Just wondering roughly what psi boost can be raised to with regards to 555 injectors? I realise its a completely different question as regards supporting mods etc

I don't think you can max them out on stock turbos?

 

Stock turbos become all horribly innefficient after 16psi anyway...

Just wondering roughly what psi boost can be raised to with regards to 555 injectors? I realise its a completely different question as regards supporting mods etc

 

on the turbos you have i would have thought they would run out of puff at around 1 bar

Surely it dosn't mater what turbos are used. I understand different turbos would get to ' said' pressure in there own way, or have i not got my head around this properly?

I just done abit of internet reading and i think i understand.

Using bigger turbos keeps the heat down which changes the 'air' which in turn produces more power.

This is well complicated!

Yep - it's too complicated to say "they run out at Xpsi" really - it's a factor of air density (which is a factor of temperature & pressure) and the tune - you could have a tune pumping more fuel in to counter knock from too much advance, or a tune putting less fuel in because there's less knock due to less ignition advance..

 

That said, stock or near stock turbos are likely to be outside efficiency some way before you max 555's, as said above.

I've got greddy 18g's from mike so i better be careful i think!

It's easier to ask what HP injectors max out at, by the way - for which RC Eng have a calculator here:

http://www.rceng.com/technical.aspx

It's easier to ask what HP injectors max out at, by the way - for which RC Eng have a calculator here:

http://www.rceng.com/technical.aspx

 

according to that calculation for a genuine 500 rwhp and keeping at a safe 80% injector duty and keeping the stock fuel pressure you will need approx 720cc injectors

Yep i had a go on that and got more confused! I put in 550hp at the crank and it said around the 720 mark needed! I thought with 555's you should get about that back in hp, even if abit towards its limit maybe.

i dont think that chart conversion is correct. :confused:

Surely it dosn't mater what turbos are used. I understand different turbos would get to ' said' pressure in there own way, or have i not got my head around this properly?

 

its to do with flow and pressure not just one on its own, a small turbo may flow 200cfm at 16psi and be out of its efficiency range, a bigger turbo could be flowing 200cfm by 7psi so you cant use pressure on its own to work out when injectors will be maxed out

Yep i had a go on that and got more confused! I put in 550hp at the crank and it said around the 720 mark needed! I thought with 555's you should get about that back in hp, even if abit towards its limit maybe.

 

 

555's would be above their limit at that ponit it would be cheaper and a better insurance to get bigger injectors!

Just had another go at that conversion and 420hp = 555 injectors.

So am i right in thinking when shes back on the road the main thing is not to run over 80% duty cycle on the injectors? ie:start with low boost and work up to find the safe highest boost for the injectors?

So am i right in thinking when shes back on the road the main thing is not to run over 80% duty cycle on the injectors?

Yes you are right in thinking that Chris! How the car coming along? The last time I saw it the Turbos were still in there box and you were still running the stocks with 360* bearings :)

Just had another go at that conversion and 420hp = 555 injectors.

So am i right in thinking when shes back on the road the main thing is not to run over 80% duty cycle on the injectors? ie:start with low boost and work up to find the safe highest boost for the injectors?

 

So won't my 550cc's be any good for 500hp +? :(

555s are good for ~500rwhp ie power at the wheels....

555s are good for ~500rwhp ie power at the wheels....

 

What duty cycle would they be running at 500bhp?

80% apparently Mark

555s are good for ~500rwhp ie power at the wheels....

 

Er translation to flywheel figure on manual box??? Pretty please

Errrrr about 600ish BUT flywheel bhp is not important, its the power at the wheels that counts! Unless of course you're just after bragging rights at the bar ;)

Errrrr about 600ish BUT flywheel bhp is not important, its the power at the wheels that counts! Unless of course you're just after bragging rights at the bar ;)

 

Phew, thought I was going to have to sell the injectors before I even got them!! Just wanted to make sure as the turbo set up will deliver upto 600-650 so 600 at the fly is ok.

 

No, at bragging rights it would be 700+ at the start of the night rising to 800 by midnight :tongue:

Just remember that you don't want to be pushing the turbos right to the ragged edge ;) They will last a LOT longer and so will the rest of your engine if you run them at 80-90% of their capability :)

Just remember that you don't want to be pushing the turbos right to the ragged edge ;) They will last a LOT longer and so will the rest of your engine if you run them at 80-90% of their capability :)

 

Dam, may have to go bigger turbo.....

You WILL regret it! There are relatively few turbos that suit the VG30DETT in terms of driveablility...........

You WILL regret it! There are relatively few turbos that suit the VG30DETT in terms of driveablility...........

 

:( foiled again