Drive Accord Honda Forums banner

1 - 12 of 12 Posts

·
09 EX-L V6 Nav Coupe
Joined
·
266 Posts
Discussion Starter #1
In a comparison between a 2004 Pontiac Grand Prix GTP and an 08 Accord V6 there's a Pontiac guy saying our "weak" Japanese engines need high gearing to move and that our gear ratio is 4.31 whereas the GTP's is a taller 2.93. These are the final drive ratio's.

Now I don't totally understand exactly how gearing works gear-to-gear but I assume there must be more to it then this. To me this car seems to have steep ratio's and I always felt its often slow to get into the power. I assumed Honda did this for reliability and gas mileage reasons. Also, these auto's are slower to 60 and down the 1/4 mile then most other cars with similar power and weight, so I can't see how we have aggressive gearing.

Any gear experts, so to speak, who can explain this better?

*** Link removed by Mod, no street racing material allowed ***
 

·
Registered
Joined
·
18 Posts
I recently took my 2008 Accord V6 Ex-L Coupe into the dealer because it felt like the tranny was slipping. I have 38,XXX miles on it. The tech and I went for a drive and he mentioned a couple things. One, many people have come in to complain about the tranny and how they thought it was slipping or shifting hard. He also mentioned that Honda has programmed the tranny to stay in a higher gear longer as to get better gas mileage. That is why sometimes it feels like it's jerking or "slipping". They did a computer analysis of my tranny and sent it to Honda. Honda replied, told them to make sure that my ecu was updated and that everything was fine. I don't think that our gears are more aggressive, to me it seems that they stay in a higher gear longer as to get better mpg.
 

·
Registered
Joined
·
1,276 Posts
are you guys referring to the sometimes lag time between gunning it and finally responding?? like the pull back is the same as the jerk you feel? if so, when i test drove accord cars, it i felt it more in the 4 banger..
 

·
09 EX-L V6 Nav Coupe
Joined
·
266 Posts
Discussion Starter #4
No, I'm just talking about the gearing....it always felt like it had tall gearing. If you have lower gearing you get into the power faster.
 

·
Registered
Joined
·
1,675 Posts
Accord Auto:
1st: 2.697
2nd: 1.606
3rd: 1.071
4th: 0.766
5th: 0.538
Reverse: 1.889
Final Drive Ratio: 4.31

Grand Prix 4T65-E
1st: 2.921
2nd: 1.568
3rd: 1.00
4th: 0.705
Reverse: 2.385
Final Drive Ratio: 3.05

However, the 2008 V6 also has 68hp and 18 ft/lbs of torque over the GT (not GTP). I'd say the reason for the higher ratio is due to the increased weight of the 8th gen, not because of a lack in power.
 

·
09 EX-L V6 Nav Coupe
Joined
·
266 Posts
Discussion Starter #6
I accidentally initially wrote GT, but its a GTP, I edited the post. The GTP weighs about 3600 lbs I think so it's even heavier the the accord coupe, although not all that much heavier.
 

·
Registered
Joined
·
1,276 Posts
you guys go to the dealership to update your ecu often??? I didn't know about this...is this something that needs to be done every year or so?
 

·
Registered
Joined
·
1,675 Posts
you guys go to the dealership to update your ecu often??? I didn't know about this...is this something that needs to be done every year or so?
Gear ratios can't be changed with a computer, they're simply the ratio between two physical gears in the transmission.

And I see, you might want to ask the guy why the Comp G package bumps the final ratio up to 3.29 lol. In any case, at least our engines don't catch on fire like an L67 :lmao:
 

·
Registered
Joined
·
3,126 Posts
Final drive ratio is only half of the equation . To find out total ratio for each gear you simply multiply gear ratio and final drive .

example for first as posted specs above

Accord Auto:
1st: 2.697
2nd: 1.606
3rd: 1.071
4th: 0.766
5th: 0.538
Reverse: 1.889
Final Drive Ratio: 4.31

Grand Prix 4T65-E
1st: 2.921
2nd: 1.568
3rd: 1.00
4th: 0.705
Reverse: 2.385
Final Drive Ratio: 3.05

So accord first gear total ratio is 2.697 * 4.31 = 11.62
Accord top gear (5th) total ratio is 0.538 * 4.31 = 2.31

Grand Prix first gear total ratio is 2.921 * 3.05 = 8.90
Grand Prix top gear (4th) total ratio is 0.705 * 3.05 = 2.15
Go down and multiply all gears with final drive will give you total ratio for each gear . For first the Accord is much lower geared and top gear is only slightly lower . Also remember your comparing 4 speed to 5speed , Accords 5 AT has 2 overdrive gears (4 an 5th ) .
 

·
Registered
Joined
·
2,953 Posts
In a comparison between a 2004 Pontiac Grand Prix GTP and an 08 Accord V6 there's a Pontiac guy saying our "weak" Japanese engines need high gearing to move and that our gear ratio is 4.31 whereas the GTP's is a taller 2.93. These are the final drive ratio's.

Now I don't totally understand exactly how gearing works gear-to-gear but I assume there must be more to it then this. To me this car seems to have steep ratio's and I always felt its often slow to get into the power. I assumed Honda did this for reliability and gas mileage reasons. Also, these auto's are slower to 60 and down the 1/4 mile then most other cars with similar power and weight, so I can't see how we have aggressive gearing.

Any gear experts, so to speak, who can explain this better?

*** Link removed by Mod, no street racing material allowed ***
You can't just go by gear ratios, whether they are the ratios in the differential, ratios in the transmission, or final drive ratios. Manufacturers take into account engine, transmission (auto or manual), number of transmission gears, vehicle weight, gas mileage, towing, and a bunch of other parameters when deciding on gear ratios. You can't compare two different cars, and you can't compare two of the same car if there are big differences (I4/V6, auto/manual tranny, FWD/AWD, etc.). If you want a more in-depth explanation of why read on...

Generally speaking, the higher numerically the gear ratio, the faster the acceleration, the lower the top speed, and the worse the gas mileage. Anything under 1.00 is overdrive. It's not as simple as that and you can really only compare two identical vehicles by only changing one variable.

For example, when I had my S10 I added a LSD and changed the rear gears from 3.08 to 4.10. After calibrating my speedometer, my RPMs at any given speed were much higher. The truck accelerated much faster and it was much easier to pull a trailer, but gas mileage went down (higher RPM at cruising speed) and the top speed was lower because redline in 5th gear came at a lower speed than before. The 4.10s were a little much and I swapped them out for 3.73s.

I said generally speaking because if you change things like tire diameter, it also affects the car. Think of lifted trucks that run say a 31" tire stock but a 38" tire with a lift kit. The large tires have fewer revolutions per mile and it feels like the truck is running a much higher (lower numerically) gear ratio. The truck will feel like a dog and gas mileage usually suffers because you are constantly giving it much more gas to get moving and up to speed. If you do a gear swap that brings the speedometer accuracy back (say 3.08 to 4.10 or 4.33 or whatever), the lost performance will come back and you can accelerate normally. That's why I always try to convince people to swap front and rear gears (and add lockers while they have the diffs apart) when they lift trucks, but they usually balk at the additional $3k or so on top of what they paid for the lift, wheels, and tires. The added cost is one of the main reasons my truck is stock height.

It gets even more complicated when you add in AWD or especially 4WD when the transfer case has 2WD high, 4WD high, and 4WD low.
 

·
Registered
Joined
·
3,126 Posts
you can compare gear ratios but if you think its going to tell you performance its not unless you compare same engine and chassis .
One reason many imports have higher final drives and lower low gear ratios is because were the max TQ (how much) is in powerband .Many imports are geared towards high TQ peak in the rpm powerband, look at Honda its at 4500-5000 rpm . many of domestic makes of V6 an V8 have more TQ at lower rpm . .So they don't need lower gearing as much to accelerate off the line . This aspect has been changing in last few yrs and now many domestic makers engines have also moved peak rpm and TQ up (mustang's , Camaro's etc) .Higher the peak TQ the more HP the engine is all other things being the same .

One other thing IMO is cause for higher final drives in import FWD . FWD have limited space for its transmission and in general to have high strength its better to have 1 higher final drive ratio in the FWD section than to try and do it at each gear . This helps space and strength , keeping a small package were width size is a issue .
 
1 - 12 of 12 Posts
Top