New LS1 Owners - Newbie Tech - 3.73 Gears and Dyno Question




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Mbueno
04-04-2012, 11:14 PM
Hi everyone, just had a few questions on the gears and a dyno tuning. Okay, i dynoed my 2002 camaro a month ago and got 286 hp. My only mods so far are a loudmouth 1 catback and the slp air lid and i have an A4. Just wondering if these numbers were more or less good cause it seemed kinda low to me but i might just be expecting to much. The dyno was done on a dynojet.

Also, i want to swap out my stock 2.73 gears for 3.73 gears and was wondering if i have to do anything else with the gearing or will it fit with the stock 10 bolt. Im not really fond with gearing so i was hoping someone could shed some light on if i can swap out the 2.73 gears for the 3.73 gears with no problem. And where would be a good place to order 3.73 gears?

And i ordered an TSP ORY pipe and some longtube pacesetter headers and was wondering how much hp would i be around when i get it dynoed and tuned. I was told by a local performance shop that they are able to remove the O2 sensor code for the check engine light and i would be able to pass inspection with a HP tuner. Is that possible? And if it is, will it come out when i get it inspected? Thanks in advance.


Starz T/A 17
04-05-2012, 02:14 AM
286 is in the normal range for an auto, some dynos are higher or lower. At the end of the day a dyno is just a tool, so take it with a grain of salt. Unless your bench racing there are no benefits to being a dyno queen.

If you get 3.73's they will fit in a 10 bolt rear end. But you will need to have your cpu tuned so that your speedometer is correct. Besides that they will work without a problem as long as you get the correct gears made for a 10 bolt. Any of the sponsors should have them in stock-------------------->

With LT's and a tune I would expect around a 15-20 HP gain on a stock car. As far as passing inspection it depends on what your state/ county does for inspection. IF it is just a OBD2 test then having the codes tuned out will allow it to pass. But most states have a visual inspection; so although the CPU will pass when they visually check for the emission equipment (cats, EGR, AIR, etc.) it will fail based on that

ULTIMATEORANGESS
04-05-2012, 05:30 AM
i recommend a better stall over gears or at least in addition too.


Mbueno
04-05-2012, 10:37 AM
Okay thanks guys, and well i have a question for the stall converter. Which one would be a good stall if the car is my daily driver. I need a set up i can live with since i don't really go to the track. It is just for those spontaneous street racing moments. I heard a yank 3600 converter is great for a daily driver. And also, are 3.73 gears good for a roll race as well?

NC98Z
04-05-2012, 10:50 AM
You just got to order the THICK GEARS when you buy your parts. The quietest gear set I've ran so far has been Yukon Gears. So you need a set of 3.73 thick gears and a full install kit. As far as the converter goes 3200-3600 is plenty for a street car. And don't forget to order a tranny cooler when you buy your converter so your tranny will last.

Mbueno
04-05-2012, 02:19 PM
Alright ill keep that in mind. And an install kit is sold seperatley im guessing... Well can't wait for the build to get going :) and a transcooler im not to fond with. Ill look more into it.

Mbueno
04-05-2012, 02:22 PM
286 is in the normal range for an auto, some dynos are higher or lower. At the end of the day a dyno is just a tool, so take it with a grain of salt. Unless your bench racing there are no benefits to being a dyno queen.

If you get 3.73's they will fit in a 10 bolt rear end. But you will need to have your cpu tuned so that your speedometer is correct. Besides that they will work without a problem as long as you get the correct gears made for a 10 bolt. Any of the sponsors should have them in stock-------------------->

With LT's and a tune I would expect around a 15-20 HP gain on a stock car. As far as passing inspection it depends on what your state/ county does for inspection. IF it is just a OBD2 test then having the codes tuned out will allow it to pass. But most states have a visual inspection; so although the CPU will pass when they visually check for the emission equipment (cats, EGR, AIR, etc.) it will fail based on that

Thanks for this great information as well. Really appreciate it.

towerhand
04-05-2012, 07:21 PM
I have a 02 ws6 6 speed and with pacesetter lts and ory pipe, also summit 85mm tb,and maf with a hp dynotune, i am making 353 horse and 362 torque to rear but thats a 6 speed, also my car has 3.73 gears

99fbodyTA
04-06-2012, 07:17 PM
Okay thanks guys, and well i have a question for the stall converter. Which one would be a good stall if the car is my daily driver. I need a set up i can live with since i don't really go to the track. It is just for those spontaneous street racing moments. I heard a yank 3600 converter is great for a daily driver. And also, are 3.73 gears good for a roll race as well?

i hope so because i need a 3500 stall for my cam install

justin hover
04-08-2012, 07:03 AM
I'd ditch those awefull 2.73s then stall it...If you had 3.23s...I'd stall it first. 2.73s are just a horrible gear for performance, sotp, and dd. A stall will give you kick ass performace over gears any given day, but a stalled 2.73 geared car will really only be fun straight line/drag racing. It will be pretty "loose" around town. 2.73s are only good for gas mileage...It was GMs pitch to have a gas friendly ls1..but the sotp is shit...3rd gear lag is the worst, it does feel slower... 3.73s will cure that...then match it with a 3600.

I would agree with a stall first if your ratio was any higher than 2.73s. Some will disagree and alway's vouch for a stall no matter what the situation is, but 2.73s have no place in any ls1s.

usmcpi
04-11-2012, 04:20 AM
Emissions for OBD2 cars require a visual inspection for cats (at least in my state/county). However, most of the places that do emissions on the side, such as car washes, have minimum wage people doing them. How much do you really think they care? The only thing that will really fail you are any check engine lights (which can be tuned out for things such as off road pipe) and a faulty gas tank.