Buying a 99 W/BRP MP62 SC Non-IC 8lb boost, any warning signs?
 

Hi guys, I am thinking of getting into the Miata scene after many years of wanting to. Have my eyes on a 99 Miata 1.8L with a BRP MP62 Supercharger running approx. 8lb of boost and 93 octane based on what the owner has said. Non intercooled, stock internals, stock injectors. Has several mods such as CAI, full catless headers, stock cat, full exhaust, etc. ECU management done via a Jackson Racing Supercard.

I test drove the vehicle and it seems to run well. I did not hear any pinging or anything of that nature, and the power it makes is fantastic. However based on my limited research it is my understanding that this SC only comes with a kit that provides either 6lb or 10lb of boost and that the stock injectors can only handle around 6lb. I also test drove an 01 with a Kenne Bell SC running 6lb of boost and the 99 felt MUCH faster, the difference between the two was night and day. While I don't know these cars well enough to say for certain, I was thinking that it probably is running the claimed 8psi or more based on the vast power difference between the two, although again I could be completely off base with my limited knowledge.

Should there be any cause for concern? I am wondering if this would be a safe buy and if there is any reason to believe that this setup is improper and could potentially be running lean or have been abused in some way. The supercharger has supposedly only been on the car for approximately 5k miles. I am just a bit worried that it is being ran with too much boost on stock injectors and no intercooler and if I should be worried or not...

Any signs I should be looking for? Is this sort of setup and amount of boost safe to run on stock injectors with no intercooler present? I am intoxicated by the amount of power the car has, but I don't want my first Miata to turn out to be a lemon or one that was given more boost than it should for an extended period of time. I want to make sure that the way it is currently set up is safe and reliable and that there isn't any potential of damage being done. Thanks for the help in advance!



P.S. - I also noticed a significant amount of rust on the suspension components such as the control arms and accompanying hardware. The chassis itself seems to be rust free though. Wondering if this is also something to be wary of. It is pretty darn low too, has some pretty agressive lowering springs on it along with KYB AGX shocks. He says that he just recently bought the car and does not know what brand springs are on it, says that all of the mods were done before he bought it. He claims to be an autocrosser but says he never autocrossed this one due to it not having an LSD or welded diff. Any help is greatly appreciated

Lack of an IC + powercards are enough warning signs... But, it’s at the limit of what the powercards can do realistically.

On a ‘99 that’s been in a rust belt climate for it’s life I’d want to look really hard at the frame rail area located in front of the front wheel well liners. The rust starts inside the rails and you won’t know it until the bubbling starts which is already too late. You didn’t mention location.

So is that in fact too much boost to be running without an IC then? The guy hasn't had the car long but based on his comments I am assuming he drives it hard, which is indeed a bit worrisome. I did not notice any engine troubles at all aside for the idle dipping a bit low when at stoplights... the vehicle stalled out on one occasion because of it. Not sure what that means, any idea?

The vehicle is located in MD, although he claims it has been garage kept through most of its life. We do have some pretty bad winters here though, so that is definitely something I will look for. The top has a couple rips in it that are patched up with gorilla tape, so that's going to be another added expense when buying it. I will likely just get a hard top and remove the soft top completely.

So you mean the area right in front of the front tires, like behind the front bumper? I plan to go see it once more and get it up on jacks this time, so i'll definitely be sure to take a close look underneath.

Please let me know what you think though as far as the SC setup and engine goes, I'd like to know how big of a risk I may be taking buying it, if any. The guy claims that with this SC it can be ran at 8lb without an IC without issue. Either way, if I were to get it the first thing I would do is put an intercooler on it. I am still very interested in getting it and would treat it right if I do, just want to be sure that i'm not getting one with existing engine issues.

It already looks as if there will be quite a few things that will need to be done such as the top, intercooler, passing inspection with the full header & 2nd O2 not being hooked up, and who knows what else. I also noticed a very minor shimmy when driving at speed, could just need the tires rebalanced or could be a worn suspension part such as a shock mount, hard to say. I dont necessarily mind these things if the engine is ok, as it was an absolute blast to drive and is the fastest car I have ever driven, so it is damn tempting...

I'd specifically like to know if 8lb was an option out of the box for the MP62 as I have a feeling that it may be running ar 10lb of boost instead of 8, but that's admittedly just a hunch. It is my understanding that it should only be able to do either 6lb or 10lb out of the box with the included hardware. Based on what i've been told there has not been additional pullies or anything added. Is there any reason to believe that it may be running at 10lb vs 8?

My apologies for the long winded response, hope i'm not rambling on too much. It's just a big purchase for me and I want to be sure I make the right decision.

I originally had the BRP kit you have in my 2000 for a couple years, with the exact same powercard. I added the TDR intercooler. The stalling symptoms are well known and get worse after adding an IC. You can fix some of it with a 2nd throttle body + MS ecu + remote IACV + some tuning. Well known issues that some of us fixed by selling the MP62 and going turbo.

Re, the rust... The parts of the "frame" forward of the front subframe that you can't see unless you remove the wheel well liners. I guess technically it's part of the "Core Support". From experience, if I saw this I'd walk away from the car. You'll spend $2K+ to fix unless you're a great welder/fabricator.


https://cimg0.ibsrv.net/gimg/www.mia...82726ad2c6.jpg

Ah ok, thanks for that. I can live with the stalling I'm sure. Small sacrifice for nice power. I will definitely check behind the wheel liners. I still need to know if the 8lb of boost is too high for this setup tho without an intercooler and if there is any danger to the motor with that type of setup.

I got some extra undercarriage pics from the seller by the way, here they are. Looks like one of the rear control arms is badly rusted and likely needs replaced. That very well could be the source of that shimmy I felt. The rest looks like surface rust to me, but I am no expert. Let me know what you guys think of these.

And here's two more...

haaaaard pass. unless you are getting it for free.

Lol why's that?

Because its a giant tub of rusty junk with an old supercharger setup on band aids that no one here would pay any decent amount of money for. Unless they were crazy

You would sacrifice a lot for no reason whatsoever. You have much learning to do. Car is junk

Wow is that a rusty heap.

You are probably right... I have just started researching these in detail. Thanks for the heads up, I will likely not buy this. I could replace rusty suspension parts, but it's my understanding that as long as the frame and chassis isn't rusted then it's ok. Is that not the case?

But the most helpful and ass saving heads up of all came from the other Miata forum where someone actually informed me that 8psi on supercards without an IC is only safe when running both supercards that adjust both fuel and engine timing, something this car doesn't have. This one only has the fuel card, so thank godd for the heads up on that one, I will definitely not be getting it due to that.

You're probably right though, I am sure I have a lot to learn, but that's why I am here. I think the main point of these forums is to help each other learn about these cars. If I have a lot to learn then please school me if you don't mind. If there are any specific points you could point out for me that would help i'd appreciate it. Don't just hate on me because I am a noob, we were all noobs at one point. It sometimes takes a helping hand to learn.

I'd maybe pay $1500 for it.

... looks like i'm getting trolled. Thanks for the help.

I also legitimately would not pay more than 1500 for that car. probably not even that

Sure, they're way more smart about superchargers... BTW, the guy who told you all that is likely on a 1.6 using 1.8 injectors. Likely a MP45 not the same thing.

BTW, to answer the question you posed over there...

NA = 1st gen
NB = 2nd gen
NB1 = 2nd gen, 1st iteration
NB2 = 2nd gen, 2nd iteration


Troll...

Thanks for the heads up. From what I've been told, the previous owner from before had a boost gauge on it that was reading between 8 to 10psi, so it may actually be running as much as 10psi. He also says that it only has the one supercard that adjusts the fuel mixture and that the timing has not been adjusted. Does anyone know whether or not it's safe to run 10psi with that current setup without the intercooler?

but yeah, I think it is safe to assume that the car is worth more than 1500... some suspension component rust isn't going to devalue it that much. The SC alone is worth more than that. Lets come back down to planet earth here.

I promise you we're not trolling.

That setup under the best of conditions doesn't satisfy our requirements to call it "Safe" in the first place. It satisfies Miata.net, and i'm glad that they're telling you the answers to your questions that you want to hear, but it doesn't satisfy ours, and just because you're not getting the answers that you want to hear, here, doesn't mean that we're trolling. I mean really... 10psi on a hotside MP62 on stock injectors with nothing "controlling" timing in any way, non-intercooled?

You're already defending and telling us that our input on a car that you don't own, but are considering buying, is incorrect. Sounds like you've made up your mind. I hope the car treats you well. :)

I think it's worth $1500 because i think i could maybe make $1000-$1500 after spending a lot of time and effort parting it out.

WAIT!!

Is he saying that we're trolling him?

I thought he meant the seller was trolling him.

Power cards are worthless. The car does not have a wide-band oxygen sensor so you don't know what air fuel ratio it's actually running. There is no timing control so detonation is eminent. There is no intercooler so detonation is imminent. It's a Supercharger so it makes a lot more heat at lower boost than a Turbocharger would because it's far less efficient so there's detonation. It's running the stock ECU and needs to have $1,000 put into a standalone ECU so that devalues the car significantly. Anybody who's built a setup like that has not got any regard for proper engineering of a boosted setup and as you have noted he was beating on the car pretty hard so it's certainly not in good shape therefore another demerit. Agx shocks are some of the worst shocks you can put on a Miata for either performance or daily driving so that's something else that's got to be fixed. You need to buy real injectors so that's something else that needs to have money spent on it. Another demerit.

You say the car is fast. I understand that it may be fast to you but the car is actually not very fast. The car is probably only putting down around 170-180 wheel horsepower. Did you say you are in Northern Virginia? We have members in that area that you could meet up with and ride in a properly sorted out car that actually makes decent power.

We aren't going to the effort to tell you all of these things about your purchase because we don't want you to have a good time. We're telling you these things because we honestly believe them and have seen how badly things can go for people over the last 10 or 15 years. We are not new to this platform and we can help you if you let us. There is a better way. Come with me if you want to live.

You asked in your title of this thread if there are any warning signs. The answer is yes. Yes, there are several. And they are not trivial.