ChairFaceChippendale

iTrader: (1)

please do. that's around what i'd like to get out of a supercharged car.

Agent

iTrader: (2)

I can't find my gtech right now, but before I switch pulleys out I want to get an approximate 1/4 and horsepower rating with the current set up. In the next month it should be pretty much the same + intercooler and new clutch. (currently at 5psi) I really think that with the right tune I could hit 165 at the wheels. With my bigger pulley, and the intercooler, I would like to be at 200. Some tuning, maybe a few random things (perhaps a bigger pulley maybe) and I should be able to hit my goal pretty easily. The thing I have really enjoyed about the super charger is the bigger engine feeling that it gives you. My MP62 puts torque out at every rpm level. It does not matter which rpm I am at, I still have 5+ psi when I step on the gas. It's really wonderful. I'll keep you posted. If you are curious and I haven't been on in a while, just bump me with at PM.

mhoward1

Kevin B (I can't remember his nick on here) has a setup very similar to yours with 212 ish at the wheels. You may want to talk to him.

Agent

iTrader: (2)

212 with my current set up? Or the set up I'm going for?

mhoward1

The setup your going for. He has worked out a lot of the kinks.

Agent

iTrader: (2)

Did he fix the a/c issue?

eunos1800

I'd go for exactly the same kit (MP62 hotside 125/65, TDR copy IC, WI).

If i did it again i wouldn't bother with the EMU though i'd go for the Adaptronic instead.
I'd also not bother with smaller crank pulleys, 125/65 is minimum i'd go for.

I'm chuffed to bollox with my SC, 3 years on and it's been great.
Had a couple of problems with the crank pulley bolts snapping but both were my fault.


Cheers
Mark

mhoward1

Yes, but I have no idea how.

Agent

iTrader: (2)

please ask. i'm in an epic fail right now.

92mazdarati

So I just finished my Jackson Racing Supercharger installation last night on my 92 Brilliant black special edition. I decided to go supercharger because I wanted to do something different. I have had three turbo miatas, my last one being a 10 psi greddy setup that I was very pleased with. To be honest I was under the impression that a supercharger would be less invasive and would require less molestation under the hood. After installing the setup I would say that the supercharger actually involves more disruption of under the hood systems than a turbo install does. As for power, I was disappointed. I thought that the supercharger would be better having a more broad power band, but actually find myself really missing the sling shot feeling you get when the the turbo hits full boost. I haven't installed my boost gauge yet, so don't know how much boost I am running, but the setup I have is just the basic jackson racing kit. I bought it used on ebay for $1265 shipped(about the same price as a new greddy kit). After having this setup I would definately advise anyone to go turbo over supercharger. The turbo is much easier and cheaper to modify. In order to get more power out of my supercharger kit I have to get a big boost kit. Unless anyone knows where I can source a pulley that would be the same size as the one that comes in the big boost kit, I believe it is a 62.5mm. Otherwise I will just wait to find a used big boost kit. I already have the larger fuel pump, larger injectors and tuneable fuel management. It is also much easier to find a intercooler kit for the turbo kit. I still do not regret doing the supercharger. I consider it a learning experience and enjoyed the installation as I am sure I will enjoy figuring out ways to modify the system. I should not that I also have the goodwin racing roadster sport exhaust on the car and a ETD racing polished stainless header which I installed before doing the supercharger. I felt that the header gave a good increase in power and was $100 well spent. I also put on a cheap($65) polished stainiless radiator air diversion panel, which I would say looks nice, but fitment was poor. So overall my opinion on the supercharger is this: At $2400, its not even close to being worth it. At $1200 I'd probably still order a new greddy kit instead.

oreo

when I decided to go the sc route, I knew I would be sacrificing power compared to a turbo system with the same level of work and $.

I was hoping I could achieve the same level of power most turbos attain, and still get the instant on power that is an advantage for the tighter autocross courses that are run up here in Canada.

I'm not there yet, but am still happy with my choice.

Agent

iTrader: (2)

So you're running 5psi on a small blower and you are complaining about it not being as fast as your turbos? I mean, if you just finished the install do you think you are being a little bit hard on your choice? You complain about the "slingshot" feeling or rather the lack there of with a supercharger. I guess I understand what you are saying, but there is no slingshot feeling on a motorcycle, and that does a 1/4 mile in about 10 seconds. I guess its slow though to the mighty turbo that you have, but weren't happy with, because you wanted to get a supercharger. I guess to each their own. I would rather GO fast than just FEEL like I'm going faster. I can be cruising on the highway at 80mph now in 5th gear, tap the gas and watch the boost gauge instantly hit 6psi, and hit 100mph in just a couple of seconds. And thats just with a small *** pulley. Thats not even with the set up that I'm going for! My car with a small 5psi pulley feels like my bmw does with 160 at the wheels. It doesn't feel like anything crazy is going on, it simply feels like a much large motor in my car now.

I don't want to sound holier than thou, but it doesn't seem like it is that difficult to get a supercharger to put out close to a turbo's output... SOT has a 150mm pulley, and that combined with the 62.5mm crank pulley should be well over 14psi on the average set up. If you have that on the mp62 it would most likely be in the neighborhood of 240rwhp. Maybe more if the car could handle it. I really don't see any cars reliably putting out anymore than 240rwhp, so if it's going to be turbo or supercharged, whats the difference? Straight line goes to the turbo, and for something tighter like an autocross track, the supercharger has the advantage. Am I missing something?

rrroadster

That would be me. Hi guys, Kevin B here. I'm more of a lurker kind of guy. Marty emailed me this link.

I'm running a MP62 Hotside I got a couple of years ago from BRP. It's installed in a '93 Miata with 1.8 engine, harness, ECU and brakes. It's got an '86-88 NA RX-7 LSD with a 3.9 ring and pinion.

A 37mm Koyo radiator provides water cooling with a custom remote oil filter and oil cooler installation. To get adequate air to heat exchangers, I've cut a couple of 2.5 X 8 inch or so holes in the front bumper, above the plastic impact absorber. I've also vented the hood significantly.

The stock injectors are controlled by the ELF piggy back that came with the BRP kit. I'm pulling timing with a Bipes unit to avoid knock.

It's intercooled with an AAIC system based on the BRP NB kit. The guy that designed/supplied it to BRP doesn't live too far from me. He felt sorry for me when I started asking around for NA solutions and helped me tweak it for a NA Miata. You've got to have the intercooler to make higher power levels. I think I was 160-170 RWHP pre AAIC. Keith Tanner suggested to me a few weeks ago to ditch the intercooler and go water injection. I'll have to sit on the fence for that one a while.

When I dyno'd the car last spring, it was with a 60mm nose pulley and 100mm crank pulley. It made 201 RWHP with about 175 ft-lbs of torque. The cool thing was that the torque was there through the whole RPM range. It jumped right up to 175 at the beginning and flat lined across. At the dyno, the guy running it said my injectors were starting to lean out at the end of the pull, so I added a 550cc 5th injector with a Split Second controller. It now runs a bit rich, but I'm willing to accept that over knocking the motor apart.

I recently spun the crank bolt out while on track, which buggered up the crank. I now have a donor motor for a high HP build. The goal is for 300+RWHP. I will get rid of piggy backs for a replacement ECU - either MegaSquirt or an AEM unit recommended by a friend.

Last year, I had temperature issues on +90 deg days. I never popped the head gasket, but had to drive by the T-stat temps.
With the replacement motor I just installed, I did a coolant reroute. I got most of the inspiration/ideas from this site. We'll find out next week how well it works with 3 days at Carolina Motorsports Park. If that track doesn't kill your car, then it's pretty tough.

Agent, to answer your AC question - I'm not sure I can help you much. My car is an SM2 prepared track dog. In preparing it, I did an AC & PS delete. You won't be able to run AC with my set up, it's too tight. If you get a Track Dog Racing AAIC, you'll be able to keep the AC, but it will require a significant reduction in the strength of your core support - you have to cut it. I personally found that to be objectionable. I recently read where Flyin Miata is going to/has upgraded their AAIC to be compatible with the Supercharger kit they now sell - which is the old BRP kit. I'd bet they make sure AC can be retained.

I like the SC application for the track due to its simplicity. Blower + belt = Power! The trick is picking the right components: MP62 blower, 6 rib belts for starters. The power's always there, but comes on without a sudden overload - great for digging out of corners at the track - doesn't suddenly unsettle the car's balance. Recently, I've bumped the crank pulley up to a 110mm. Not sure what boost this resulted in - too busy too look. I can really feel the difference digging out of T1 at VIR. I have to worry about the speed making my exit radius too large and running off at exit. Uh Marty - I knocked another second off my VIR Full time over Mem Day(down to 2:20's).

A friend of mine with a stock C5 Corvette could never pass me until he hit 4th gear. I've never driven a turbo car and this one is my first FI. The only turbo cars I've driven around have been 944's and RX-7's. Most 944's try to drag me on straight aways. After the first try, they pull over next time I get behind them. The other week I was running with a Turbo'd 2nd Gen RX-7(Daniel Clark's Scud Mobile). He was a little quicker than me on the back straight. He says he has to time when he gives the car gas in anticipation to when the car actually delivers. With my SC'd car, it's there for the asking.

Oh yeah, did I mention the car is an absolute blast to drive?

KB - aka rrroadster

Agent

iTrader: (2)

Kevin, thanks for the response. I have the same kit that you have. Did the 60mm crank pulley come with your kit or did you purchase that one separate? My goal is to be just under 215 at the rear wheels. Do you think thats a pretty safe power rating to be at? Take it easy.

rrroadster

I acquired the 60mm pulley in the classifieds. The BRP kit came with a 65/95 combo. Anything smaller than a 60mm nose pulley and you'll start experiencing belt slip.

With a 60/100 combo and the right tuning you should be able to make 200RWHP like I did. I may be able to dyno my 60/110 combo this weekend. A 126/65 ratio is 1.938, 110/60 is 1.833 so I'm wondering how close to 225 I am. By setting up a ratio between last years numbers (200/1.666) and my current pulley ratio of 1.833, I get 220. We'll see.

From what I've always been told/read, 235 is the ceiling for a stock engine. I'd be real confident in 225 RWHP with the approriate cooling, both engine air and coolant.

My goal for next year is to get a built motor in the car and work up to 300+RWHP. I want to pull Corvettes!

Oh yeah, when you hit the new speeds available to you, be prepared to pony up for brakes! I need to bad. Braking down hard from 126-129 mph can get real dicey. There have been a couple of occasions where all I cared about was keeping it straight and on the tarmac...and I'm on 1.8L brakes. Once I started braking on track left and ended up track right before the turn. I was just along for the ride on that one. Backing up the braking zone solved the dancing, but I know it's costing me in lap times. I'm going to try some brake ducting for next weekend, but I think it'll end up being just a band aid.

KB

socal pat

My 2 cents. If you are going for more than 225 hp then get a turbo and be done with it. If you are sure that you will be happy with 200-225 then a SC is a real contender. I'm at 12psi (went down 1lb when I put in 9:1 pistons) and around 205-210 whp. Unlike the hotside guys I'm not running an intercooler, but have a 440 cc/min 5th injector and a timing card. IMO putting a cheapo m45 kit and then expecting to put the money in on the backside for Engine management, cooling etc. and hoping to get anything near an MP62 is climbing a steeeep slope. You might get there, but you'll be too worn out to enjoy the view. You will have a finicky, high strung system.

I walked a Mustang GT this morning on the way to work. I could not walk a Vette. Oh well. I knew this going in so I'm happy in my niche.

eunos1800

Your talking purely about M45's right?

Mp62's will happily put out 240bhp all day every day (mine should be between 220-240bhp).

You can get more out of a MP62 300rwhp has been done a few times, but then SC reliability starts to become a problem.

The thing i can't understand is why most SC users don't use better fuel/ignition management, theres very few SC owners running a full standalone.

steelrat

A hotside will let you run more boost, with the IC.... safely. I've been in a 240 hp SC'd car, and it was wicked.... Been in a high turbo car too.... both good, just different.

If your goals are 200+ personally, I don't think a CS is necessarily the best way to start, only because of the lack of "easy" cooling. That said, I've driven a CS, and for low boost, it's lovely. But higher, deal with the throttle volume for the hotside.

Dave,

eunos1800

I can't see any point in a coldside at all.

socal pat

Yup, I was talking about M45's. I am also running 240bhp (210whp) no issues. Not many people are getting much more than that. The guy from Colorodo who has 250hp in his signature is actually running around 210 at sea level. Father Leadfoot is running some nice numbers on his twinscrew, but I guarantee it is not as trouble free or smooth driving as a 200-210 WHP (240bhp) car. There are exceptions to every rule, but they are just that...exceptions.