JRSC Boost Upgrade Kit
 

A friend of mine locally just purchased this kit for his 1999 Miata with a basic M45 setup. However he has a concern and I'm hoping that maybe someone here has some experience with this.

In the instructions for the kit it says: "Requires use of the original fuel pump. Some early 99-00 Miata Supercharger kits supplied a larger pump."

His concern is that he has a Walbro fuel pump, but not one that he got with the supercharger. Does he need to go back to the OEM pump or is he ok as is? Does anyone know why they would specify using the OEM fuel pump?

Thanks.

That is a very strange. I can not imagine why it would matter. What if you wanted to put on nitrous or bump up boost.

Could it have something to do with fuel preasure? I hate to speculate, but maybe an adjustable fuel preasure regulator would be needed.

I'd use the walbro. You'll get more gas and better pump.

Your good, just install the pulleys and what not. :)

If I'm not mistaken isn't the jackson racing afpr the same as the Begi unit? It should be adjustable, If you get too much gas in boost.

Should be fine, a lot of that text is copied from the original instructs. The newer, Big Boost Kits come with the PowerCard *Pro* now, correct? The old PowerCard (non-adjustable black box) used to dump a boatload of fuel and go super rich to account for every condition, so using a stock fuel pump was recommended. The PC Pro, being adjustable, should help mitigate that condition.

I can´t understand one thing.
The Walbro do not increase the Fuel pressure, it just give more fuel wealth when it needs.
The OEM pressure regulator says the pressure, not the fuel pump.

With a external afpr you can achieve higer pressures.The stock will only supply so much. It also depends what size and pressure rating aftermaket pump you buy. 190... 255 etc.

Some pumps do increase fuel preasure. When preasure is increased at the pump, the preasure regulator will not keep it to the level it is set at. That is why some applications need an adjustable preasure regulator.

If the Walbro does not increase preasure, but simply supplies more volume, than there is no need to worry about it.

So do you have powercard or afpr and a timing device?

The kit came with the PowerCard Pro and Timing Controller. I don't know if he has an AFPR on his car or not.

Either way, the Big Boost Kit puts him in that gray area of almost needing an IC or pulling timing. Even at 8 psi or just under, the adjustability (even for a basic piggyback) he's in need of a Wideband now. If he can't figure that out yet, he'll definitely know once the readings are in.

I just ran by the MiataTurbo Wiki page, and it mentioned that 99 fuel pumps can suffer from a lean spot at the top of the RPM, so he may want to keep the Walbro anyway.

Miata Turbo FAQ: Fuel Pump

Mmmmm. This is where is where I jump off the boat. When we where buying a upgrade kit it came with a afpr to replace the powercard.:dunno:

The guy selling it claimed the pcpro wouldn't work for 9psi. He probably didn't know what he was doing.:dunno:

But we already had a bandaid setup. I already knew the bandaid setup, so i wasn't hard to persuaid. lol

And with all the pcpro hate around here. I just went and bought some pulleys.

They may have better pcpro's now. But then again I know nothing about them.

I would call jackson racing in the morning.:makeout:

If you can sift through the morons......They pissed me off.

You know, screw Jackson Racing call trackdog. But watch for him too. He points you in the direction he sells! LOL. He does have a buisness to run, and does have good products.

He will shoot you straight if you ask exactly what you want in a question.

He has helped with advice several times. And gave me some good deals on some parts. give Gary a call hes a good guy.

Tell him todd with the yellow miatas sent you. We both have a thing for them.
Welcome To Track Dog Racing

Thanks. I will make a call tomorrow. I've talked to Gary a couple of times, he's always helpful.

Isn't he sticking with the MS? If he is, all he needs to up is the injectors and he'll be fine.

He doesn't have an MS, although I think I know who you're thinking about. This is for Lee's dad.
I still wasn't able to call TDR, damn work.