just to pile in here:

i will be using a WR toploader with a 2.88 diff when my FE428 arrives. i wont have the fastest accelerating car, but at least it wont be on very high revs at 70mph. i want 4 speeds that will be useful, and i'll sacrifice a little acceleration on the way.

I know several UK FE guys who are swapping to taller diffs having used 3.38 with tremecs.

KevinW, I don't know about that, It wouldn't surprise me if it was FASTER than if you had lower gears!

I was running some pretty tall gears myself, with a C.R. first gear was good for about 65 mph! Sure, I was "slow" out of the hole but STILL had to deal with tire spin. It would "hook up" just beyond the 60 ft mark and THEN I could put the hammer down 100%. Just about everyone I ever ran against got the "hole shot" on me, that would give them "hope",,, just before I blew their doors off and crushed 'em like a bug. :)

Don't underestimate tall gears in a light weight Cobra with limited traction, it may well be just the ticket!

Whether you get those tall gears with a higher read end ratio (lower numerically) or a taller 1st gear trans ratio, the end result is the same, more control of the traction problem.

I hope you don't mind me butting in, Duane, but here is my opinion on the aluminum/steel flywheel issue:

I think for the street an aluminum flywheel is kind of excessive (pretty much just like the car itself!) and I highly doubt that most of us coud tell the difference in how quickly the car accelerates with an aluminum flywheel as compared to a steel one....a light flywheel (some of the steel ones are pretty light too) just makes the car a little harder to get off the line as it doesn't have that "flywheel effect". (hmmmm)

However, the reason why I used one and continue to use one is pretty lame....I just love how quickly the engine revs when you rev it when stopped and how quickly the engine stops when you shut it off. Real racy sounding.

A friend has a stock steel flywheel in his ERA and that things sounds like an old Lincoln when he revs it. :( Sure drives nice though. :)

ZOERA-SC7XX: You are correct. Will be 3200 rpm's or so. Just fine to me.

Merry Christmas
Byron

Thats a good point Pat, I know exactly what your talking about, not "lame" in my book, part of the "feel" that enhances the whole experience.

C.R. is also a factor. There is noticable difference between my old motor, 12.5 to 1 C.R. and my new motor at 9.6 to 1. Both with the same flywheel in my case (heavy Hays).

Pat, Ex,

Sorry, I couldn't help myself to ask the question, and not to totally hijack the thread, but I'm always fascinated about the the different reasons people use this or that part and what they determine the pros/cons are. Since I don't track my car much or do heel/toe shifting these days, I guess I'm probably okay as-is. ;)

On my last Cobra with FE, I had the heavier stock 55lb or so flywheel and it did idle smooth, snap-revved slower, and (yes) ran like a passenger car at idle, but holy smokes when that thing picked up and got rolling off the line with 3.08 rear axle ratio it came on like a freight train, and kept pulling like a freight train. The car had a bit less hp than my existing motor, but the former setup was like a slingshot out of the hole without blowing the tires off so easy. It actually felt faster on longer straight runs than my existing car which has more hp and a lighter flywheel today. However, if you got the tires to break loose with the heavier flywheel setup, watch out, it would keep the rpms up and just burn the tires all the way down the street, and keep going if I kept my foot in it. It was actually kind of ridiculous now that I think back on it.

With the midway 32lb steel flywheel I use today on the 2nd car, it does rev faster, and does idle a tad more radical, and with 3.31 it feels good all around but does not seem to have that same type slingshot feel out of the hole. In some instances I actually liked the behavior of the heavier flywheel and close ratio 4 speed for longer straight runs when banging through the gears; but only for that type of use. Otherwise, I still prefer 3.31 axle ratio with WR trans all around with a mid-weight flywheel.

How much does a FE manual flywheel weigh? If you wanted to go to a lighter flywheel for the street and track what would be a good weight ?
Jon

The stock flywheels are about 50-60 lbs (I think), aluminum ones are about 14-20 lbs.

You're pretty much limited by what are sold by Fidenza, McLoed, etc....

I would do for the heaviest of the lighter flywheels - around 20 lbs.

Here's a link.

http://www.summitracing.com/search/M...minum+flywheel

Here's some weights for the stuff I sell:

Fidanza aluminum - 14 lbs
PRW/CAT billet steel - 35 lbs
McLeod billet steel - 28-35 lbs
McLeod aluminum - 18 lbs

For an all-around street car, I like a steel flywheel. If you're going to track the car at all, I'd go with a Fidanza aluminum flywheel. They are excellent quality, light, inexpensive (for an aluminum wheel) and made in the US (Ohio).

I can't recall exactly but it seems to me my HAYS steel wheel was about 40 pounds?

I like the steel wheel myself, mostly street driving.

For street, I like a close ratio toploader with a wide ratio first gear for launching. 3.70 detroit locker rearend & 26" tires.

How do we accomplish that setup? Seems I'd like a little lower 1st gear.

Hi Guys,
The flywheel is only a partial weight of the reciprocating weight. With an FE crankshaft that weighs in about 65 lbs and the pressure plate is bolted to the flywheel too. Many factors on whether an aluminum or steel flywheel must be considered before a purchase is made. Most go back to overall 1st gear and camshaft profile.
Note: Crankshaft reciprocating weight is worth 3 times dead weight.... So a flywheel 15 lbs lighter is worth 45 lbs of dead weight.

Happy holidays Jon
 

saltshaker Jon your question is not that cut and dry. The main problem is that we don't know the torque band of your motor. HP comes in around 3,800 to 5,500 rpms. You are not going to spin this thing at that high rpm all the time, SO here's what I can tell you from my setup. I started with a #40 steel flywheel, 3.31 gears and a 3.25 first gear with an overdrive. 1st is good for parades only at 1/2 mph per hour. Never used it to race, the shift is within the first 20'. Race trans has a 3.05 first gear and the same problem with quick shift and spinning the tires. Went to a 22 pound flywheel and got 2 things, the motor lugged a little off the line and stop smoking the tires but once moving the accelleration was quicker by about .2 seconds. Have to remember that my motor is all torque and the hp band is all done by 5,600 rpms. The thing is this you want the car cruising about 500 rpms above the base torque band to start.
Jon if you are looking to swap or buy another trans, get a overdrive 5 speed, either a richmond super street or TKO-600 with a 2.87 first gear. overall this will give you the best of both worlds. If you are going to spend alot of time idling around town, heavy flywheel in the 30-40 pound range. If you are looking for highway cruising, 22 pound flywheel will work out IF the camshaft is not to big, does not have a ton of overlap and a 112 LSA. If a nasty camshaft is in the motor you are back to the 30-40 pound one. It's a trade off.
2 side notes, if you buy a new flywheel, make sure it's SFI certified and it has a zero balance rating. The other thing is that WR tran's are more for starting heavy loads off from a stop. First gear is alot of the time in the 3.00 ratio or high 2.80's. CR tran's was designed more for 1/4 mile racing and keeping the motor in a narrow rpm range( powerband). It was between max torque and 500 rpms pass max hp rating. The weight of the car also is taken into account. IMO find a trans with a 2.60 first gear stay with the heavy flywheel and the car will run fine. Go to a 2.80 if you are looking to run a littler flywheel. Good luck Rick L.

WR/3.31...good combo for street and open track.

I bought a close ratio Big In/Big out Toploader then had a tranny guy swap 1st gear out for the wide ratio first gear.