V1 OTTP Billet Fuel Rail and Fuel Rail Fitting (LSJ)

[finazzoty]

Hi guys,

Is anyone aware of the purpose of these two parts from OTTP?

1. https://www.overthetopperformance.com/Fuel-Rail-Fitting-LSJ_p_101.html
2. https://www.overthetopperformance.com/Ecotec-Billet-Fuel-Rail_p_100.html

-Tyler

 

[Ross]

That is mostly bling.
The fuel rail is mostly hidden under the black "Supercharged Ecotec" cover.
The stock one has a pulse damper, which smooths out the fuel pressure as the fuel pump and injectors both have a pulse effect.
The fuel rail connects the fuel line to the top of each fuel injector. I guess it has a limit as to how much fuel it can deliver, but you would need to have huge injectors to hit that limit. I think most people buy it because they want the bling, and the AN connectors for their high pressure/high volume fuel pump, which also has AN connectors. Maybe someone who has one can chime in and explain a reason for buying it.

yin

 

[RCK605]

The fitting can be installed on the stock rail to use it with a return style fuel system. I believe the billet rail has higher flow capabilities and ports at each end for a return style system.

 

[finazzoty]

@Ross I kinda figured as much with the blink aspect. So with 80# injectors, this is not necessary?

Also, I see you have the high voltage coils - not sure what levels of boost of boost you’re running, but wondering if this would be necessary with a Z54 on E85? Probably in the neighborhood of 20 psi…maybe a bit more

 

[RCK605]

@Ross I kinda figured as much with the blink aspect. So with 80# injectors, this is not necessary?

Also, I see you have the high voltage coils - not sure what levels of boost of boost you’re running, but wondering if this would be necessary with a Z54 on E85? Probably in the neighborhood of 20 psi…maybe a bit more

@finazzoty I am assuming since you mentioned them that you will be running a Z54, E85, and 80# injectors? If so, I would run the billet manifold and boost reference fuel system. Might not be needed for 20psi, but good insurance to not have fueling issues and gives headroom to grow.

 

[finazzoty]

@finazzoty I am assuming since you mentioned them that you will be running a Z54, E85, and 80# injectors? If so, I would run the billet manifold and boost reference fuel system. Might not be needed for 20psi, but good insurance to not have fueling issues and gives headroom to grow.

Awesome thank you - so do I also need that fitting?

 

[RCK605]

You shouldn't if you are doing boost reference and return style. When you decide on a fuel system look what comes in the kit and how it is supposed to be hooked up.

 

[Tinkles]

That fitting is one of the very few OTTP parts I have and adds to the reason I dislike OTTP. Unfortunately I do not have time tonight to explain further.

 

[Ross]

@Ross I kinda figured as much with the blink aspect. So with 80# injectors, this is not necessary?

Also, I see you have the high voltage coils - not sure what levels of boost of boost you’re running, but wondering if this would be necessary with a Z54 on E85? Probably in the neighborhood of 20 psi…maybe a bit more

Nah, not necessary. I bought some bling. Some owners complain the high voltage coils have a shorter life than the stock coils.
80lb/hour injectors work fine on the stock fuel rail. Up to you if you want some bling.
A boost reference fuel system is recommended on 80lbs/hr injectors, as it will help with idle, and help with max fuel output. Most 80lb injectors won't do a normal idle without a BRFS, as those injectors have a hard time delivering small amounts of fuel.

 

[Desert Sasqwatch]

That fitting is one of the very few OTTP parts I have and adds to the reason I dislike OTTP. Unfortunately I do not have time tonight to explain further.

OTTP recently did me wrong too and I'm now out almost $100 because of their 'return' policy. Might as well keep what you ordered if it's wrong, it'll end up costing more to try to return it - and then they may not even accept it back! Avoid OTTP if possible.

 

[finazzoty]

Ah jeeze - Saw all this after I already pulled the trigger on these. I don't have a ton of parts from them, but definitely have some. Hopefully nothing I regret later down the road

 

[jirwin]

Nah, not necessary. I bought some bling. Some owners complain the high voltage coils have a shorter life than the stock coils.
80lb/hour injectors work fine on the stock fuel rail. Up to you if you want some bling.
A boost reference fuel system is recommended on 80lbs/hr injectors, as it will help with idle, and help with max fuel output. Most 80lb injectors won't do a normal idle without a BRFS, as those injectors have a hard time delivering small amounts of fuel.

How does BRFS help with idle? Wouldn't it be the same fuel pressure at idle as without it? Or am I missing something?

 

[Ross]

BRFS will have low fuel pressure at idle, which will allow large injectors to dispense smaller amounts of fuel.
The fuel pressure will rise as the boost rises in the intake. So no boost at idle means low fuel pressure at idle.

For example:
A stock LSJ fuel pump is 60PSI at all boost levels... which is about -10 PSI to +12 PSI... a 22PSI range.
With BRFS on a stock pump, idle would be 38PSI, and full throttle boost would be 60PSI.

 

[Gtstorey]

You would typically set a referenced fuel system as a 1:1 so the pressure difference the injector sees is always the same, add 10psi of boost, the rail pressure goes up 10psi.

 

[Ross]

Isn't that what I my example did? A constant 48PSI difference between the intake and the fuel pressure.

 

[Gtstorey]

I was to tired to do the math.

 

[Tinkles]

My grips with the fitting. A minor one is that there was no option for having it coated and I had to use my Cerokote guy. 2nd, no installation instructions were included. OTTP says installation is easy to figure out and for me, it was, but seeing as it is a fuel system part and incorrect installation can cause a leak that could result in a major fire. Having a set of installation instructions to confirm everything is a nice piece of mind. My biggest grip is that it -6 ORB. Why not -8 ORB or -10 ORB? Because OTTP determined that no Ecotec needs an -8 or larger fuel system. Going to the largest ORB fitting you can fit allows the end user to use whatever size line without running the risk of chocking down their fuel system. Now I have to modify a perfectly good -6 ORB to -8AN fitting to ensure no fuel supply issues. Yes, technically using the pulse damper end is feeding fuel into the wrong end of the stock fuel rail, but in my defense the proper feed side is alot more restrictive for a -8 feed line.

Unfortunately OTTP was the only place that I could find that fitting. I removed the stock fuel pressure regulator and pulse damper from my LSJ fuel rail to run an aftermarket Radium Engineering FPR/PD combo with a -8 AN feed and -6 AN return. The LSJ fuel rail is the only "stock" part in my fuel system. My whole fuel system should be overkill which is what I want.

In my 15 years of messing with these Ecotec engines I have never heard of the fuel rail needing to be upgraded. With how beefy the stock L61 and LSJ rails are, I would not be surprised if that OTTP rail actually flowed less fuel.

Ah jeeze - Saw all this after I already pulled the trigger on these. I don't have a ton of parts from them, but definitely have some. Hopefully nothing I regret later down the road

Here is another kick in the nuts. That fitting is only for the LSJ fuel rail and will not work on that aftermarket fuel rail. Also you will need an external fuel pressure regulator/damper combo to run that fuel rail. This is what I have and am very happy with it. Yes there are cheaper options, but Radium's products are extremely nice. Some of the best parts in the market.

That fitting deletes the pulse damper and will allow you to run a fuel return line to the tank. The pulse damper smooths out the spikes in fuel pressure which can occur from the injectors opening and closing. Your car will run without it. But you can run into fueling issues without it.