artguy

hey all...

I wanted to post a quick update in regards to the m2 setup Im running.

the car is finally running pretty strong. It still needs dyno tuning badly as the power fc I had purchased when I bought it from the rx7 store/xs engineering is definitely not tuned well for the mods I specified. it is currently running extremely rich...extremely stinky exhaust and burn my eyes rich...thus performance is not even where it should be. everything but the tuning is running well.

After solving some boost problems related to a sticky boost control actuator I gave her a few runs to see if the problem was finally worked out. Below is what I found.

boost comes on as advertised by m2 at an early 2800 rpms....thats full boost. For a few runs I pushed 15lbs and noticed that they pull much much harder than stock once the secondary turbo is online.

after 6500 rpms the gains from the streetport combined with the larger turbos are also considerable.

I also noticed that driving style is slightly different with this setup. The turbo wheels are to the size that it seems more important to pay attention to gear and rpm range when choosing to use the peak power that the car has. some of this is probably the tuning issue.

I can tell that launches are much better with the early spoolup time. however use with just the first turbo online without hitting transition seems to be a bit less responsive than stock (though this is probably just to blame on my larger streetporting and the resulting low end torque loss) the kick at transition is very nice....

in comparison to stock...the stock set needs 8 lbs for the secondary to kick in I believe. The m2s do not function well at low peak boost levels as the larger wheels need at least 12 lbs to get spoolup to happen efficiently. this is no problem for me...hehee....as I will run the most boost I can until I get my IC....which will be around 13-14lbs. once the IC is installed I will be running 13-14 for the streets and will run 17-18lbs for the once in a while playtime. (as long as my car is tuned well and the temps and fuel levels allow).

m2 claims that these garrett turbos were built for and can handle 20 lbs...which I have no plans to do....but in comparison to the 13-14 lbs of boost the stock set will handle without meltdown ......even less than that is a happy number to me. I ran 12.5 lbs on a stock set for six months and they melted and leaked....we shall see how well these do at my boost levels once a year or so passes.

I also wanted to say that m2 has been incredibly helpful in diagnosing my boost prob and helping to get my car running strong...they returned calls promptly and even called to see how things were going...they walked me thru the entire process and helped find the problem. both bret and brian showed a lot of patience and encouragement. believe me...it was appreciated.


however....the oil line restrictor pill is still not here and thus there is some smoke at startup...not a whole lot..and definitely less than my stock leaky junk I had previously...but smoke none the less.

I will post my dyno numbers once the tuning session happens when xs reopens shop. I tried all week to get in..but they were just too busy with their move.


j

Flybye

You know, one thing I think all of us certainly are waiting for is for a good dyno run of them on an FD comparing the stockers against the these running the same boost and nothing else other than a modified fuel map to handle the increase in flow.

Why hasn't M2 done this? You would think they have access to a before and after car and a dyno, no? SO many people question on either getting these or going single.

luneytune

Oil Line restrictor pill? What the "H" is that?

Flybye

M2 says that the stock oil system feeds them TOO much oil. Apprently, they need a restrictor in the oil line to the turbos to lower the pressure and allow them to spin as freely as they should.

artguy

Im not sure why m2 hasnt done it...I will say that they have been anxious to see my dyno numbers and have been very helpful in educating me in dyno preparation and caution....there are not many people running them...captn bill is the only other I know of..besides m2's race car.

the oil line restrictor pill is used because the ball bearing set need less oil than the shaft/sleeve bearing that the stock set has. too much oil means that some will blow on thru the turbos....the restictor pill will act as a mister and keep the oil levels to the proper specs. it is to be here any time.

j

luneytune

Interesting! Thanks.

Street King

So are the M2 ball bearing going to start replacing that single turbo conversion in my head? Iam looking for mid to low 11 sec passes.

artguy

I dunno....take my mod list and add a decent IC....and a good dyno tune and launch kit and gears....that will put you close to those on of numbers...if u r a good driver.....at 17-18lbs you should be somewhere around 375-400 hp at the wheels if it is tuned correctly.

I chose the m2 because I hate lag. I cant stand low end power loss and wanted to get as much of my low end back as I could since my ex streetport ran away with it a couple years ago.

honestly though..Im not that great of a drag driver...Id be happy with low low twelves.

j

pp13bnos

iTrader: (1)

I've talked to m2 about the upgrades, and here is what they just e-mailed me back.

Hello CJ,
The turbos are good(in their efficiency range) until 20 PSI, which with correct tuning and parts should yield over 400 RWHP fairly easily. The restrictor pill takes care of the oil leak problem. The turbos do require some modifications to make them work effectively, such as porting the inlets to match the new twice as large turbochargers. They spool very quickly hitting full boost by 2800RPM and not running out of steam as they hit
7500RPM. With your core we are looking at approx 3 weeks to turn these turbos around to you. I hope that answered your questions.

Brett Payne
M2.

pp13bnos

iTrader: (1)

On a side note, i was planning on going single turbo. But M2 has me realy considering going upgraded twins. I realy like the bottom end punch of the seq. system, and i know that a big single will pretty much kill that.

If someone can show me a dyno run with upgraded twins putting down 370-400rwhp twins (pettit, m2 or whoever!) I'd do it. Then i won't have to sell my m2 intake, efini y pipe, down pipe etc. It'll just be bolt on kinda thing.

So someone hurry up and get your car back to they dyno! I need some hard numbers! CJ

artguy

just wanted to say...what m2 told you is what I have found out first hand. those turbos dont quit pulling at high rpms..they keeeeeep on pulling...its hard to shift..haha

three weeks til dyno tuning...yum yum

j

racer rx

Anyone know how M2's stand against the new 99 spec turbos?

jc

kwikrx7

Jason, I just noticed your your mod list - still have the stock cat and ic!!! Get that thing breathing! I hope everything goes well with your M2 twins - sounds like you've had quite a few problems along the way but once you get it tuned they'll go away. Throw a hi-flo cat and medium ic on and you'll really get those turbos going. I don't think a front mount would benefit the M2 upgrades though. Looking foward to your dyno results.

RX7s

I have heard that the apex ball bearing turbo are also great for street use . Apex claim that their turbo spool up as quick as the stock twin with greater high end power. What do you guys think

RX7s

I have heard that the apex ball bearing turbo are also great for street use . Apex claim that their turbo spool up as quick as the stock twin with greater high end power. What do you guys think

Malachi151

Exactly. I've ridden in an Apexi RX6 car and I'm convinced its the way to go. So much simpler, so much more reliable, AND so much smoother. No transition, no surge, just one strong even pull. Plus this turbo DOES give you MORE low end power then the stock setup.

The guy I rode with was just tapping the gas at 3,000 RPM and the car was jumping forward hard.

I was very impressed, and the car I rode in wasn't tuned properly, was running stock IC at 14 psi, and really the only mods he had was full exhaust and the turbo kit and that was it. That was was very fast, had more low end then my stock setup, and more top end too, and under the hood it was so much cleaner and none of those damn hoses.

I hope to be running the RX6 in about a years time.

rotorbrain

anybody notice that artguy is running "3mm" ceramic seals. that is crazy. i dont have the ***** to use thoughs. . . its probably actually the money. hehe

pp13bnos

iTrader: (1)

Anouther factor as why i'm considerig it is because emmisions is going state wide next year in Oregon. I don't want to deal with paying off people, throwing back in a twin turbo setup, etc. Might as well go with the upgraded twins. Yeah, they won't look nearly as pretty, or simple. But a vacuum line job should take care of 99% of the boost problems anyways.

CJ

GoRacer

iTrader: (2)

Since it retains the smog pump and perhaps could get CARB approval. But a single changes the car, you can't say twin any more. Although it's not as rare as it used to be. Max Cooper has the Apexi and says: "it's not rebuildable". I'd like to have the M2 twins Non-Sequential myself.

tomaszjc7

-Anybody know??

-Tom

Malachi151

What do you mean by "it's not rebuildable"?

I agree that chaning the nature of the car from twin to single isn't something to do lightly in terms of being true to the character fo the car. That is the biggest reason why I may not go single.

I see no reason to get twin and go non-sequantial. You would have more lag then a single turbo setup. Non-sequantil is like the worst of both worlds as far as I can see. You still have a more complex system, and you also have the lag.

Can you run a midpipe for inspection w/o a smog pump and then take it back off after inspection?

artguy

I went m2 for the emissions reason. the rx6 was my first choice as it is similar in performance and lets you ditch that rats nest under the plenum.

kwik rx you are exactly right and you have great advice!....both are already on the list...Im going to put on the greddy IC until I can afford the m2 medium...I also will be running a midpipe after I get the sucker smogged. (for race use only..hahaha..good thing I race around town!).

I had the option of going non seq....however LAG SUCKS!!!!

if I was not running a streetport Id probably go non seq as they kick like a *****....just mixing both the streetport lag and the non seq is too much for me on the street.


Ill let you know how they compare to my stock set as soon as I can get in on the dyno.


j

maxcooper

Hey Malachi,

No one in the US is authorized by IHI to rebuild the RX6 turbo. That means no one can get parts, which means almost no one will even take a look at it. When I got mine, it had some small chunks missing from the turbine from a run-in with an apex seal. I called all over the place, and no one would even take a look at it... except for TEC who ended up trimming the turbine down to get rid of the damage (it was very minor -- diameter went from 62mm down to about 60mm). They rebalanced it and sent it back. It was $260 or something like that, which the previous owner of the kit took off the price for me. TEC is great, if I have any turbo issues in the future, I will be calling them.

I was long a sequential hold-out. I worried that I would lose the low end responsiveness of the car if I went single. However, I am single convert now. The RX6 does take slightly longer to spool up than the stock turbos at the very low end, but you are making much more power by the transition (4500 RPM). The single make the car feel effortless -- it just revs smooth and fast to redline. I still like the sequentials, and the emissions advantages are extremely compelling, but I love the way the car feels with the single.

I also have been pretty anti-non-sequential, but I have come around to the idea that it is good to get rid of the transition, and the non-seq folks have been saying that spool up isn't bad with the exhaust open. Of course, you do lose the "world's greatest active muffler system" (the sequential system) which makes the car a lot louder below 4500 RPM. I drove a non-seq car with two high-flow cats once and it was pretty decent, but it didn't make me want to convert my car. If I had two turbos, I think I would prefer to run them sequentially, but I understand why people go non-seq now, and it would be nice to get rid of the complexity.

I think you can run an air pump and stock main cat with the M2 upgrade twins, so they should be great for emissions testing. And it is quite common to swap stuff on and off specifically for the test. My last test required the reinstallation of my pre-cat to pass. I also had the stock air box and IC installed (no hose clamps or bolts, with cardboard and duct tape on the IC duct to cover the battery hole -- it was funny!). Good thing I kept that stuff around. I've got a set of turbos sitting around in case I need to "go stock" for my next test.

-Max

kwikrx7

I'm not quite understanding why people are so anti-nonsequential. Max, you drove a non-seq car with 2 hi-flo cats - your emissions out there must be strange - we don't have it yet in our area Like I said in other posts I have full boost by 3200 rpms (stock turbos) running non-seq. A hi-flo cat will provide more low-end with non-seq than a midpipe. Between 3200 rpms and 4500-4800 rpms (transition in seq. car) both of my turbos are going full blast where in a sequential car they both aren't online until between 4500-4800 rpms - very big midrange power advantage for me. The idea of having "2" or twin turbos is to have faster spooling than a larger single. The average single turbo won't spool until atleast 3500 rpms (yeah, the RX6 a little sooner I think) but most around 4-5K rpms they'll make full boost. But upgraded twins running parallel should see full boost by around 3500 rpms with the right setup. I don't think there is anybody on the board running upgraded twins parallel - I plan on doing it this summer and hope to get some good dyno results.

Malachi151

Max, do you autocross your car? After riding in the RX6 car, I loved them, but I am still leary of autocrossing a single turbo RX-7.

So you are saying that there IS aplace that will service the turbos then right?

The car does feel totally different when single turbo, which is a good and bad thing. It actually does feel "better", but it doesn't feel like and RX-7 anymore, which worries me.