More questions! sti inj+stock fuel rail on evo mani

[Poacher]

Hi guys

Another question, sti injectors (565cc) + stock fuel rail onto an evo 6/7 intake manifold and runners?

Will this work? It means i can use evo mani (bigger than ours) and keep the same inj etc. Otherwise i will have to source evo injectors + fuel rail + resistor packs + plugs for wiring! :(

Thanks
Johno

 

[stutzedward]

I've never came across this mod before. I know many (like you) has used pink STis on original manifold + fuel rail but on Evo manifold, unheard. Will there be a big difference in terms of improvement by using Evo manifold?

 

[Poacher]

Much better top end i would assume as it's bigger (longer) than ours, however our runners are longer giving better torque and response, shorter is usually better for top end.

 

[stutzedward]

Maybe you can be the first one to try out. If it works, then we can use as guide? Hehehe...

 

[Poacher]

I hate being Guinea pig... hahaha

 

[stutzedward]

Hehe.. there's always risk. But positive risk is fine. :wavey:

 

[4gbanger]

johno is true. my old boss(one of the most famous tuner at johor) once thought me that longer runner is better for torque n low end. shorter runner is better for high end rpm.

 

[Poacher]

I am pretty sure the much larger plenum will out weigh any difference and improve overall performance. I will have a look to install this weekend

 

[4gbanger]

larger plenum size also will improve engine response.. thats what i know..

 

[russellc2]

I'm just in the middle of doing this exact mod! using an Evo 6 intake manifold with no EGR ports and no MAP sensor housing, so I'm externally mounting the OEM map sensor for now and have ordered a aftermarket mount for this.

I'm stuck though with the fuel rail... the factory Airtrek one doesn't line up too well with the Evo intake manifold so I'm going to try and get hold of an evo fuel rail to see if that fits better. It may just be the black spacer / insulators that are too thick but I'll try the Evo rail first.

The Airtrek manifold is quite large with long runners compared to the evo. I think with forced induction the differences between intake runner length are not quite the same as with an NA engine so with a shorter / smaller intake the spool should be a bit quicker / more responsive which would make up for any losses??

I'll let you know how I get on and what you will need for the swap :)

 

[Poacher]

Thanks man! :) FYI ill be in Lower Hutt over christmas 22-28th we should catch up and compare mods :)

Johno

 

[4gbanger]

longer or shorter runner still can give effects on turbocharged engine.. thats what i know..
u should bought the evo manifold together with fuel rail last time.. or better get the aftermarket set..

 

[stutzedward]

After market fuel rails aren't expensive .... not sure if can use or not.

 

[russellc2]

I've ordered an aftermarket rail to try so I'll let you know how the fitting goes.

Yeah Johno keen as to catchup - hopefully I'm back on the road in the next few days!
I'm removing quite a bit of the factory vacuum lines along with EGR valve etc (after disabling in the ECU) so hope it all still works and no check engine lights :)

 

[stutzedward]

As you're altering some of the vacuum lines, will there be impact to engine performance like high-rev issue, idling, full boost etc? I think those stuffs are there for a reason.