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Hi all,
I have a 87 CRX Si with a D16A1 (integra) swap and the 5th gear ratio is just kiiling me.
After doing some searching, I see that any of the 3G 5th gears will work, and I found the ratio for the prelude's 5th and the LX-i 5th, but I can't find what the gear ratio for the DX 5th is.
Can someone help me out?
Thanks so much,
Robin
what's wrong with your 5th gear? don't like the high engine speeds on the hiway?
what kind of gas milage are you getting?
it is the same as LXI. the only diff between EFI and carb trannies are the final ration. they are 4.066 (EFi accord) and 3.866 (carbed accord).
that is the only diff.
Quote:
Originally Posted by mouchyn
Hey thanks guys, I guess I'm not getting the auto reply... I'll have to look into that.
Nothing's really wrong with the 5th gear I have. It has a whine to it, but I guess that is pretty common with the Integra tranny (and maybe in general Honda transmissions with the little "hat")
At 80MPH the tac sits a little above 4krpms and I get about 32-35mpg when I drive 80-85. (I have a 60 mile commute to school (each way) every day) and when it's nice out and I'm in no rush to get home, I drive 70-75, I get more like 37-40MPG.
I'm just looking to get the maximum gas millage I can. Driving about 12,000 miles a semester really makes you look at every dime a little closer.
Plus if I could quite down that whine at all, it'd be nice.
True. Also Lude Si ratios are the same as LXI accord (and final drive i believe) but 3rd 4th and 5th are geared lower (more rpms at the same speed than an lxi or lx or dx)Quote:
it is the same as LXI. the only diff between EFI and carb trannies are the final ration. they are 4.066 (EFi accord) and 3.866 (carbed accord).
that is the only diff.
well, rest assured you're not going to get much better than that. honda's new hybrid cars barely make gas milage that good.Quote:
Originally Posted by buymysoul
That's because they weigh like five million pounds.
If I throw in a better geared 5th gear, that will keep the RPMs down at higher highway speeds say 3200 rpms.
So in addition to my ears getting a break at 80mph, I should be able to get 40mpg with no trouble. Keep in mind my CRX probably weighs 2100 lbs or so...
they didn't put the 5th gear into your car to waste gas. they used that gear ratio because that's what's required for casual driving.
if you go up and down hills, you will either have to step on the gas harder (wasting fuel under load) or you will have to down shift (engine turning faster anyway). the gear that honda selected has chosen to be a balance of usable hiway cruising power and efficiency.
swapping to a lower 5th gear isn't necessarily going to save you on gas.
I have a few things to say to that.
1st off, Honda never put the D16A1 transmission (with this gearing) in this car.
The ZC and other D16As that they put in the 1st gen CRX had a lower final drive than the UDSM integras.
Also, when this engine was manufactured, the speed limit was 55mph. Honda has lowered all the gear ratios across the board to reflect this.
For instance, the G2 GSR integra has the same 1-4 as the Integra type R, BUT the type R has a longer final drive.
The G2 Integra LS has a tighter gear ratio than the G3 LS, but the cars have virtually the same horse power and the G3 comes in a few pounds more. By your logic, the G3 Integra LS SHOULD have a higher fifth gear to help it get up the hills.
Another thing. There is NO reason for my transmission to be at almost it's peak torque for highway cruising. Talk about wasting gas.
Also, by your logic, the cabbed prelude should have a HIGHER 5th gear ratio than the fuel injected model, but it doesn't. It is lower. Which means at highway speeds, it has less power than the Si model. BUT the rest of the 4 gears are virtually identical. (yes I will concede that the FD on the 85 prelude does negate my argument just slightly)
With the accord, even though the gear ratios are the same. The FD on the Fi model is higher, resulting in a higher rpm at highway speeds which gives it more power on the highway. This would hold true even if the cars had the same weight and horsepower.
The real truth is People who buy the "sport" version of cars want a lot of pickup on the highway. Also, to have a tight 4th gear, you have to make 5th a little tighter too, so the transition from 4th to 5th is COMFORTABLE.
And that's what it really boils down to. Comfort and marketing.
I do appreciate your concern for what I'm doing, but Honda has conveniently setup the gearing in their cars where if it will fit and work with other gears, it will be alright.
A fun swap with L3 (G2 CRX) transmissions is to take the Si FD, the ZC 1st-4th and the HF 5th. It makes a pretty nice tranny all around, and Honda never put something like that together...
One last thing. I'm not sure what the horsepower or weight is of an LXi, but I'd wager it has less than 130hp stock and weighs more than an 87 CRX Si.
Based on that alone, I'm sure that 5th gear will get me down the highway better than it would in the car it came out of. Especially since I have a 4.214 FD...
