ok i have a 1990 crx and im gonna put a d15b vtec with my DX tranny and go turbo.
my question is would my DX tranny hold me back or would it be ok?
big difference with the SI tranny?

 

never driving a car with an si tranny. but it would be faster but slower top end. dx tranny would get better gas milage too.

 

makes a pretty large difference, after driving one i don't see how honda could have ever offered another tranny with a d series. you'll get around fine with the Dx but it will definately not be at its full potential with the Dx final drive ratio.

 

I wouldn't say that it's a big difference, but it is definitely noticable between the two. I swapped mine dx out for an si. I still have it in storage, only if the si one breaks, or while I am installing an lsd in the si.

 

If you plan to go turbo,I'd personally keep the DX tranny.The Si is geared tighter but is buzzy in 5th gear.Stay away from the HF tranny though,its useless for the track but would be bad *** for top speed runs.Also finding as Si tranny thats useable is almost impossible,at least around here.Most the ones that I was going to buy had a cracked case

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by subgeniusdude &raquo;</TD></TR><TR><TD CLASS="quote">If you plan to go turbo,I'd personally keep the DX tranny.The Si is geared tighter but is buzzy in 5th gear.Stay away from the HF tranny though,its useless for the track but would be bad *** for top speed runs.Also finding as Si tranny thats useable is almost impossible,at least around here.Most the ones that I was going to buy had a cracked case</TD></TR></TABLE> Why would you take the DX transmission? Is it because you "think" it'll be faster?

http://forums.evans-tuning.com...=1496

 

the si and dx arent geared differently, they just have a different final drive.

si is not geared "tighter"

 

i always thought the si trannys gears were "tighter" aswell. but im not an expert on it at all.. if so then why do people like si trannys so much? id rather have my rpms low in 5th for cruzing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by janz3n &raquo;</TD></TR><TR><TD CLASS="quote">never driving a car with an si tranny. but it would be faster but slower top end. dx tranny would get better gas milage too.</TD></TR></TABLE>

gas mileage is mostly dependent on throttle position. not gear ratio.
i would get the si tranny. u wont stay in boost as long, but the turbo will spool faster and acceleration will be quicker. SI

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by janz3n &raquo;</TD></TR><TR><TD CLASS="quote">i always thought the si trannys gears were "tighter" aswell. but im not an expert on it at all.. if so then why do people like si trannys so much? </TD></TR></TABLE>

because

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by redzcstandardhatch &raquo;</TD></TR><TR><TD CLASS="quote">the si and dx arent geared differently, they just have a different final drive.
</TD></TR></TABLE>

 

With owning a 89 ef and having the a6 with the Si tranny I will say that it is geared in a way that isn't that great for highways, but at the same time I can get over 600km to a tank of gas in my car.

How heavy your foot is in a ef with the si tranny I find really plays a part in gas mileage. I can get anywhere between 400-500km on a tank of gas depending on how hard I drive it.

 

well...if you're so intent on having an Si's gearing, even though it may be the same as the dx, minus final drive, you can find an Si with a cracked case or whatever, and put the gears into the dx.

 

anyone know where i can buy one?or selling one? im in SO CAL.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by redzcstandardhatch &raquo;</TD></TR><TR><TD CLASS="quote">the si and dx arent geared differently, they just have a different final drive.

si is not geared "tighter"</TD></TR></TABLE>

please stop giving out false information...

the trannys are geared differntly, the dx has a 3rd gear of 1.172
and the Si/EX has a 3rd gear of 1.250, both final drives are also different with the SI/EX having 4.250 and the DX having 4.058
and 5th gear in the SI (hatchback only) has a ratio of .750 whereas the EX (coupe) has a 5th gear of .702

the best combination *of the two trannys being discussed would be
1st: 3.250 (from either tranny)
2nd: 1.900 (from either tranny)
3rd: 1.250 (from the si/ex tranny)
4th: 0.909 (from either tranny)
5th: 0.702 (from the DX/EX tranny) NOT SI
FD: 4.058 (from the DX tranny) will yeild a higher top end, and be better for cruising (80mph in 5th gear would be at about 3300RPM)

 

well all im saying is i have a dx tranny, and going 140KM/h im at about 4 grand ... seems high to me. wish i had another gear so i could be at about 2000 or 2500 .

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EGRhatch &raquo;</TD></TR><TR><TD CLASS="quote"> please stop giving out false information...

the trannys are geared differntly, the dx has a 3rd gear of 1.172
and the Si/EX has a 3rd gear of 1.250, both final drives are also different with the SI/EX having 4.250 and the DX having 4.058
and 5th gear in the SI (hatchback only) has a ratio of .750 whereas the EX (coupe) has a 5th gear of .702

the best combination *of the two trannys being discussed would be
1st: 3.250 (from either tranny)
2nd: 1.900 (from either tranny)
3rd: 1.250 (from the si/ex tranny)
4th: 0.909 (from either tranny)
5th: 0.702 (from the DX/EX tranny) NOT SI
FD: 4.058 (from the DX tranny) will yeild a higher top end, and be better for cruising (80mph in 5th gear would be at about 3300RPM)</TD></TR></TABLE>

Ok, where did you get these numbers? From numerous reference sources and transmission builders the only differences (outside of the HF and STD 4-Speed) between the transmissions are the Final Drives.
3.88 for the DX/LX
4.0xx for the EX Sedan (never had an EX coupe)
4.25 for Si

With gearing being the same on all five ratios.

 

[Quote: please stop giving out false information...

the trannys are geared differntly, the dx has a 3rd gear of 1.172
and the Si/EX has a 3rd gear of 1.250, both final drives are also different with the SI/EX having 4.250 and the DX having 4.058
and 5th gear in the SI (hatchback only) has a ratio of .750 whereas the EX (coupe) has a 5th gear of .702

the best combination *of the two trannys being discussed would be
1st: 3.250 (from either tranny)
2nd: 1.900 (from either tranny)
3rd: 1.250 (from the si/ex tranny)
4th: 0.909 (from either tranny)
5th: 0.702 (from the DX/EX tranny) NOT SI
FD: 4.058 (from the DX tranny) will yeild a higher top end, and be better for cruising (80mph in 5th gear would be at about 3300RPM) Quote.]

your be our D-series gear calculator night in shinning armor if we were talking about EG chassis d-series gear ratios but we are not, we're talking about EFs and in the EF chassis Dx and Si trannies have the same exact 1-5 gears, the only thing separating the two is the final drive ratio and the fact that the SI has bigger bearings. those numbers you gave are for EG trannies. Trust me i know, i have a Dx/Si hybrid in my car now and all i did was took the complete countershaft from an SI and took the ring gear from an Si and put it all in a DX tranny, the gears are identical, i had them apart side by side. if they were'nt the same the my Si countershaft would'nt mesh too well with a Dx mainshaft that had different gear ratios now would it.

 

reading pwnz mE!!! lol

sorry!

 

i dont think ex and si final drives are the same, ex has 4.025

 

haha..i'm right.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EGRhatch &raquo;</TD></TR><TR><TD CLASS="quote">

please stop giving out false information...

the trannys are geared differntly, the dx has a 3rd gear of 1.172
and the Si/EX has a 3rd gear of 1.250, both final drives are also different with the SI/EX having 4.250 and the DX having 4.058
and 5th gear in the SI (hatchback only) has a ratio of .750 whereas the EX (coupe) has a 5th gear of .702

the best combination *of the two trannys being discussed would be
1st: 3.250 (from either tranny)
2nd: 1.900 (from either tranny)
3rd: 1.250 (from the si/ex tranny)
4th: 0.909 (from either tranny)
5th: 0.702 (from the DX/EX tranny) NOT SI
FD: 4.058 (from the DX tranny) will yeild a higher top end, and be better for cruising (80mph in 5th gear would be at about 3300RPM)
</TD></TR></TABLE>When did they make an 88-91 ex coupe?

 

he thought we meant 92-95