Rear Gear Ratio

CJME · 09-28-2015, 02:32 AM

I run a 68 camaro with an M22 trans and a 4.56 rear gear. With 28" tires i either bog the engine at launch or burn the tires off. What rear end gear do you guys recommend with this combo? i was thinking 5.38. Engine is a 12.5:1 332 and the car weighs 3000lbs.

Geerhead55 · 09-28-2015, 12:57 PM

I can only speak for myself,, but back in the day,, I ran a '66 Nova SS, that was over 3,000lbs with me in it. It had a 331/ 4-speed combo with a 10.5x 29.5 tire. I started out with 4:88s and eventually put 5:57s in it. I'd launch at 7,300- shift around the same and go through the top end at 7,600. This was with 'ol Lakewood traction bars, Moroso front springs and 90-10 shocks, as that's all we had. It pulled 'em up in 2 gears and was a fun ride! I know technology has come a long ways since the '70s, but its still basic math finding what the car likes. You've got to get it to hook first, consistently, before you start playing anymore. Put a good slick under it and work your suspension.Good luck with your project.
Danny Durham

CJME · 10-15-2015, 10:19 PM

I run MT 28/11.5/15 ET streets and i'm soon changing to Hoosier slicks 28/10.5/15. The 2.20 first gear of the M22 is killing my 60 ft. There are two options i'm considering: Changing trans to a 2.88 first gear or change rear end gears. Which do you guys recommend from experience?

Jeff Stout · 10-16-2015, 11:56 AM

My old 70 Chevelle with 355 had 5.13 and 2.88 first with 50 lb flywheel. I would leave at 4000 and it would hook very well and not bog but drive through first pretty good. This was back in 1995 so Im sure its not whats best today

Mike Pearson · 10-16-2015, 12:36 PM

You will only get a handful of runs with that Muncie once you put a lower gear in the rear. I would put a 5.57 to start with. Put a Jerico trans with a 3.10 low gear. Also you want a light flywheel. I ran a 14 lb. wheel in my car years back. it was much faster than the 25 lb. wheel. With a stick car you want some wheel spin to keep the RPM up and the breakage down.

tj310 · 10-18-2015, 05:30 PM

In our 305 J/S it's gone quicker every time I've put more rear gear to it , 6.0 now .. A good trans ( Liberty ,G force , Jerico ) and a slipper clutch will save money and aggravation in the long run. ---Trevor

09-28-2015, 02:32 AM	#1
CJME Junior Member Join Date: Sep 2015 Location: Quincy Illinois Posts: 5 Likes: 0 Liked 0 Times in 0 Posts	Rear Gear Ratio I run a 68 camaro with an M22 trans and a 4.56 rear gear. With 28" tires i either bog the engine at launch or burn the tires off. What rear end gear do you guys recommend with this combo? i was thinking 5.38. Engine is a 12.5:1 332 and the car weighs 3000lbs.

09-28-2015, 12:57 PM	#2
Geerhead55 VIP Member Join Date: Sep 2002 Location: Tacoma, Washington Posts: 1,632 Likes: 0 Liked 5 Times in 5 Posts	Re: Rear Gear Ratio I can only speak for myself,, but back in the day,, I ran a '66 Nova SS, that was over 3,000lbs with me in it. It had a 331/ 4-speed combo with a 10.5x 29.5 tire. I started out with 4:88s and eventually put 5:57s in it. I'd launch at 7,300- shift around the same and go through the top end at 7,600. This was with 'ol Lakewood traction bars, Moroso front springs and 90-10 shocks, as that's all we had. It pulled 'em up in 2 gears and was a fun ride! I know technology has come a long ways since the '70s, but its still basic math finding what the car likes. You've got to get it to hook first, consistently, before you start playing anymore. Put a good slick under it and work your suspension.Good luck with your project. Danny Durham Last edited by Geerhead55; 09-28-2015 at 01:02 PM.

10-15-2015, 10:19 PM	#3
CJME Junior Member Join Date: Sep 2015 Location: Quincy Illinois Posts: 5 Likes: 0 Liked 0 Times in 0 Posts	Re: Rear Gear Ratio I run MT 28/11.5/15 ET streets and i'm soon changing to Hoosier slicks 28/10.5/15. The 2.20 first gear of the M22 is killing my 60 ft. There are two options i'm considering: Changing trans to a 2.88 first gear or change rear end gears. Which do you guys recommend from experience?

10-16-2015, 11:56 AM	#4
Jeff Stout VIP Member Join Date: Dec 2001 Location: phoenix Posts: 1,489 Likes: 66 Liked 706 Times in 283 Posts	Re: Rear Gear Ratio My old 70 Chevelle with 355 had 5.13 and 2.88 first with 50 lb flywheel. I would leave at 4000 and it would hook very well and not bog but drive through first pretty good. This was back in 1995 so Im sure its not whats best today

10-16-2015, 12:36 PM	#5
Mike Pearson VIP Member Join Date: Mar 2007 Posts: 2,462 Likes: 620 Liked 1,948 Times in 589 Posts	Re: Rear Gear Ratio You will only get a handful of runs with that Muncie once you put a lower gear in the rear. I would put a 5.57 to start with. Put a Jerico trans with a 3.10 low gear. Also you want a light flywheel. I ran a 14 lb. wheel in my car years back. it was much faster than the 25 lb. wheel. With a stick car you want some wheel spin to keep the RPM up and the breakage down. __________________ Mike Pearson 2485 SS

10-18-2015, 05:30 PM	#6
tj310 Member Join Date: Sep 2009 Location: Dresden On. Canada Posts: 460 Likes: 0 Liked 0 Times in 0 Posts	Re: Rear Gear Ratio In our 305 J/S it's gone quicker every time I've put more rear gear to it , 6.0 now .. A good trans ( Liberty ,G force , Jerico ) and a slipper clutch will save money and aggravation in the long run. ---Trevor