Gears

**seth_12** · 10-21-2009, 03:43 PM

Does anyone out there run 410s or 391s gears in their Trans Am? I'm trying to see which one of those would be better for low end and top end...let me know if you know anything about gears.

**Hi-Po** · 10-21-2009, 04:08 PM

Are you a manual or automatic? 4.11 work great in a M6 car, you will lose a tad of MPH way up top but you will get to that speed quicker

**seth_12** · 10-21-2009, 04:09 PM

my car is an automatic

**Hi-Po** · 10-21-2009, 04:11 PM

Originally Posted by seth_12

my car is an automatic

4.11 would leave you screaming on the express way. Scratch that idea if this is a DD. The auto guys like the 3.73 gear ratio.

**seth_12** · 10-21-2009, 04:17 PM

yea it is a daily driver but i have 342s in my car and i was told that there is not much of a difference between 342s and 373s just bumps it up about a few 100s in the rpm range...thats why i was thinking maybe just 391s my buddy has a z28 camero and has 411s in his and its auto and he is about a little bit above 3 grand on the rpms crusin at about 70 on the hwy.

**Hi-Po** · 10-21-2009, 04:21 PM

Originally Posted by seth_12

yea it is a daily driver but i have 342s in my car and i was told that there is not much of a difference between 342s and 373s just bumps it up about a few 100s in the rpm range...thats why i was thinking maybe just 391s my buddy has a z28 camero and has 411s in his and its auto and he is about a little bit above 3 grand on the rpms crusin at about 70 on the hwy.

IMO, thats high for 70. But I usually cruise at 80ish. If I was auto, I would be tempted to put 3.90's in. If your go the the 1/4 mile track, you might wanna play around/search around for information on gears vs tire sizes. A taller tire will make up for a steeper gear.

If I went to a 4.30 gear, I would be coming very close to having to shift into 5th. Thats a no-no. See where im going with this? I would get a different stall, 3.73's and a different camshaft. If I was auto

**seth_12** · 10-21-2009, 04:31 PM

i have a cam in mine so you think i should stick with 373s the car is pretty fast as it is for just having 342s in the rear end

**Hi-Po** · 10-21-2009, 04:35 PM

Originally Posted by seth_12

i have a cam in mine so you think i should stick with 373s the car is pretty fast as it is for just having 342s in the rear end

If you have the money, and don't mind dropping money into a rear end that will undoubtedly break on you... absolutely. It will help, there's no way around it. If you think you can handle a higher RPM on the expressway, you can go that route also.

Or, ride to work with your buddy for a week and feel his car with 4.11/auto/cammed

**seth_12** · 10-21-2009, 04:40 PM

lol i would ride in his but that idiot blew his transmission bc he is a hardass and always puts it in 1st gears and does all kinds of crap...i leave mine in drive and i dont hardly ever rag on it

**Hi-Po** · 10-21-2009, 04:52 PM

Originally Posted by seth_12

lol i would ride in his but that idiot blew his transmission bc he is a hardass and always puts it in 1st gears and does all kinds of crap...i leave mine in drive and i dont hardly ever rag on it

Well, Good for you, let that automatic shift itself. Its hard to tell you if you should go with a steeper gear then 3.73. I dont know what your tolerances are for certain annoyances. Plus, Im not an automatic, so its hard for me to really give you any great information on it. I think your on the right track, ask around and keep searching before you make your decision.

**666ws6** · 10-21-2009, 05:16 PM

I'm an A4, and put in 3.90's. (3500 stall an 228R cam) I don't think hwy speeds at 80 are too bad. I think I hover around 2500-2600 rpm when doing 80. The car ran good at the track too... 12.5s. Tougher to stick the rear, and lost some top end, but gained it low. I would recommend 3.90's even with a DD, but it may depend on your entire set-up.

**seth_12** · 10-21-2009, 05:35 PM

well what do you top out at it before you have to shut it down?

**Z28Thunder** · 10-21-2009, 08:51 PM

Okay quick setup info for mine here. Headers,4000 TCI custom,231/237,3.73's. 11.52's all day everyday in track trim (full slicks). 11.8's to 11.7's on street DR's. I run 2300/2400 rpm at 80. It all depends what your willing to put with on the street. I like to DD,Cruise,Road Trip and Track. I am at that fine line IMO. I would love to push towards the 10's and have the heads to put on it if I want. I also have nitrous if I want to go the route. But right now I enjoy that I can DD and not have issue. Will loping sitting at the light. The looks make it worth it.. Well that and a manual fan switch.

**Hi-Po** · 10-21-2009, 09:27 PM

Originally Posted by Z28Thunder

Okay quick setup info for mine here. Headers,4000 TCI custom,231/237,3.73's. 11.52's all day everyday in track trim (full slicks). 11.8's to 11.7's on street DR's. I run 2300/2400 rpm at 80. It all depends what your willing to put with on the street. I like to DD,Cruise,Road Trip and Track. I am at that fine line IMO. I would love to push towards the 10's and have the heads to put on it if I want. I also have nitrous if I want to go the route. But right now I enjoy that I can DD and not have issue. Will loping sitting at the light. The looks make it worth it.. Well that and a manual fan switch.

You forgot to mention what gear your running

**Cutlass** · 10-22-2009, 09:43 AM

Originally Posted by Hi-Po

You forgot to mention what gear your running

nope, you missed it. Its 3.73s

**Hi-Po** · 10-22-2009, 09:54 AM

Originally Posted by Cutlass

nope, you missed it. Its 3.73s

Damnit! I probably read that 4 times

Thanks

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**seth_12** · 10-22-2009, 10:59 AM

Originally Posted by Z28Thunder

Okay quick setup info for mine here. Headers,4000 TCI custom,231/237,3.73's. 11.52's all day everyday in track trim (full slicks). 11.8's to 11.7's on street DR's. I run 2300/2400 rpm at 80. It all depends what your willing to put with on the street. I like to DD,Cruise,Road Trip and Track. I am at that fine line IMO. I would love to push towards the 10's and have the heads to put on it if I want. I also have nitrous if I want to go the route. But right now I enjoy that I can DD and not have issue. Will loping sitting at the light. The looks make it worth it.. Well that and a manual fan switch.

Did you ever had to cali. your speedometer when you put 373's in the rear end?

**666ws6** · 10-22-2009, 01:10 PM

Any time you change from stock to a different gear you will need to recalibrate your speedo.... or learn what your speed and rpm differences mean.

**Hi-Po** · 10-22-2009, 01:21 PM

Originally Posted by seth_12

Did you ever had to cali. your speedometer when you put 373's in the rear end?

You will definitely have to calibrate the speedometer. Its not a big deal, it can be done with most handhelds or HPT.

**seth_12** · 10-22-2009, 05:49 PM

dang all this gears stuff confuses me i still gotta decide if im gonna get 373 or 391 but the guy that's doing my rear end told me that there is not really a big difference between 342 and 373