Ok guys the time has come to swap my auto tranny out for a manual one. I have found a tranny from a d16y7 for a great price and its local so I could just pick it up. I believe this is what I will do but I would like to find out some info first because from searching I know that there is a difference in the gearing between the y8 and y7 trannys.

1. Would it be better to use the d16y8 tranny since I have a d16y8 motor?

2. Which of the two trannys is better for quick acceleration?

3. Which of the two trannys is better for gas maileage?

Pretty much, I'm just wondering which one I would be better of using. If I will be ok with the d16y7 tranny then thats great. Thanks in advance for any input and advice.

 

BUMP!

 

1. its up to you.
2. the y8 tranny is going to be better for acceleration.
3. the y7 is going to be better for gas mileage.
over all there isn't too much of a difference.
Here is a link to NOFX's post... on the first part you can see the differences to the y8 tranny and the y7.

https://honda-tech.com/zerothread?id=2055230

 

Thank you sir.

 

Ok so the only difference in the two is in second and third gear and the difference is minimal. I will go with the d16y7 tranny. Thank you again. Thread ended.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iluvmy2000civicex &raquo;</TD></TR><TR><TD CLASS="quote">Ok so the only difference in the two is in second and third gear and the difference is minimal. I will go with the d16y7 tranny. Thank you again. Thread ended.</TD></TR></TABLE>

Actually the difference is pretty big - and will pretty much decide a race in equal powered motors.

And not only is the Y7 geared a bit more speed instead of accel in 2nd and 3rd, but it also has A LOT taller of a final drive - making all the gears taller.

What do I mean?

Y7:
In 2nd gear the Y7 will peak at 744ft-lbs tq. at the axle.
In 3rd gear the Y7 will peak at 489ft-lbs tq. at the axle.

Y8:
In 2nd gear the Y8 will peak at 868ft-lbs tq. at the axle.
In 3rd gear the Y8 will peak at 568ft-lbs tq. at the axle.

Okay, fine, makes sense, the Y7 is the weaker of the two.

Now, calculate a Y7 trans on a Y8 motor:
In 2nd gear the Y8 will peak at 773ft-lbs tq. at the axle.
In 3rd gear the Y8 will peak at 508ft-lbs tq. at the axle.

That's a 95ft-lb difference in 2nd and a 60ft-lb difference in 3rd between the Y7 and Y8 transmissions on a Y8 motor.

Now dynos won't give you numbers at the axles - they'll strip away power added by the trans - so I'll use a percentage just to make my point:

A Y8, with the Y7 trans is 12.3% loss in tq. in 2nd and an 11.8% loss in peak tq. in 3rd.

Those Y8 ratios add up, the Y7 has longer gearing all around due to it having a taller rear end - and as you can see, you lose quite a bit in 2nd and 3rd, and still lose 4.5% ft-lbs tq. and HP in 1st, 4th, 5th, and reverse.

 

Damn now thats the kinda stuff I was looking for. Thank you Syndacate. Since the main reason I'm looking to do this is to add some pep to my d16y8 I guess I should do it right or not do it at all. I will search around for a d16y8 tranny and if one is not attainable I will settle for the d16y7. Do you think that it is really that much of a difference in torque and power to go through the extra trouble for? Thanks again.

P.S. I kinda laughing because of you mentioning the loss of torque and power in reverse haha but I see what you were saying.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iluvmy2000civicex &raquo;</TD></TR><TR><TD CLASS="quote">Damn now thats the kinda stuff I was looking for. Thank you Syndacate. Since the main reason I'm looking to do this is to add some pep to my d16y8 I guess I should do it right or not do it at all. I will search around for a d16y8 tranny and if one is not attainable I will settle for the d16y7. Do you think that it is really that much of a difference in torque and power to go through the extra trouble for? Thanks again.

P.S. I kinda laughing because of you mentioning the loss of torque and power in reverse haha but I see what you were saying.</TD></TR></TABLE>

Due to how high the loss of power is in auto trans's, you should notice more pep with the Y7 man trans. Though I'd do like you said, look for a Y8, dig for a Y8, and if all else fails you can settle on a Y7.

The difference is definitely noticeable when u drive both..and a Y8 isn't all that fast to begin with.

So I do believe it's worth the trouble, others may not agree. I mean a trans' swap is going to be the cheapest way (in ur current situation) to add power to ur car - might as well drop an extra 1 or 2 hundred for the extra power - it'll be the best bang for your buck you can get in ur current situation with a D never again will you see that much gain for ur cost, if ya see what I mean.

 

Yea thats what I'm thinking to. Money is not the problem although I like to save money where I can. This is my daily driver so I don't want to swap it or turbo it (especially with the auto tranny haha). So I figure this will be my most effective way to gain some power. And since I will be doing the work myself with maybe the help of a friend, my only expenses will be for the parts so I think I can come out of it pretty cheap.

I'm going to start looking for a d16y8 tranny and if it is not attainable I will go with the d16y7 tranny and be happy. Either way I have some questions as far as the swap is concerned such as what parts will be needed and things like this but I think I will just start i new thread for this.

Thanks again for your help. Any additional comments you have are welcome.