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SCCA F Prod CRX Si
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70 Posts
Discussion Starter #1
It's halfway through the race season so it's time to plan the winter build. I've decided the west coast tracks need the ability to go down to 2nd gear for tight corners. That or the engine now makes enough power that I can tell when I'm lugging it in 3rd. Either way I'm losing time and distance to the competition coming out of the tight slow corners. (Approx 45mph in 3rd)

The rules allow any synchronized transmission with any gear ratios and final drive with a 2.5% weight penalty. 48lbs for the crx.

The crx's L3 transmission has a fragile die cast 1-2 shift fork, and I'm still improving my shift quality, so I've already had problems. Back in the day I did bend a 1-2 on my autocross '97 civic. Looking over the specs I'd rather bend a steel s40 1-2 than snap an aluminum L3 or p20 1-2 fork.

Here's the build I'm thinking:
-innovative mounts for the hydro trans in the crx including the cable adapter.
-later (1 year?) the cable adapter will be replaced with a full tilton pedal assy and hydro clutch activation when I redo the brake controls.
-s40 EX case (40mm bearings)
-s40 EX 3rd gear in place of 4th
-s40 DX 2nd gear and 4.0 FD
-mfactory 3rd and 5th (yes I've calced gear splits)
-Quaife out of my L3 Si (40mm bearings)
-later I may play with clutch type LSD's
-syncrotech rebuild kit

This should give about 70mph in 2nd with close splits up to a 125mph top end. (7400 rpm limiter)

Thoughts?
 

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Brokedick Millionaire
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40,312 Posts
Will still end up replacing 3-4 sleeves and shifter forks due to wear. The S40 forks wear faster, but they don't break.

Find out who owns this Tipple/Newcomb tranny I built....



or talk to Fred about his CRX tranny.

You will find the 1.782 second will be too close to the MF 1.565 3rd, I prefer about .30-.35 ratio splits on 2-3 and 3-4...Also use a CRX 1.259 third gear, will only need one machine step instead of two.

For example, a future FP build

3.25
1.65 (HF)
1.346
1.066
.878
 

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Del Sol EH6
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173 Posts
Yea, the 2nd gear will be to close to the MFactory 3rd, like transzex already said. I think the 1.9 2nd is already to close.
 

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SCCA F Prod CRX Si
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70 Posts
Discussion Starter #4
Thanks for the input. I'll look at the splits again. The DX 2nd looked like an easy one to source and I am just looking to fill a hole in the odd once per lap dead spot.

I have plenty of crx 3rds. Is there info out there (specs?) on the machining that needs done or do I need to wait till I get both gears to figure it out?
 

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See above...
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13,322 Posts
Bone, do you still recommend the cast forks over the steel due to breaking one vs bending one does overall less damage to the other components? Might be worth it if spending thousands on your internal trans components.
 

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Brokedick Millionaire
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40,312 Posts
A toss up to me, but the cast forks are no longer available, Aquafina might know better on the 96-00 parts supply.

Reminds me, I need to find a few old 3-4 forks to send out to see if viable to make them.

I'd rather be at WMHM to meet him though...
 

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2,003 Posts
D2B?

Also as a side note to NOT get that innovative cable to hydro adapter, that whole idea is garbage. Even bleeding the shit out of it and adjusting it with a new cable it was still garbage and BARELY driveable with a street car trying to shift slow and smooth. For a race car 100% no.

I have a DIY up for how I mounted a 92+ civic CMC on my CRX, it works WAY better than that garbage.
 

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SCCA F Prod CRX Si
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70 Posts
Discussion Starter #9
I've looked a little for the machining. I'll spend some more time on it.

Thanks for the info on the cable adapter. I put that up to see if there were complaints. May just have to do the tilton assy. Or the hush one season then sell it when I do the tilton.

I thought about D2B and then I could drop $7k on a sweet dog gear set. But that's all over kill right now.
 

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1996 Civic Type DX
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4,167 Posts
If you use the 1.781 2nd, the shortest 3rd you'll want is the 1.346. 1.565 is too small of an RPM drop to give any decent speed gain before shifting to 4th. If you're bending steel forks, you're doing something very wrong.
 

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\/Your Mom Was Here\/
Vibe GT
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4,833 Posts

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\/Your Mom Was Here\/
Vibe GT
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4,833 Posts
Try this?
bensebuilt

Bense is love, Bense is life.

PS: Fuck photobucket. Shittiest image hosting service ever.
Yeah, I host all my images here. Only this place can cause them to be lost, I won't ever delete them.
 

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1996 Civic Type DX
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4,167 Posts
Bense didn't know about machining the OEM 3rd when using it as 4th. He also isn't experienced with real world gearing setups and actually did a lot of stuff wrong when assembling transmissions.
 

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Classic Man
Civic
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16,355 Posts

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1996 Civic Type DX
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4,167 Posts
Sorry you feel the telling the truth is talking down. I'm not going to keep my mouth shut so I can appear like a nice guy. I've shared more trans technical info on here than anyone else. Most of the stuff you regurgitate (incorrectly most of the time) is stuff I originally posted.

I have several trans parts sitting here that were purchased from Bense, that are unusable because of stuff he did wrong and didn't feel the need to disclose before selling. He also only ever ran three different gearing setups and none of them on a road course, which is what this thread is about. I've run every gearing combo possible (except for a few, which would cause the engine to over rev on upshifts), and all of them were run on road courses.

The Y8 trans isn't stronger than the Z6 aside from the shift forks.

My name is Chris, write that down.
 

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Brokedick Millionaire
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40,312 Posts
That being said the Y8 trans is better mathematically and strength wise. They tried to make it more B series-esque.
.009 is not enough to even be noticeable, 1.900 Z6 vs 1.909 Y8 2nds.

Other weak point on 96-00 shift forks, only forks I've had this happen....and more than once.



 
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