TRANNY swap question

[ICEMAN707]

Just wondering...does the carb A20A1 5spd have a closer gear ratio? if so, and if we could swap in a 2nd gen Lude tranny into our cars and we know it has a closer gear ratio, does that mean the 2nd gen Lude's carb engine tranny gear ratio is even closer than the EFi versions too? Let me know cus I wanna swap a Lude tranny into my car sometime soon and the closer the gear ratio, the better for torque and acceleration.

[phrenology]

Just wondering...does the carb A20A1 5spd have a closer gear ratio? if so, and if we could swap in a 2nd gen Lude tranny into our cars and we know it has a closer gear ratio, does that mean the 2nd gen Lude's carb engine tranny gear ratio is even closer than the EFi versions too? Let me know cus I wanna swap a Lude tranny into my car sometime soon and the closer the gear ratio, the better for torque and acceleration.

From the research that my engineer and I have done the closest stock gear ratio in the 3G family is the E2Q5 from the 88 Lxi. I bought one specifically for the low gearing. I'm building a torque beast, I don't really care about going 120mph+. If you want we have the comparison data on a spreadsheet somewhere. It has all of the 3G trannies stats on it. From what I recall most of the 2nd genration preludes use a higher geared tranny for fast top end speed. You'll only be able to use the tranny from the Ludes with the A20/BT/BS engines. They switched when they went with the dreaded B20A5. I think Mr. eff is the one working on a Lude-Accord 5 speed hybrid tranny, ask him.

[mouchyn]

Just wondering...does the carb A20A1 5spd have a closer gear ratio? if so, and if we could swap in a 2nd gen Lude tranny into our cars and we know it has a closer gear ratio, does that mean the 2nd gen Lude's carb engine tranny gear ratio is even closer than the EFi versions too? Let me know cus I wanna swap a Lude tranny into my car sometime soon and the closer the gear ratio, the better for torque and acceleration.

if this car spends any time on the hiway, keep in mind closer gearing will yield high engine speeds on the hiway. in my 3g prelude, my engine turns at just a hair over 4k rpm at 70 mph. it's prety obnoxious if you're on the road for more than 20 minutes or so.

if you want to go faster, add power to the engine. Find a transmission that's comfortable for the type of driving you do, then make the engine create the power/torque -- not the other way around. If you're building a track car, then go for the super short gearbox. If this is your daily driver, i would reconsider finding the shortest gear ratio plan.

[ICEMAN707]

so what tranny do you recommend chris?

[mouchyn]

since my 88 LXi sedan is my daily driver, I'm pretty happy with its stock transmission. I have a 15lb flywheel and a brand new exedy stage 1 clutch. I did some mild porting to the head and intake manifold, bored out the TB, and slapped on a facesitter header and i can rip through my gears pretty darn fast. I can lay rubber all the way through 1st gear, most of the way through second gear, and chirp 3rd gear if i power shift.

0-60 betwee 6.5 and 8 seconds depending on my tires and the weather.

on the hiway at 80 mph, the engine is quiet and smooth and turning nicely around 3k rpm. 30+ mpg with the AC on and my stereo blasting.

[ICEMAN707]

hmm the 88 lxi tranny sounds good. what about the 89's?

[mouchyn]

i don't know if the ratios are that different between the two -- if at all. i also have an 89 LXi hatch. It feels about the same as the 88. If there are any differences, they're minimal and probably wouldn't affect performance much.

The main thing is to be nice to the synchros. Honda transmissions are notoriously weak in the synchro department. Don't push the shifter into its next gear selection. Let the engine speed fall as you lightly hold it against its next gear. When the engine speed falls to the right spot, the shifter will just slip right into place. This puts relatively no stress on the synchros and yields nice smooth shifts. My 88 LXi transmission has 187,000 miles on it and it shifts like a warm knife through butter.

[mouchyn]

if you have the tranny out of the car (obviously if you're swapping it in), it's not a bad idea to replace the synchros. it's not hard if you have a shop manual printed out. You can buy replacement synchros from honda or a local transmission shop. They're just brass gears, basically.

[ICEMAN707]

you think there are such thing as stronger syncros i could buy?

[mouchyn]

for the 3G accord tranny? doubtful. you might be able to find some out on the web someplace, but they are hard to come by -- even for newer transmissions.

remember: stronger synchros = harder shifts.

you can't have a nice soft synchro that will last longer than the stock unit. does that make sense? if the synchro is "stronger" or "harder," you will have to rev-match your shifts more precisely to keep the gears from grinding. this could potentially yield jerky shifting. sure your gear wouldn't grind as much, but the movement of the shifter would be jerky and racecar-like.

[ICEMAN707]

hmm i've never driven a 5 spd 3gee before. i've driven other cars with hydro trannies. i'll take your advise about the shifting then. thanks!

where did you get your flywheel from?

[mouchyn]

hmm i've never driven a 5 spd 3gee before. i've driven other cars with hydro trannies. i'll take your advise about the shifting then. thanks!

where did you get your flywheel from?

hydro or clutch cables -- there isn't any difference in shifting techniques. hydro or cable jsut refers to how the clutch disc is moved. The tranny internals are the same.

my flywheel is a lightened stock unit. I did the machine work myself and had it spin balanced to 15k rpm. Even with the mild 15lb fly, the car revs up and down WAY faster than stock. I find myself mis-shifting and having to goose the throttle because it revs down so fast, now.

[ICEMAN707]

is there a risk of redlining if you use a 5 lb aluminum flywheel?

[mouchyn]

is there a risk of redlining if you use a 5 lb aluminum flywheel?

not if you pay attention ;)

a 5lb fly will seriously affect daily driving. you'll have to rev the engine to damn near 4k rpm to launch from every stop, the engine will spin down super fast, so stalling happens more often, etc.

since it spins down so fast, you have to be quick with your shifts -- but not so quick that you unnecessarily wear the synchros. you have to be pretty learned in rev-matched shifting before you make the jump to a 5lb fly.

long story short, you have to be a damn good driver to not get frustrated driving around with a 5 pounder. I've been racing and teaching precision driving for years and i wouldn't ever put a 5 pounder on my daily driver. the 15 i have is almost too light.

[AccordEpicenter]

i have an 8lb flywheel on a dual diaphram 6 puck clutch. I could daily drive it if i wanted to

[mouchyn]

i have an 8lb flywheel on a dual diaphram 6 puck clutch. I could daily drive it if i wanted to

you could also drive a 2lb flywheel daily if you wanted to. would it have any real advantage over driving a stock flywheel on a daily basis? you shouldn't be redlining gear after gear on public roads, anyway. if you're not driving like an idiot, it doesn't matter how heavy your fly is. you're not racing anyone -- or at least you shouldn't be.

-race car? go as light as you want
-daily driver? go light enough so the engine spins more freely, but not so light you lose hill climbing torque and pedal ease.

FYI -- lighter flywheels negatively affect gas milage. the more revving you do with your engine to get moving and stuff, the more burst fuel you're burning. Not only that, you'll have to step on the gas pedal more to climb those hills on the hiway.

[ICEMAN707]

the ones phrenology is selling are 16 lbs. right? that should be a good weight right?

[mouchyn]

the ones phrenology is selling are 16 lbs. right? that should be a good weight right?

sure. my 15 pounder is perfect for daily driving. plenty of available passing power on the hiway, dont have to rev any higher to launch than a stock fly, hill climbing power is still good in 5th gear, and my gas milage is great.

[ICEMAN707]

i wonder why honda never made them 15 lbs in the first place. there must be some drawbacks. do you think it might be too fragile? can we fit an lsd into the tranny? or is that jdm b20a only for these cars?

[rjudgey]

Well don't get an early Lude transmission from 83-85 they are weaker, and yes syncors are seriously weak on these boxes so take it easy when shifting i can wear out new syncros in less than 10K when using my car for track use, also the best combo is to get yourself a 1st gen teg box, use 1-4th gear from that, and if you are a track car then keep the teg 5th or use another with a high ratio 5th or if you use on on and do a lot of highway miles go with LXI, or Prelude 5th or best one for crusing is A20A1 5th grear. I have two trannie's one for twisty tracks and one for longer sweepy fast tracks, also teg box is best for high revving and drag racing if you spin upto 7-8K teg ratios are spot on, the only LSD thats good is OMP but thats still a clutch type Quaiffe doesn't make an LSD for ours but whether the B16 one would fit or not i don't know their flippin expensive anyways about £600 pounds about $1000 each!!! Also get some race spec bearings put in the box, the main diff bearings aren't great acutally managed to chew one up after a few 150+mph runs apart from that the gears are quite strong and i've not had problems with them failing, use a really good gearbox fluid something thats a little thicker than Honda recommends the std oil they recommend doens't go high enough on the heat rating even using Auto fluid is quite good for high powered engines and boxes that get abused, also change the fluid regularily if being thrashed.

[ICEMAN707]

very good info rjudgey! thanks a bunch!! :rockon:

BTW any of you guys know how the Phantom grip lsd performs? good or bad? Also, anyone ever looked into a b-series lsd fitting our trannies?