Drewkeen

iTrader: (2)

I bought a 1992 Miata with a Greddy turbo kit and <5k miles on a rebuilt 1.6L engine. I know that it would probably be fine for autocrossing, but how would it fare on a road course since it is a hot air setup and on stock injectors? It has a Walbro 190lph in the tank. Is it a bad idea to run this on a road course or is it fine to run a hot air car at 5psi for extended periods until I decide that I need more power (and have the money) and go with an intercooler, injectors, engine mgmt and some kind of air meter. The car also has no cat and a full 2.5" exhaust and suspension mods.

turbobluemiata

iTrader: (8)

With a quality synthetic oil and your cooling issues under control (no overheating) I don't see why not? do you have a wideband?

Drewkeen

iTrader: (2)

The car will be ran with Mobil 1 (unless someone has a better suggestion on brand and weight...maybe time for a search)

I always keep a close eye on coolant temps. I didn't know how hot the IATs would go under load for extended periods and lead to knock.

I do not have a wideband in the car now, but I will most likely put one in it. It is almost silly not to have one as cheap as they have become.

turbobluemiata

iTrader: (8)

I ran my greddy unintercooled for a few months with no knock just had the timing set back a little bit, and I run amsoil oil btw. And since you have an NA you can use your oil pressure gauge as knock detector if it starts shaking under boost then its knocking.

mx5dude69

regarding that "knocking detection method", that's only true for the earlier pressure sensors, or does it still apply to the post 94, that only have On/Off positions?

turbobluemiata

iTrader: (8)

he has a 92 though yea your correct though

Drewkeen

iTrader: (2)

Good to know about the oil pressure gauge, did you road race/auto-x with your car when it was not intercooled?

Also, I tried to send you a PM but I am new so it won't let me. I wanted to see your setup and don't have a myspace.

gompers

iTrader: (4)

Do you even feel the boost at 5psi? ;p

BenR

iTrader: (2)

Personally I wouldn't push it very hard on a road course without an intercooler and an oil cooler. Retarding the timing will help, but at the same time it will create alot of underhood heat, resulting in melted brake master cylinders.

Drewkeen

iTrader: (2)

Hah, very funny. Drive a stock miata and hop in a boosted one and you can feel a difference. I am used to to Mitsu motors that run more than 5psi stock. I didn't get the Miata to be an all out drag car or to make huge power...I wanted something that handled like it was on rails but it is hard to have fun in something slower than a civic.

Drewkeen

iTrader: (2)

How would an intercooler and oil cooler help save the master cylinder? I would figure than an intercooler = most boost = more heat on the turbine side = melted master cylinders. It has the little heat shield on it, should I also wrap some heat tape around the master cylinder and the hoses behind the shroud for extra heat protection?

I will do a search on oil coolers to see who has done what and when they are a good idea.

Does 6 deg. of base timing sound right?

Newbsauce

iTrader: (2)

I think he was making two separate points. 1> he would not track it w/o oil cooler + intercooler.
2> The underhood temps will be great for bbqing.

Run race fluids, heat shield your engine bay, and possibly consider the NACA duct that many of us are using to get some air into that hood.

BenR

iTrader: (2)

Newbsauce understood me.

Running hard on a track with a turbo miata requires some additional cooling, especially if your turbo is oil cooled. You can definately drive it around the track, but I pushing it with out some kind of oil cooling is not a good idea.


The intercooler will allow you to run more reasonable timing advance. Retarded timing causes retardedly high EGTs which melt your master.

6 is probably the farthest you can advance it with no charge cooling or race gas.

The heat created from retarded ignition is much hotter than the heat from alittle more boost.

miatamania

iTrader: (9)

Just custom make an intercooler setup for like 200 bucks...

I think the added safety is worth it.

Drewkeen

iTrader: (2)

It sounds like an intercooler is the next logical step, but the downside seems to be that when I do that I will also need larger injectors and some type of fuel control device.

Anyone want to link me to their homemade intercooler setup that allowed them to keep AC and PC?

BenR

iTrader: (2)

Why would you need more fuel just because you add an intercooler?

Drewkeen

iTrader: (2)

Because naturally I will be unable to resist adding more boost.

hustler

iTrader: (6)

oil cooler is a must.

Drewkeen

iTrader: (2)

I plan on getting an oil cooler for sure, I kind of just assumed that it would have one stock.

mike_671

iTrader: (4)

I have an intercooler at 5psi. Just did so i can advance timing a little bit. Since you have some money, do the oil cooler (fo sho), intercooler, godspeed radiator (or koyo), and If you got more money then move on down to water injection.

Im scared to track race (we don't have a track here anyways), i just cant see my self boosting for longer then like 5 minutes.