MM6 vs M12 MO' POWAAA'
Thread Starter
Heel & Toe
Joined: Dec 2016
Posts: 20
Likes: 2
MM6 vs M12 MO' POWAAA'
I know there are discussions about the MM6 vs the M12, but none seem to lead me to an answer. So, in real world situations such as roll & drag racing, which transmission ratios work the best? For stock'ish vehicles, we all understand that the higher numerical ratios of the M12 would accelerate faster and should get you to the finish line first. But, with higher horsepower vehicles, I believe that being able to stay in the power range longer without rowing gears constantly, would improve my overall point A to B time.
The main reason I ask is, I have an opportunity to purchase a Level V RPM with the MM6 ratios, but currently have the M12 and don't want to be dissatisfied.
Current power is 656whp @ 6,300 (don't know why so low...previous tuner) with a P1SC1, meth, full exhaust, fordged bottom. Shooting for a D1 upgrade to break into the 700whp range.
Thanks for any real world, I have witnessed this change information on this subject.
The main reason I ask is, I have an opportunity to purchase a Level V RPM with the MM6 ratios, but currently have the M12 and don't want to be dissatisfied.
Current power is 656whp @ 6,300 (don't know why so low...previous tuner) with a P1SC1, meth, full exhaust, fordged bottom. Shooting for a D1 upgrade to break into the 700whp range.
Thanks for any real world, I have witnessed this change information on this subject.
Safety Car
Joined: Apr 2004
Posts: 3,532
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From: pueblo co
i think the mn6 would work better for you ...IIRC the top speed for a stock coupe with the mn6 is 181 and the stock speed with the mn12 was 171...while the mn12 is quicker in a sense shorter gearing as its a close ratio 6 speed...
Race Director
Joined: Apr 2007
Posts: 18,048
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From: long Island NY
You will have longer legs with MN6. Road racing is the reason gears in MN12 are so dam good in the turns. The gears mixed with a great cam and lightweight valve train is why you can take a Z down to 20 mph and stomp on it and it pulls like a freight train. For most of us the gears in the MN6 would be funner to play around and roll race.
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you're making good power so the mm6 gears would benefit you in my opinion... I did a tr6060 swap into my car not long ago with c6z 1st thru 4th gears (same as mm6) and zr1 5th/6th gears and I love it... the car will launch better, each gear will have a higher top speed, you will stay in boost longer, a lot of pluses really... if you have the opportunity you might swap in the 5th/6th gear from the mn12 into the other trans, that will help acceleration in the higher gears... is there a reason they only ran your car to 6300?... maybe out of fuel or they were being safe, I'm just curious
Thread Starter
Heel & Toe
Joined: Dec 2016
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That is that is the question of the century...lol. It is not out of fuel, and actually, I need let the meth do more magic than it currently is so I can reap the benefits. My new tuner is well known in our area for his ability to bring every ounce out of an LS car and he is going to turn the limiter up when I hit his Mustang dyno.
I never thought about the 5th & 6th swap, thank you for reminding me of that.
I do believe the ratios of the MM6 will be beneficial.
I never thought about the 5th & 6th swap, thank you for reminding me of that.
I do believe the ratios of the MM6 will be beneficial.
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what fuel setup do you have?... is the rev limiter actually set at 6300 or did they only rev it to that rpm on the dyno?... what size blower pulley and stock or overdrive balancer?... maybe they were trying to keep you from overspinning the blower is why I ask... if you have enough fuel and the blower isn't maxed I don't see any reason why you couldn't spin up to 6800 and that alone would pick up some power
Thread Starter
Heel & Toe
Joined: Dec 2016
Posts: 20
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BAP with 60# injectors (fuel pressure holds strong), stock balancer, 3.85 pulley, and I have roughly 14,000 rpm left before max. The car is running a bit rich. I have tried to talk to the previous tuner, a well known shop in close to Atlanta, with no response on their end. I have also spoken to the engine builder and he is baffled at the 6,300 rpm limit.
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I had a setup similar to yours in the past, 255 pump, bap, 60lb injectors, meth, and made 720ish with no issues and you mentioned you have meth so I think it should be fine once tuned properly but any more than that you should probably build the fuel system... I ran 100% meth and that's what I suggest if you are using it to make more power... sorry I didn't mean to derail your thread