M&H DRs over MT ET Streets?

[BlownAway05]

Seems to be a lot more dedicated drag racers here than the other site I frequent, figured I'd get more input.

I'm thinking about switching over to the 275/45/18 M&H DR. I am currently running the 26x11.5x17 MT ET Street on stock 17x8 bullit wheels.

Reasons for switching: My car rarely sees daily driving, most of the driving is to the track and back, and occasional errands. Tired of hauling the MTs in the trunk and changing them at the track and before the trip home. I don't trust driving the MTs on the street for fear of just hitting damp roads (would never drive in rain). Thinking of going to DRs so I can just leave them on and feel semi-safe doing the occasional errand. Also, once its caged, I'm not sure if I will even be able to fit the two extra tires in the trunk.

What kind of negative effects will I see switching from the 17x8s and MT ET streets to 18x9s and the 275/45/18s (I have 18x9s on the front and keep those on at the track)? The tire weight difference seems to be about 8 lbs each, and the rim weight difference seems to be about 4 lbs each, so I know I will lose some mph. I'm also going to be making my gearing even worse (already bad with the 3.55s, thinking of doing some gears). Looks like I will be adding some side wall, so how will over-all short time be effected? Best 60' on the MT ET streets is a 1.600.

Advice and opinons are appreciated.

 

[stkjock]

i doubt you'd lose much, I've seen those M&Hs pull 1.5x 60s, if your losing at all its the cut in gearing

 

[mikeysgt]

I have some 275/50/17 m/h drag radials up for sale you can mount on your 17's if you're interested. I pull 1.5 60's consistently on them. Haha jk bro. Welcome to the forum!

 

[BlownAway05]

LOL, first two responses are from the people that are on the other forum I am on (AmericanSpeed on mustangforums).

What kind of mph effects do you all think I will see? It would be adding around 12 lbs for each tire/wheel, that seems like a significant amount of rotating mass.

 

[mikeysgt]

I'd stick to the 17's or get the jets or summit stars like I did. Big and little setup for about 400 bucks

 

[stkjock]

LOL, first two responses are from the people that are on the other forum I am on (AmericanSpeed on mustangforums).

What kind of mph effects do you all think I will see? It would be adding around 12 lbs for each tire/wheel, that seems like a significant amount of rotating mass.

I thought the car looked familiar!

my guess would be maybe a few hundredths in ET and tenths in MPH


if your trying to improve your ETs, go smaller not bigger on the rims

 

[Rygen]

I personally would stick with the MT's. I'm going back to MT's (295/45/17) next week now that I burned off my M&H's (325/45/17). I've run both MT's and M&H's, and found the MT's are a stickier tire, unless you really heat up the M&H's. Also, be careful as the M&H's tend to run more narrow than the MT's.

 

[stkjock]

Also, be careful as the M&H's tend to run more narrow than the MT's.

very true! a few guys I know were a bit upset when they got theirs mounted up.

 

[BlownAway05]

The MT ET Streets seem to be very narrow as well (I believe maybe a 9.5" tread width).

The main point of switching over is so that I don't have to bother switching out my tires anymore (leave the DRs on all the time) and can still run the occasional errand and keep a decent amount of safety if the roads are damp, all while keeping the look of having 18" wheels. I still want to go fast at the track, but am willing to sacrifice some go for convience/show.

If I was purely wanting to squeeze every ounce of ET with the current setup, I'd be running slicks on 15" wheels with skinneys up front, but then that leads to more tire changing (I live in an apartment and have a detached parking garage = PITA).

I'm just trying to guage how much they will effect my mph and ET by adding the extra weight and tire height. If it will be dramatic, then I will axe the idea. If it's minor, I can live with it for the convience benefit. Anyone know what the best 60' time has been pulled on the 275/45/18 M&Hs?

 

[don_w]

I personally don't know anyone running 18" M&H's, so I can't comment on them specifically. But in general, the M&H's have a great reputation for hooking very well. And I run them on the street daily and love them.

As far as the size goes, the M&H is 1.5" taller than the M/T, and with stock gearing that may hurt your 60 a little.

 

[stkjock]

I personally don't know anyone running 18" M&H's, so I can't comment on them specifically. But in general, the M&H's have a great reputation for hooking very well. And I run them on the street daily and love them.

Ron runs them......

 

[US-1]

You are going from a 26" tire to a 28" tire. You'll kill the gear ratio. Expect about 4 tenths and 5 mph loss. I switched from M/T 275/40-17 to the M&H 275/50-17 at Ennis last year and went from 11.26 at 125 mph down to 11.60 at 119 mph.

If you have 3.31 gears you will need to install 3.73 gears to get back to the same final drive ratio.

 

[stkjock]

SD really that much of a difference huh? guess I better find a better calculator

looks like a 6% difference in gear from what I saw

 

[US-1]

I left the starting line at 2000 rpm with both sets of tires. Just would not pull that tall tire as quickly. I had to jack the starting line rpm up to 2800 just to get the car back to mid-high 11.20's that day.

This was on a turbo car. Supercharged setup leaves a bit different so it may not be that drastic. I would feel confident saying that 2-3 tenths and 2-4 mph loss should be expected.

 

[Hawgman]

SD really that much of a difference huh? guess I better find a better calculator

looks like a 6% difference in gear from what I saw

Ah, you don't need a calculator. The formula is pretty easy.
Original tire height divided by new tire height times gear ratio will give you your actual gear ratio.

For example. My stock tires were 27.2" tall. I switched to 305/45/18s that are 28.6" tall. I am running 4.10 gears. So...

27.2 / 28.6 X 4.1 = 3.89. So on my current setup, I am running 3.89 gears

 

[US-1]

No wonder mine took a shit. My 3.31 went down to a 3.09. Blah. Oh well......3.73's and a stroker should cure that problem.

 

[*JZ*]

We sell a hell of a lot more M&H drag radials and slicks over M/T's.

They just work better.


Only downfall, M&H isn't recognized by sanctioned drag racing series such as NMRA and NMCA yet.

 

[stkjock]

ok

27.2/28x3.55=3.45

Not such a big difference...

 

[psfracer]

I say go with the M&H 325/45/17 on a 17X9 and gear the car right (4.10s) unless you foresee a huge difference in rwhp in your near future.

In general, you want to go with the tallest tire you can (larger contact patch) then gear accordingly. When I ran the 325 M&Hs on 17X9 wheels with 4.10s, my best 60' time was 1.431. I now run the 325/50/15s and my best 60' is a 1.412.

As Rygen said, I have seen alot of people have good luck with the 295/45/17 M&T Drag Radial as well.

 

[Freaknazty]

i had good luck with the mt's ( 275/40/17's ) 25.7" tire on 17x8 bullets managed 1.55 60ft's but with that being said im swapping to the 325 m&h's on a 17x9.5 rim now