Questions about WMI and PI.

[Randomizer2]

So eventually I want to gain more than 400WHP on an n54. I have some questions that will help me plan everything out.

1. at what WHP is PI needed?
2. Are there any alternatives to PI?
3. Can I have WMI and PI at the same time? I do not have e85 in Canada.


I plan on skipping the JB4 entirely and going with a MHD custom tune from wedge performance.

[Petro135]

If you dont have e85 then i think PI is pretty much a waste. It just uses more gas. You use it get more of that high octane fuel to your engine. I have e85 but 1 station 45 min away so im not dealing with it. I have chargepipe meth now and im upgrading to the pro-meth direct injection. Which depending on your % of water to meth is how much extra octane you have. Guys are running 100% meth and i dont know their octane but im guessing its well over the 116 mark.
But in answer to you original question. I believe 550whp is the cut off mark to need PI if running e85 mixes

[Randomizer2]

Originally Posted by Petro135

If you dont have e85 then i think PI is pretty much a waste. It just uses more gas. You use it get more of that high octane fuel to your engine. I have e85 but 1 station 45 min away so im not dealing with it. I have chargepipe meth now and im upgrading to the pro-meth direct injection. Which depending on your % of water to meth is how much extra octane you have. Guys are running 100% meth and i dont know their octane but im guessing its well over the 116 mark.
But in answer to you original question. I believe 550whp is the cut off mark to need PI if running e85 mixes

I thought that PI was to add supplemental fuel to the engine because the stock injectors are maxed out. Am I wrong? Even if I am on pump ill eventually run out of injector capacity.

[Petro135]

Youll not get to that point on stock turbos with pump gas. All you need is a walbro pump in your lpfp bucket.
Im doing stg2 turbos, 93 oct , walbro 450 in a diy bucket and ive got plenty of fuel

[Randomizer2]

Originally Posted by Petro135

Youll not get to that point on stock turbos with pump gas. All you need is a walbro pump in your lpfp bucket.
Im doing stg2 turbos, 93 oct , walbro 450 in a diy bucket and ive got plenty of fuel

I know I won't. I said I was planning for single turbo and alll of its requirements.

[Petro135]

Originally Posted by Randomizer2

I know I won't. I said I was planning for single turbo and alll of its requirements.

I still dont think PI benefits you unless your running e85

[Randomizer2]

Originally Posted by Petro135

I still dont think PI benefits you unless your running e85

Say I had a goal of 600-800whp. I would need to add more fuel somehow right? Wouldn't the stock injectors be maxed out?

[Petro135]

You need either e85, race gas or meth to make those big power numbers. Need more octane then more fuel

[Randomizer2]

Originally Posted by Petro135

You need either e85, race gas or meth to make those big power numbers. Need more octane then more fuel

I would be running pump with meth, I dont have e85 in canada

[Petro135]

Thats what i was saying. If you dont have e85 run direct port meth and you will get all the octane you need

[Randomizer2]

Originally Posted by Petro135

Thats what i was saying. If you dont have e85 run direct port meth and you will get all the octane you need

I see. Ideally eventually my end goal is 800whp. For fueling I would get direct port meth injection. My injectors won’t me maxed out? Kinda confused as on other platforms I see injector upgrades being pretty common.

[drwillb]

Originally Posted by Randomizer2

I see. Ideally eventually my end goal is 800whp. For fueling I would get direct port meth injection. My injectors won’t me maxed out? Kinda confused as on other platforms I see injector upgrades being pretty common.

You are going to face two separate but linked problems.:

1. Pump gas does not have enough octane to support the kind of HP you are looking for.

2. Typically, e85 is used to bring octane up but, at the same time, e85 forces you to add more fuel because it has much less total energy content/potential than straight gasoline.

This is why you have to add PI, to make up for the lower energy even though you have higher octane. Adding more straight gas doesn’t help because you’re not doing anything about the octane. You go to race gas for the octane without needing additional flow but you’ll spend your money at the pump instead of on parts for the motor.

The pump upgrades are needed to support the increased flow demands brought on by the corn juice or high HP/psi.

I think that sums it up.

[Randomizer2]

Originally Posted by drwillb

You are going to face two separate but linked problems.:

1. Pump gas does not have enough octane to support the kind of HP you are looking for.

2. Typically, e85 is used to bring octane up but, at the same time, e85 forces you to add more fuel because it has much less total energy content/potential than straight gasoline.

This is why you have to add PI, to make up for the lower energy even though you have higher octane. Adding more straight gas doesn’t help because you’re not doing anything about the octane. You go to race gas for the octane without needing additional flow but you’ll spend your money at the pump instead of on parts for the motor.

The pump upgrades are needed to support the increased flow demands brought on by the corn juice or high HP/psi.

I think that sums it up.

Yeah, I pretty much understand that. I just don't know what fueling upgrades ill need for a high hp build on pump + meth. Most builds I see online are all e85.

[Petro135]

Originally Posted by Randomizer2

Yeah, I pretty much understand that. I just don't know what fueling upgrades ill need for a high hp build on pump + meth. Most builds I see online are all e85.

Im doing the same thing as you. Single turbo, direct port meth because e85 is too far for me to drive all the time.
Only upgrade in my fueling for now will be the lpfp with a walbro 450 i already have in the car. Then i will do some logs and see where my fuel is.
If im running out i will buy the PFS diy dbl bucket and add a walbro 525. So my primary pump is a 525 and my secondary will be a 450 that only turns on after im well into boost. That should be plenty of fuel. Im not looking at 800whp though. If be more worried about the motor and trans blowing at that power than the fuel. Im looking at 650whp and then a 700 area race map.

[Randomizer2]

Originally Posted by Petro135

Im doing the same thing as you. Single turbo, direct port meth because e85 is too far for me to drive all the time.
Only upgrade in my fueling for now will be the lpfp with a walbro 450 i already have in the car. Then i will do some logs and see where my fuel is.
If im running out i will buy the PFS diy dbl bucket and add a walbro 525. So my primary pump is a 525 and my secondary will be a 450 that only turns on after im well into boost. That should be plenty of fuel. Im not looking at 800whp though. If be more worried about the motor and trans blowing at that power than the fuel. Im looking at 650whp and then a 700 area race map.

Yeah, I know 800 is a stretch on stock motor though I hope to get a built one one day. Isn't the hpfp the one that feeds the injectors? The point of PI is to get more fuel because the injectors are maxed out right? How does upgrading the lpfp help? Sorry im pretty confused when it comes to this direct injection platform lol.

[iminhell1]

PI is to supplement the limitation of the HPFP. Not the injectors. The injectors have been proven north of 800whp, reliability up there ?.

Pretty much anything north of 500 you'll want/need some type of supplemental fuel, or a way to overdrive the stock HPFP (Spool or PFS keeping stock locations of the pump).

If you want to stay Di only, then Dual HPFP's is your only option, Vargas DBBL.

If you want to do PI/Meth it would really seem JB4 is the path that should be looked at. It can control either (not both?). It's a more cost effective route to the same goal.

[Randomizer2]

Originally Posted by iminhell1

PI is to supplement the limitation of the HPFP. Not the injectors. The injectors have been proven north of 800whp, reliability up there ?.

Pretty much anything north of 500 you'll want/need some type of supplemental fuel, or a way to overdrive the stock HPFP (Spool or PFS keeping stock locations of the pump).

If you want to stay Di only, then Dual HPFP's is your only option, Vargas DBBL.

If you want to do PI/Meth it would really seem JB4 is the path that should be looked at. It can control either (not both?). It's a more cost effective route to the same goal.

If I go with PI, how can meth and 94 octane be sprayed at the same time? Am I missing something?

[Petro135]

You are right you cant spray both. But you can spray meth in the chargepipe for cooling and then PI in the manifold tubes. But again without e85 your wasting your money on PI. Like iminhell1 said you would need a booster for your hpfp instead. Look up vargas dbbl barrel or helix or PFS pod. I think the best solution for you is a stage 3 lpfp. A pod or helix or one of those to upgrade your hpfp and then a direct injection meth setup into all 6 cylinders. Look at pro-meth or a snow performance plate. You can also get a phoenix manifold and take out the PI injectors and add meth nozzles once you realize PI isnt helping you

[Randomizer2]

Originally Posted by Petro135

You are right you cant spray both. But you can spray meth in the chargepipe for cooling and then PI in the manifold tubes. But again without e85 your wasting your money on PI. Like iminhell1 said you would need a booster for your hpfp instead. Look up vargas dbbl barrel or helix or PFS pod. I think the best solution for you is a stage 3 lpfp. A pod or helix or one of those to upgrade your hpfp and then a direct injection meth setup into all 6 cylinders. Look at pro-meth or a snow performance plate. You can also get a phoenix manifold and take out the PI injectors and add meth nozzles once you realize PI isnt helping you

I was doing some googling about the vargas dbbi and its hard to find positive things about it lol. If my goal is 800whp I can spray meth in the cp and pi in the manifold. This will work right? Why do you say PI won't help me at the end?

[Petro135]

Because you still wouldnt have enough octane. Buy a huge single turbo and no matter how much fuel you can get to your engine. You wouldnt have the octane to get over 550-600hp. Chargepipe meth helps some but mostly in cooling iat's.
Run port, the biggest turbo you can find and loads of boostane octane booster. And youll still need a bigger lpfp to get the fuel to your hpfp

[Randomizer2]

Originally Posted by Petro135

Because you still wouldnt have enough octane. Buy a huge single turbo and no matter how much fuel you can get to your engine. You wouldnt have the octane to get over 550-600hp. Chargepipe meth helps some but mostly in cooling iat's.
Run port, the biggest turbo you can find and loads of boostane octane booster. And youll still need a bigger lpfp to get the fuel to your hpfp

So theres a difference between chargepipe meth and direct port injection meth then. That makes more sense. So if I run direct port injection meth, ill be at a fuel limitation so then I need a hpfp upgrade? Am I understanding this?

[iminhell1]

Well I'm going for 800whp and I'm going the DBBL route. From the tuning standpoint, complexity and such I felt it was the least complex and therefore easiest for me to tune.
I'm taking my sweet time though.