part number it exhausted, a minimum order of 7 flywheels has to be made, so if you're a retailer, you have to look hard at that part number and how it sold, and how will it sell again, this is pretty dead part number, so it can and will dry up totally at times, and can stay that way, for years at a time, for example no one carries 948 Spridget aluminum flywheels no more, and no one would want to have 7 made at one time. The information on the Ebay add is wrong as far as it fitting 3 main MGBs and MGAs, that is incorrect, they register against the crank totlally different than the 5 main stuff, but that is the correct part number for a MGB 5 main 3 syncro gearbox, I know, I have a new one sitting here to look at.

 

[vping]

10 available and right here in Brooklyn. hmmmm....

 

[Hap Waldrop]

10 available and right here in Brooklyn. hmmmm....

Yeah maybe, you have to know those cats at Ultrarev, weird bunch to say the least, but their prices are good. Basicly aluminum flywheels is market not many of us compete in anymore, because it's been prostituded out They give me a nice discount if they have what I want, but seldomly have what I want. I've only sold two aluminum flywheels for 3 syncro MGB 10 years,(I sold plenty of the multi racing disc units), and fiquire I've probably sold 150 Fidanza flywheels so far. It's e real dead part number for the street, most street MG guys are scared to use aluminum flywheels.

 

[vping]

Why scared?

 

[PAUL161]

Hap, years ago when we were running circle track modifieds, we used aluminum flywheels to get more snap out of the engines. Only problem we found was the engines wouldn't idle as well and would lope more. Naturally it was no problem on the track, but I would think it might be annoying on a street machine.
Also we had to replace those flywheels fairly often as they would gall out, go out of balance and cause a high frequency vibration. I remember one flywheel had a brass face in-bedded in it. I'm sure the metal composition in the flywheels are much better today than back then.

 

[DrEntropy]

With a street driven car I'd stay away from an alloy flywheel simply for the inconvenience factor. Driving in stop-and-go traffic will become a chore and will decidedly add to early demise of the clutch/flywheel. Racing is a whole diff'rent animal. :wink:

Hap doesn't like the process of lightening a steel one (I understand why) but if it were me that's the path I'd take. I can't recall which but Vizard, Trickey or the Competition Manual (Special Tuning) has a good illustration about how/where to cut meat off the stock one.