Over the weekend I had a chance to stop by Steve's Auto Clinic for the install party and decided to have the M7 throttle body installed while I was there.

I'd compare it to receiving your car with a throttle body the size of a straw and then replacing the throttle body with one the size of a fire hose. Ok. Maybe not the best example, but what a change in performance...this thing really brought the car alive. UNBELIEVABLE!

 

Good to hear AMPR! Peter has been doing TBs for sometime now. Do you know what size you got? 61 and 62mm seem to be the most popular, but there are some 63's...

 

your right, it is unbelievable

 

Tony,

I believe it's a 62mm. And what a difference. They say a picture speaks a thousand words and if I could have only taken a picture of the look on Steve's face after he came back from test driving it.

Anyhow, if you haven't done so I would highly recommend it to anyone who's thinking about it.
AMPR

 

a what's up guys, Peter was telling me about this. I'm going down there next week, hopefully I can check one out somewhere.

What did he do? Replace the stock throttle body? Anything else?

 

Is there a price for this TB ?
Also being someone who cant go and drop in on Peter, is it a fairly straight forward changeover?? :smile:

 

Gosh, don't hold me to the price, but I believe M7 TB's are 299 bucks. If I'm mistaken, then it's probably 399...

Heck, the switch-aroo can be as fast as 20 minutes with previous experience, and maybe 45 min to an hour for the first-timer. It's very easy, and certainly qaulifies as a DIY...

 

I know who Ill want around when I get one

 

AMPR - what other mods do you have? I'd imagine that in order for a throttle body to produce noticeable gains, you'd have to have a pretty heavily modded car. Certainly an intake, exhaust and pulley but more than likely I would think a head, header and larger injectors would also be necessary. Dynos have shown that with intake, exhaust and pulley, a throttle body only makes 1 or 2hp. Could throttle response be greatly improved? I suppose so.

 

Greatgro, since I do have a few odds & ends I could feel the increased throttle response immediately after having the new TB installed.

 

Which odds and ends? That's what I was interested in. :smile:

 

does the price of the throttle body include a core charge?

 

It makes sense that a bored-out throttle body would improve "throttle response" even in an unmodded vehicle, since the same throttle angle is allowing a larger air gap between the butterfly and the sides. What remains to be seen is how the actual flow and/or actual pressure drop across the throttle body is affected in real world operation.

 

The price on the throttle bodies are $ 399 plus a $ 200 core charge at this time.
We have 61 mm in stock for the Cooper and 61,62 and soon 63 in stock for the S.
Randy

team M7
www.M7tuning.com

 

i'd like to do the throttle body eventually. what are the advantages/disadvantages to the different sizes? does each one have it's own different performance characteristics? i know Helix and Madness have been using 63mm, but Dinan just came out with their 60mm. although i trust Helix and Madness' judgement it seems like Dinan with all their $$ and research found the smaller size to be sufficient enough any comments? which size is better suited to what needs?

 

Greatgro,

The odds & ends are:

15% Alta Pulley
K&N CAI
Borla Race
M7 62MM TB
M7 Plasma Booster
M7 Sway Bar Links
Bilstein PSS9's
Eibach Sways

and a few other non performance enhancing odds & ends

AMPR

 

AMPR,
Thanks. I always like to see what mods a person has when they review a new product.

 

Fluid dynamics is a lot more complicated than simply picking a diameter. If they're being modified in different ways, its possible to get the similar performance from different sized TBs. If you can reduce the restriction without increasing the diameter, you're not losing any velocity through the TB (better).


--
Cheese

 

I agree with Mr. Cheese. 100%
Charles

 

so in what ways are these companies modifying the TBs, and how do their methods differ?

 

I'll spill the beans...
drill out the peened over ends of the torqx bolts holding the butterfly to the shaft (don't FU the shaft with any scratches);
cut off the aluminum compression band to get at the interior. ;drive out the drift preventing the shaft from slipping out;
cleverly figure out how to unload the return spring, remove the screws holding the butterfly to the shaft, slip out the bfly, slip out the throttle shaft and intermediate gear. (of course you noted the correct gear mesh configuration and return spring trickery. (don't FU the tiny wipers that read the position pot)

make a jig plate to bolt the body to, set your position by dialing in the existing bore to within .000", rough out the bore to .030 of final size, then finish bore to size. deburr the edges. Of course you used some protection so funk wouldn't get into the needle bearings or the electronic mechanisms;
measure the resulting bore to .001";
prepare bfly blanks from .100 thick aluminum with two holes matching the shaft bolt postions;
make a jig plate to hold new bfly blanks at 7degrees off horizontal, mill the OD to the size of the finished bore less .002. deburr and file tiny flats about .015 at the shaft diameter positions;
trial fit the bfly to the bore; remember it's an ellipse, so it has to be oriented or it will jam and scratch your nice finish;
install the flywheel, using your clever method to disable the springs and maintain the correct gear and postions stop arrangement;
fit the torqx screws gentlyto center the bfly and check for free movement; lockticht and tighten the torqx bolts;
re-insert the drift (not so easy);
figure out a way to band clamp on the electronics cover;

no sweat. eh?

63 mm is about the max you can get away with as far as wall thickness.

Cheese would add a step by airfoiling the edges of the bfly and streamlining the shaft...

 

WHOA!!

thanks, jlm.

 

JLM Great explanation , you have been here before. The real difference we are seeing with the other TB's and ours is in two major areas. One the actual surface left after the enlarging process and the second is the fitment of the throttle plate itself and the all important shape of the edge. We go to great lengths making sure the surface is as smooth as possible and it is noticeable to the naked eye as well as touch.As for the shape of edges of the plate that was derived from several hours on the computer to come up with a shape that maintains its constant clearance even though the angle is changing. In the past many larger throttle bodies had a hard time idling properly and required a lot of re clocking of the internal gears. With our current throttle plate we are now able to just bolt it on and get a immediate idle to our specs within +/- 50 RPM. One more last area we feel we are doing as well as anyone and better than some is the way we re attach the cover after the modifications have been made. We are able to make the stock aluminum band work again which provides a superior fit to the other methods. A case in point is one of our new customers came by the last Steve's/ M7 install party and had a throttle body which had been installed by the dealer not 24 hrs before. Their method of re attaching the cover was with electrical tape The tape had come undone and needless to say the owner was slightly miffed as we were helping him get it back together so he could return to the dealer and give him a piece of his mind. I won't say who the other manufacturer was but it begins with D One last note I had given the size of the TB for the cooper as being much larger than it is. The stock one is 48 mm and ours is 52 with the possibility of other sizes as well if the demand is there. Hope this helps a bit.

Randy
Team M7
www.m7tuning.com

 

So...I can't do this on the coffee table with my Dremel?

 

[QUOTE=maxmini]JLM Great explanation , you have been here before. The real difference we are seeing with the other TB's and ours is in two major areas. One the actual surface left after the enlarging process and the second is the fitment of the throttle plate itself and the all important shape of the edge. We go to great lengths making sure the surface is as smooth as possible and it is noticeable to the naked eye as well as touch.As for the shape of edges of the plate that was derived from several hours on the computer to come up with a shape that maintains its constant clearance even though the angle is changing. In the past many larger throttle bodies had a hard time idling properly and required a lot of re clocking of the internal gears. With our current throttle plate we are now able to just bolt it on and get a immediate idle to our specs within +/- 50 RPM. One more last area we feel we are doing as well as anyone and better than some is the way we re attach the cover after the modifications have been made. We are able to make the stock aluminum band work again which provides a superior fit to the other methods. A case in point is one of our new customers came by the last Steve's/ M7 install party and had a throttle body which had been installed by the dealer not 24 hrs before. Their method of re attaching the cover was with electrical tape The tape had come undone and needless to say the owner was slightly miffed as we were helping him get it back together so he could return to the dealer and give him a piece of his mind. I won't say who the other manufacturer was but it begins with D One last note I had given the size of the TB for the cooper as being much larger than it is. The stock one is 48 mm and ours is 52 with the possibility of other sizes as well if the demand is there. Hope this helps a bit.

Randy
Team M7
www.m7tuning.com[/QUOTE]

Randy and M7,
Thanks for the details. If the stock MC TB is 48mm is it true that the stock MCS TB is 57mm? What is the point of having different size TBs for the MCS like 61,62, or 63mm available unless they were for different set ups or offered at different prices due to performance differences.

It would make more sense to have one TB for the MC and one for the MCS. So for the 61,62, and 63mm TB what is the difference besides diameter rebored? Is all else the same or are there other technical differences?

Has M7 or anyone else done a dyno before and after with any of these TB? I'd like to see what difference it makes for the MC and for the MCS. Where if any is the modded TB giving more power or torque?- High RPMs mostly or throughout the powerband?

Can you comment on what difference it makes to have TB upgraded alone vs optimizing this mod with ECU upgrades or other mods such as intake, exhaust, reduced pulley, etc.

Thanks.