I have a quite strong Z6 in my 88si. it ran a 15.4 in my 2700lb 92 sedan, and since it was put in the crx i added a hedder, and a zex ultra light flywheel. my only choice at the time of the swap was a 89 civic dx tranny. this thing is much slower than i expected, feels about like the 4dr. i could hear VTEC change over in the sedan, but not in the crx, i'm thinking because the gears are stretching engaugement out so long. i checked the solonoid(sp) and put a meter on the wire, so VTEC is there..

my question is, is the DX tranny really that much slower???

 

the difference between the dx and si is the final drive gear. The si has a 4.25 ratio while the dx is like a 3.88. other than that the gear ratios from 1st to 5th are the same

 

i understand that, but the FD makes all the difference in the world, it's the last gear it sees before the wheels...i just wanna know if it is really that much slower on launch

 

with my DX tranny, i ran a 15.7 here in tucson, thats like a high 14, low 15 in socal, havent been to the track with the SI tranny yet, but ill let you know after jan 31. lets just say that with the SI tranny, i now beat cars by 5 car lengths that used to beat me by about 2 car lengths. its totally worth it IMO.

 

Yes the DX trans is much slower than the SI. An old roommate of mine had a 91 hatch, ZCmotor/DX trans. I had my car which is an 89 hatch w/ ZC motor and trans. I would walk him like he was still driving the SOHC DX motor. So yes, it is a poor tranny. Great for gas mileage.

 

k i can help.. been there done that

i had my STD 4 speed tranny and i ran a 16.9 as my best run with my Z6
swaped a Si tranny and ran the 15.9 that it did
now i broke the Si tranny and swaped a DX...
i CAN feel a difference i acceleration... but u can mainly feel it on 4th and 5th
1st its basically the same... 2nd and 3rd are lil more longer (about 4-5 mph)
ill say that the difference can be felt on how light the car feels... with the Si tranny it feels its lighter ans smoother... the DX its a lil more tq feeling since its making a lil more power... i gotta say that despite the fact it has a diff FD i kinda like doing 75 mph @ 3200 rpms.... i am really considering keeping the DX and just making sure my car can go fast with that tranny and get a lil better gas mileage.. specially if u do a lot of highway driving... and even with that i can push my car up to 110 in 4th with no probs....

 

I've run DX, Si, and ZC transmissions on my ZC engine. DX sucks. only use it if you have to get your car on the road like yesterday. Because of the Final the gear spreads are way wrong for the ZC. THe ZC hits redline in 2nd gear at about 85 mph, Its a real slug with this box. Doesn't feel any stronger than a stock '89 DX engine because it won't rev with these gears. Si is a LOT nicer but bad torque steer, ZC box just as nice as the Si, but no torque steer due to its use of and intermediate shaft. I have the ZC box now and am quite happy with it. Have a perfectly good DX box sitting in my garage. 108,000 miles no grinding and no noise. Shame thay are next to worthless. And By the way with a ZC there is a HUGE difference on how fast the car is. Being as I have driven the same car with the same engine with all three types of transmissions. And I noticed no difference in gas milage since you had to give it more juice to keep up with traffic with the DX and with the Si or ZC it cruises contently with no effort at any speed I have ever driven it on the highway (up to 90mph) Couldn't say that with the DX box that felt like the car was towing a large boat all the time.


[Modified by virginia_dude, 3:03 PM 1/13/2003]


[Modified by virginia_dude, 3:05 PM 1/13/2003]


[Modified by virginia_dude, 3:08 PM 1/13/2003]

 

I've run DX, Si, and ZC transmissions on my ZC engine. DX sucks. only use it if you have to get your car on the road like yesterday. Because of the Final the gear spreads are way wrong for the ZC. Si is nice but bad torque steer, ZC box just as nice as the Si, but no torque steer due to its use of and intermediate shaft. I have the ZC box now and am quite happy with it. Have a perfectly good DX box sitting in my garage. 108,000 miles no grinding and no noise. Shame thay are next to worthless.

 

Next to worthless, then you wouldn't mind giving it to me then would you???

 

My HB is a DX and I absolutely hated the stock tranny. My Si/ZC tranny is SO much better.