I finally installed my CX tranny in the HX and got over 50mpg! This is the first modification I have made that has made a drastic impact on FE and I am tickled pink!

Good stuff!

I assume you swaped out a 5 speed for another 5 speed? can you give us any info on the change in engine speed, problems incountered while doing the swap, and how much of your improvement was due to driving style and how much of it was due to the new transmision?
Do you have a scangauge? it's new enough.

These ratios aren't entirely accurate. You got these from the knology site which has a few errors.


Yes.



I'm not sure if you guys realize this. But HX's have been known to have the b000 on the stamp near the fill plug. A few 3.25 final drives from the cx/vx have been found in the hx trans. HX trans have a 3.7222 final drive with a 0.702 5th gear.

Most HF trans have the final drive of 3.25, not 2.95 like the knology site lists. I believe its only the 1988 HF that came with the 2.95 final drive. The only problem is that the spline count on the input shaft for the 1988 trans is different, so you'd have to swap clutches and pressure plates. So the only real feasable HF transmission is the 3.25 version. So the only difference in your cruising gear is the 5th gear of 0.694 instead of 0.702. We're talking 1.1% difference in gearing. Not enough for any of you guys to notice. We're talking 30rpm less per minute if that.

My HX had the 3.72 gearing. At 65mph it cruised at 2500rpm. Driving technique was keep at or below 65mph, shift at 1500rpm between gears.

Now, with the 3.25 CX tranny I drive 65mph at 2100rpm. The gears are alot longer so I can easily hit the 1500rpm shift point in 1st. It is slower and I do lug the engine alittle now taking off because of the longer gears.

I have consistently got 43-45mpg with the HX while trying my hardest to get my previous goal of 50mpg. Now I drive the same way and I am able to pul out alittle over 50mpg. It is the gears and I suggest this swap to any gassaver without a doubt.

One thing to mention is that the faster I go the more I notice the longer gearing. The first thing I did with the car once it was on the road was take it on the highway. I went 80mph and was at 2700rpm rather than 3700rpm. That final drive gear is LONG. Honestly it was easier to cruise at 65mph with the HX transmission because the rpms were higher. Now I can go 70 and still have lower rpms than 65 with the HX. I just have to watch the speedometer more now....

Oh yeah, no problems with the 5-speed to 5-speed swap. I bought new driveaxle seals from Honda for about $10 each. I also installed a new ebay clutch kit. It cost $85 shipped and was an exedy oem style. This clutch is softer than my other clutch and took alittle getting used to. The hardest part of the job was aligning the transmission with the clutch on the engine. I ended up rotating the engine very slowly while my dad shook the transmission back and forth. Total install time was 4 hours including travel time for tools from the house to our shop.

My buddy with a 2000 Si wants me to install the HX tranny in his car for better FE. When installing a d-series onto a b-series I am guessing I need d-series driveaxles, HX tranny, and d-series flywheel and clutch (or just clutch?). Is this correct? Is it better to use the HX flywheel/clutch or the Si flwheel with d-series clutch.

I heard they bolt up fine and any info is appreciated. His rpms are WAY high with the Si tranny....4.400 final drive.

My CX tranny also had J8B on the serial stickers.

What size tires are you running? I'm running about 2500 at 65 with my CX tranny with 175/70/13's.

I mis-spoke earlier. I'm running 2250 rpm at 65 with 175/70/13 tires. I apologize for the bad info, need to avoid doing things quickly when I'm tired. :0

-- Scott

who's the guys with the vx trannys i need one rater quickly drop me an email begoodchopshop@chicagoz.com