anyone running these? whats your input on it and has anyone broke one?

thanks guys.

 

The longer the first gear the higher the wheel speed at launch. The high the wheel speed the more it blows the tires off and claws less.

 

I have a 3.0 first gear and it works good for me. Our track doesn't hook the best so low power and a longer first gear helps get the car off the line. Also the rpm from first to second stays up so you can keep the power out if the track is not hooking all that good.

 

Ran multiple ones, broke multiple ones, only thereafter did MFactory say "don't run it with a 26" slick"

Went back to the 3.23 ratio and 4.4 FD and the problem was solved

 

lol. ok.

anyone else?

 

I'm curious about a longer first gear as well. Seems like the reduction in torque would help with traction and keeping te RPMs up for the 1-2 would be beneficial as well.

In for more input!

 

Many people have ran them with great results. ATS use to also make a similar 1st gear. All work well

 

i plan on putting one in my tranny that i will be building for the streets to use with some 26's

 

I used to run a similar 1st gear (from KAAZ) about 15yrs ago, great 60' times and even great on burnouts...the clutch took the brunt of the stress as well, at that time there were no twin disc clutches, i used a cintered iron single and still got high 1.4 60's and no tranny breakage...

 

this is a 2.45 first gear with a 24.5 tire reving to 9k its about 60mph in first the rest of the gears keeps the rpm up above 7300 rpms

 

We had one and the synchro ring didn't contact he cone on the gear evenly. I can't remember which half (top or bottom) but it wasn't using all of the surface area available. At least it was first gear and the synchro doesn't get a lot of use.

 

Anyone know if the MFactory 1st gear requires mainshaft replacement? Their website doesn't mention it.

 

no, just the gear.

 

This.

 

I've only ever installed one MFactory 3.07 1st and it's on a lower hp all motor car. And it is JUST the countershaft gear to the poster who asked; not the mainshaft as well.

I've actually been concerned with this regarding aftermarket gear companies and the gear cones (not just 1st gears). Good to see I'm not the only one bothered by this.

 

What kind of differences in the short track did you see?

-Eric

 

Well, the setup (H2B-swapped CRX) never ran without it to compare and it was the driver/owner's first time at the track. So I don't actually have any solid data for it to be making any recommendation, positive or negative, on the part. :p Only thing I can say is it didn't seem to make it worse than I'd expect with the original 1st and it didn't break yet. LOL

 

I must be having a brain sneeze here but can someone help me understand how you change the gear ratio without replacing both gears? The tooth count would have to be different obviously to obtain a different ratio. How can you change the tooth count on one gear and not the other and not run into gear mesh problems?

 

The 3rd and 4th gears from the same set didn't have the same problem, only 1st gear.

 

I've installed many and driven a few of them. No problems on 24.5" setups. It does cut down on the 60' slightly. Makes for a nicer 1-2 shift. Same with the D series 3.083 1st.

You can change the gear ratio by about .15 with only one gear before it will shred teeth off. Anything more/less than that and it will require a whole new gear set.

 

If the module of the gear tooth is similar enough and the helix at the same angle, you'd be able to alter just one gear. I'm presuming that's what MFactory has done. I personally don't like pairing a new gear to an old gear though. But it's 1st. LOL

 

New gear with an old gear is perfectly fine to do. I've not seen any odd wear on 1-5 even after 75,000 miles. No problems on mid-power setups either (500'ish whp). The only time I can see it being a problem is when the used gear has excessive wear, in which case the entire gear set should be replaced anyways.

For future use when people find this thread with a search, do not buy a used 3.07 (3.083 for D series) 1st gear unless you have a brand new mainshaft to use with it. It has already developed a wear pattern with the mainshaft it was first used with and will wear rapidly and be prone to breaking if used with a different used mainshaft.

 

Work perfect! we use for almost 2 years no problem!

we make 1.51 on the 60

 

Any back to back testing results that people can give comparative short track times?

 

On my setup, it would take my first gear MPH from 39.65 to 41.79. Not sure if 2.14 MPH in first is worth the $275. Just not sure I'll see a difference.