I am not going to go too in-depth on this kit. Just wanted to post this because I do see some incorrect facts about this kit, compared to others on the market. Also, to just share my general results with it.

I decided to go with this kit instead of the OTTPerformance Return System, simply due to price. Not knocking the OTTP kit, it is an awesome, good looking, and well made kit that functions flawlessly. But I modify a Cobalt, GM Eco Box, for a reason. I don't want to spend unnecessary extra money for the same end result.

ZZP does give you everything you need to install the kit. They even sent me the EVAP fittings that I did not pay for Some things I didn't like:

They included steel vacuum line to go under car from front to rear. It isn't barbed on either end, and in my case it was kinked and did not allow clear passage of air. I used about 15ft of rubber/silicone vac line and ran my own.

The regulator itself isn't barbed either, but few zip ties and I wouldn't worry about it. But the adjustment torx T10 bit on top of the regulator gave me tons of trouble. Stripped after just a few turns. Also, you need a Torx Security bit to adjust this. You could possibly remove the pin in the middle and use a regular torx, but I just used a security torx bit.

I installed using their Option B method, removing the stock regulator so I could have full control using the ZZP regulator. When doing this, the ZZP BRFS gives the same results as a full return style.

As ZZP advertises, there is no benefit to using a full return style as opposed to the BRFS kit. Only difference is, the regulator is under the car in the rear. So setting fuel pressure does require you to crawl under the car.

Zoomer says hes tested this kit to 70PSI of base pressure. I have personally tested this kit to 80PSI of base fuel pressure. It took it with 0 problems. I highly recommend not doing this, stock fuel pump is not friendly to this. But I was testing how high I can take the 60# injectors on E85 and small pulley TVS. But it does say how well this little regulator can handle.

When lowered to a low (normal) base pressure, the car idles like a dream. Also, when tuning for this, you take the same steps you would tuning a full return system.

Like I said, I didn't want to get into details, but just wanted to get the general info out. I have yet to see anyone post information regarding the kit, so figured I would for ZZP. If you want just performance, and don't care about the fancy regulator/gauge in the engine bay... This is perfect.

 

Thanks for the review. We will certainly keep your feedback in mind for future product development.

 

Do you need to adjust the regulator when installing just the option 1 also?

 

good info. Ill wait until those little problems are fixed then before i order lol

 

Most people never adjust them. They simply leave them at the base setting. They are actually loc-tite set before we receive them. Since we have a case here where adjustments are being made, maybe we could break them free at our shop, and then adjustments would be easier.

 

Those problems I listed are very, very little issues. I wouldn't let them prevent you from getting the kit. If you don't care about losing EVAP, just use the factory EVAP line as your vac line. The kit includes fittings to do so. Then there is no need to run any line at all.

The reason my T10 stripped was probably because I was fighting the loctite. Heat the thing up with a heat gun or something and I bet that loctite will get soft. It's only blue loctite.

 

Good stuff. is this product still available? at one point I believe it was off their site?

 

I have this sitting in a box next to me. Need to break the clutch in first. What pressure do these come shipped at?

Here is what is confusing me. Im sure with a little hands on time (thats what she said) I can figure this out.

So opt. 1 states that this little guy kicks in at 17.5 psi and then starts adding fuel, or 12 psi on the le5.

In opt. 2 it starts at a said base pressure and rises up with boost.

I understand that the trox bit on top adjust the fuel pressure, but how do you adjust the boost pressure it kicks in on in opt. 1? Thats whats confusing me. Im probably thinking to hard about it.

 

Regulator is preset at 4 bar.

 

Doesn't the factory fuel pressure regulator remove fuel pressure under vacuum? The Injector flow rate table in HPTs has boost and vacuum settings. Couldn't you just increase the slop of the table to get less fuel at vacuum and more fuel in boost?

Up to 17.5 PSI of course. After 17.5 psi there is no way to increase fueling with the stock PCM.

You mention having 42 psi of fuel pressure under vacuum. How low does the FP get using the stock PCM?

 

base pressure at the rail is 58psi

 

Yes. Base at 0 vacuum 0 boost. But doesn't Injector Flow rate table increase and decrease FP under boost and vacuum?

 

click.

 

x2.. about the option 1

 

well what is the base setting? Also How does it adjust if you have it done for the option 1?

 

I was under the impression its a straight 58lbs.

 

The factory regulator is always set at 58psi relative to atmosphere. The IFR chart in the ECM is in place to predict the flow rate based on manifold pressure. Every 1psi of boost is similar to a decrease of 1 psi fuel pressure as far as flow is concerned even though the rail pressure is still 58psi.

I recommending removing the in-tank regulator for anyone running our BRFP kit. It is the most consistent configuration and allows easier idle tuning when running large injectors.

 

That makes sense.

Hooked up like you mentioned (Option 2) Does the ZZP BRFP add fuel preasure like a slop under vacuum? Or is it designed to run the FP at 42psi until boost?

Sloped


Or like this?

 

So what is the base setting with the brfps?

 

is there any pros/cons to adjusting it with the option 1? I guess I just don't fully how it works for the option 1.

 

trying to fully understand it as well.

 

What changes need to be made in HP tuners to get this to work right, ive been wanting this part mainly to help idle my 80s without issue, I have no desire to do alot of tinkering I want the most simple configuration possible, I can disable EVAP codes with HPT

 

The same changes that need to be made when changing to a full return style at rail. It's been posted numerous times on this forum and HPT on what adjustments need to be made in HPT.

 

Thanks for all the info WSfrazier Ill hopefully be dropping my tank tomorrow and installing this if all goes as planned.

You said earlier that this comes preset at 4bar (58psi)? ZZPs website makes it seem like it comes preset at 42lbs. Not a big deal because Ill figure that out with a fuel gauge after its installed.

After a little research it seems that some people are using a base pressure around 42lbs. Would this be a good starting point for me? TVS 2.75 E85 80s?

Im guessing if I need more fuel I just raise the base pressure a couple pounds and the reset the tune and go again?

 

His was actually set for about ~51psi out of the box. We tried the exact setup you mentioned, 2.75" TVS pulley 80s and e85 with a 4 bar then a 4.8bar base pressure and the regulator puked before the tune was finished. Its only pulling about 2psi at idle off base pressure when theres about -9psi at the vacuum line.