Bigger injectors or 4th injector, what's better on a turbo?

[cannondale27]

The factory regulator is in the tank, to add and external one you have to disable the one in the tank and add a return line to the tank, back to the surge canister to keep it full of fuel.

One reason the stock pump has a hard time keeping up is because they are using alot of fuel volume to make the siphon to work in the surge canister, it by passes through a venturi to make a siphon to keep it the canister full

I am sorry. Yes regulator is in the tank. So when upgrading the pump itself is still used but they are going to a return system and keeping the pump right?

 

[Studroes144]

Ok so looking like I gotta open up the stock injectors instead of the 4th injector if it's not a quick simple hook up. I'd have a hard time believing there's any real advantage or disadvantage when comparing the two. just figured it'd be nice not to change the stock injectors but now I have my answer.

 

[Srxspec]

Have run both setups. 430cc injectors with proper map works well with standard PCV PTI. I also have Dynojet specially made PCV PTI with extra injector plug-in as well that works very good also. Regulator upgrade with 430cc injectors is enough fuel to support 300 hp. I also have 550cc injectors & mapping for those looking to go big big boost.

 

[shadow637]

Ok so looking like I gotta open up the stock injectors instead of the 4th injector if it's not a quick simple hook up. I'd have a hard time believing there's any real advantage or disadvantage when comparing the two. just figured it'd be nice not to change the stock injectors but now I have my answer.

I would go with new 430's from Ulmer and use his map. Then you still have your stock injectors if you ever pull the turbo off and return to stock for resale.

 

[Studroes144]

I would go with new 430's from Ulmer and use his map. Then you still have your stock injectors if you ever pull the turbo off and return to stock for resale.

Can't picture that ever happening, engine is setup to low compression now so would be hard for resale. Good thought tho for sure

 

[stingray719]

As far as fuel pump what I see some doing is just going from a single returnless system to a return system which allows a external regulator. I find it hard to believe that the Pump itself will not provide enough fuel to support our engine. Our regulator is in the rail. Was it MPI that did that? What PSI are they running? Is stock the standard 42-45psi?

EVO blocks off the regulator in the tank and adds an external regulator and return to tank.

 

[shadow637]

Can't picture that ever happening, engine is setup to low compression now so would be hard for resale. Good thought tho for sure

Understood! Do you have someone to write you a good base map for modded stockers?

 

[Studroes144]

Understood! Do you have someone to write you a good base map for modded stockers?

Starting from zero on a dyno, starting at 4.5 pounds to try out some exhaust comparisons and then turning it up from there.

 

[Joe ltx-le]

I'm going with new 430 cc injectors with allens pcv pti with his tune.

Can wait o try these sled out. Summer sucks.

 

[Studroes144]

Allens tune is spot on! Only adjustment we made was leaning it out just a tad on top. But it's was good and safe with plenty of fuel. I'd recommend the fuel pump upgrade while you're in there, then you know it's done and you'll never need more fuel.

 

[Joe ltx-le]

Allens tune is spot on! Only adjustment we made was leaning it out just a tad on top. But it's was good and safe with plenty of fuel. I'd recommend the fuel pump upgrade while you're in there, then you know it's done and you'll never need more fuel.

Allen said that the injectors will operate fine with the stock pump.

I hear what your saying though. Then it's done.

Good bye gems

 

[Studroes144]

On lower boost levels for sure. I forget exactly what hurricane Dave said but I believe he said they were good up to 230 hp with stock pump. Unless you never plan on going over that than no big deal but you already know how addicting that power is!

 

[Joe ltx-le]

Im hoping I won't get worse fuel mileage then I am now with the gems. I know bigger injectors mean more fuel.
The gems was so rich from the start hopefully it will even out to a better tune and close to the same mileage.

Any insight?

 

[Studroes144]

Im hoping I won't get worse fuel mileage then I am now with the gems. I know bigger injectors mean more fuel.
The gems was so rich from the start hopefully it will even out to a better tune and close to the same mileage.

Any insight?

I get better mileage than a stocker, taller gearing helps on that. When trail riding I find I'm rarely much over half throttle, it just cruises so easily. 60-70 mph cruising at half throttle is nothing.

 

[Joe ltx-le]

I get better mileage than a stocker, taller gearing helps on that. When trail riding I find I'm rarely much over half throttle, it just cruises so easily. 60-70 mph cruising at half throttle is nothing.

Good to know. Thanks. I found with the gems setup, in northern newbrunswick ( 70-100mph roads)I would burn so much I was running out first out of everyone. Like 95 miles to a tank. But I never really cared. It was the fastest until I ran out of fuel haha.