M7 16% Pulley
 

It's been a week now and I love it. Still waiting for the crank pulley. So far I love the enhanced avaliable power.:eek: :eek: :eek:

Thanks a bunch to Eastsidemini for the tips on the install and the post install support:thumbsup: :thumbsup: :thumbsup: :thumbsup:

pulley installed
 

I'm glad it all work out and happy with the mods. Happy motoring:razz:

Anyone know the hp difference of the 15 to the 16%?

I'm contimplating getting a 16 over a 15 and want to know the hp difference.

mdsbrain, you probably won't feel a difference in that 1%. I wasn't too happy with just the pulley until I introduced some less restricted,cold air into the mix.

I have an Alta CAI if thats what your referring to. I was just wondering for the same price if it was worth it to go 1% smaller for the hp.

The supercharger will spin a little faster with the 16% vs the 15% which would mean it's making a little more power. I used the m7 pulley because it is 16% instead of the 15% that everyone else has. It was just to be different,because I knew that both would provide an increase in power.

I love my 16%. The AGS goes on tomorrow...can't wait.

I'm going to do this mod this week sometime, but have not bought a new belt, or a tensioning tool.

Did you use the tool, or a screwdriver to tighten the belt, or did you just put on a new belt?

-Jake

Use the tensioner tool. It is a whole lot easier. As far as the belt goes, seeing as it's already off, might as well put on a new one.

Ordering the tool will set me back another week at least, seeing as my pulley took 17 days to arrive, I'd like to get it done w/in a month. Has anyone used the screwdriver method? If so how difficult (or not) was it?

The car has 5K on it, so I dont think a new belt is waranted yet, unless putting on a shorter one is really that much better.

pulley install
 

try to see if someone has the tools for rent in your area. Do not use a screw driver:cry: you may get hurt or loose your finger. Worst can happen is the screw driver slip while your finger caught between any part. I say do it right or don't do it at all.

I was looking for something to disuade me...that would do it :lol:

Question
 

Modding Newbie here.

Thinking about purchasing the M7 16% pulley in a couple of days. Is it required to install the crank pulley at the time the other is installed? Is it necessary to install a crank pulley at all? From what I've read, if one was to get the 19% pulley, getting a larger intercooler, crank pulley, and other parts is pretty much mandatory. Can someone help me? Thanks!

The crank pulley is HIGHLY optional. Many in the tuning realm still have mixed feelings about the lightweight crank pulleys because they have no harmonic dampener. Many run them, though. Fact is, oversized or not, the loss in rotating mass gives more power to the wheels. It may also give more vibration through the chassis and stress crank components. May. The short is, they are two completely separate mods. One does not require the other. The crank pulley, by its nature [losing the dampener], is probably the more potentially destructive. Definately chat with some of the more knowledgeable tuners before you do it.

Thanks! Any recommendations on who to ask about this?

Sure. Call Alta and/or M7, who both sell them. Also call Helix and/or Webb Motorsports who don't. That should give you the whole picture.

Good idea - called them and got an answer. Thanks a lot for the helpful info. :thumbsup:

What did you learn? And what did you decide?

Basically just asked if it was absolutely necessary to get the crank pulley at the same time I got the reduction pulley and he said that normally people who do the reduction pulley's get the crank pulley at the same time to save labor costs, which is understandable. But it's not necessary or absolutely mandatory to do it. With the 19% reduction one, it's a highly recommended that you change the belt and get a crank pulley. Also asked if it was alright to get it shipped here and have a non-distributor install it and he said of course. Like I said, I'm new to this whole modding thing (only had a CAI on my integra) and not too bright on some of these. Now I'm just debating if it's worth the $140 + S/H and the $250 for installation. :grin:

OK, I'm kind of new, but... I saw a demo scale at one of the vendor tables at Mini Meet West weighing the various manufacturer's supercharger pulleys. Alta's is almost a pound, which is 6oz heavier than the stock pulley. M7's was well over a pound. Others like Mini Madness and Mini Mania have pulleys under half a pound! It seems screwy to put on such a heavy supercharger pulley, and then put on a lightened crank pulley. Wouldn't the increased rotational mass of the heavier supercharger pulley (which spins very fast) counteract the lightening effect of the crank pulley? Seems odd to me...

Jim

Before getting a crank pulley check out Steven Dinan's article on the Dinan website regarding lightweight and underdrive pulleys. It may change your mind.

the moment of inertia and rpm are what count. the energy to change the rotational velocity is proportional to the moment of inertia and the square of the rpm, so, yeah, a pulley with less moment on the SC makes more difference than on the crank. On the other hand, compared to the moment of the entire rotating chain (crankshaft, flywheel belt, alternator, AC pump, SC rotors, gears and water pump), you're talking peanuts.

It all has to do with the diameter of the pulleys in question.There is a huge difference in dropping 6 lbs from a approx 7 inch pulley ( crankshaft ) or a few ounces from a 3 inch pulley ( supercharger ) .The larger diameter is the big factor here . The added benefit I have found with it on my car is the quicker throttle response which makes it a lot easier rev matching during shifting in addition to the apparent quicker acceleration .

Randy
M7 Tuning

P.S I just read what JLM posted while i was composing this and should not have bothered as he said it a lot better than i could have. Thank you JLM