Ok well here is the deal I just got a 1990 Turbo Miata with the Greddy kit. I know nothing about miata's. All I have owned was VW's the miata is gonna be my new track/auto x'er. I have alot of ? but for right now i am gonna ask my main one. Why the hell does this car have such a bad turbo lag problem. It doesnt hit full boost(10 PSI) unit 4400rpm.......Is this normal or what. From what I here it is either running lean or needs a new down pipe and bigger exhaust. Please help......

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that's about normal....see "dyno day pics" for two higher HP greddy systems.

but if you are on the stock DP, then you will benefit greatly from opening it up

 

how can I tell if it is stock and were can I get a new one from?

 

I think the stock one is pretty skinny like the stock Miata exhaust. Not sure what to look for to make sure, but the aftermarket ones are 2.5in.. Mine is from Racing Mazda, I think someone on this forum makes them too.

http://www.racingmazda.com/miata-exhaust.htm

 

Are you in Florida Lou?

 

Yeah I talked to you today.....I am just doing some research on what you told me.

Who is the person that makes them?

 

Def. do bigger downpipe and better intake tube. Noticed you're still running the stock one.

If you think it's running lean get a WB02 and check it out, that AFPR is adjustable.

 

i dig the wheels. looks good!

 

Turbo tony makes a very quality product. He was the guy that was making the racing mazda ones, but now makes them on his own time. I will try and dig up his email address for you. There is also the new begi unit, you can get one of those and end up with a very high quality product. Just make your choice and go for it, but you need to get rid of the stock dp in order to get any real kind of spool out of that turbo.

 

yeah that would be great....If it is not that hard to make I have a friend who is a good welder, I am sure he could make one for me. Also is 10 PSI safe on this motor?

Now what should my numbers be on the wideband?

 

yeah, 10psi is nothing, this engine is fairly bulletproof given a good tune.

you'll want to shoot for around 13-12:1, most people run 7-8-9* timing in boost, just listen for ping, that's the engine killer


get us a shot of the DP and we can tell oyu if it's stock or not.

also, is the "lag" you are speaking of, just between the transistion of vacuum and boost?

what other components for fuel does it have? 1.8L injectors, stock pump, and FMU is getting pushed to the limits at around 170rwhp (around 8-9psi)

 

DP looks stock, it's tiny and black in the engine bay pic. Easy way you can tell yourself is if where the pipe meets the flange, if there is no bellmouth it's stock.

I second Brain's comment, 10 psi is absolutely safe. FYI the Miata's engine was originally a turbo engine in the 323 GTX, so internally it's ok for turbo.

 

Nice looking car.

Is the catback stock as well?

 

yeah pretty much now that i think of it the pipe coming out the back is only 2inches.....what is a good size to go with? 2.5 of 3.0 for the down pipe and the full exhaust?

 

Most go with 2.5" the whole way. No one makes a 3" dp for the greddy.

 

ok well now i know what i need to do..

Heat sheild around the turbo(there is nothing and it is melting my master cylinder res.)

get bigger exhaust.

 

Begi just starting selling a downpipe for the greddy didn't they?

+1 for heatshield.

Not a fan of red...but damn that looks good.

 

Nice looking set up. You should plan on replacing those silicone couplings off of the turbo as they're the supplied Greddy ones and aren't worth a ****.

 

yeah I know those are on my list but not #1 on it.

 

just curious, how much did you pick it up for?