PutNavid

Hey guys, trying to decide what to next on my e55. I was thinking of doing a throttle body but im leaning more towards another pulley. Currently I have kleemann headers and fully catless, 84mm sc pulley, bwk, and an he. I was thinking 77mm pulley but would it be wise to do 550 injectors at this point and maybe a looped rail? Any suggestions would be appreciated!

Hammer Down

How's your cooling?

BlackHammer

+1

More boost = more heat = more heat = faster the car pulls timing/falls on its face.

In many cases more boost = slower car.

Ton's of threads on "IAT's". Please read them.

TK

PutNavid

Currently I'm on the new 010 pump, plm he, and split cooling on the small BMW tank. If I go down to 77 I will for sure be going with a tank. Most likely the engine bay tank and if needed I would do the auxiliary heat exchange from vrp. Besides cooling would I be okay on my current injectors or would they need to be 550?

BlackHammer

If you have the stock crank pulley you SHOULD be OK with the stock injectors but wait for others to confirm.

Also, just saw the new C&D; he new ZL1 has 11 (yes, eleven) heat exchangers!

kustom2k1

How many miles on the car? It helps if you log after your tune so you can get an idea how rich or lean the tune is.

PutNavid

The car has a stock crank pulley. just rolled 87000 miles. And I am looking into buying a zeitronix zt2 to keep track of afrs.

kustom2k1

To be on the safe side, I would wait until you have the ability to log. Why take a chance and cause a catastrophic failure. Know that your not starving the motor of fuel instead of guessing. Logging equipment is cheap insurance.

PutNavid

very true. Theres currently a group buy going so I could snag one up. Would it be smart to put the sensor on the drivers side bank since cylinder 8 is always the one to go?

kustom2k1

Yes drivers side since it may be the lean bank.

PutNavid

I was recommended by Tony to do a looped rail and I should be good. The zt2 should alleviate any worries.

Hammer Down

there's a big debate over the looped fuel rail. I look at it this way it couldn't hurt so why not? I have it. I've had my mods for over 4yrs now.

M3diesel

Just do a looped rail. There really isn't no debating it. Why would they have it on the SLR from the factory which is essentially the same engine in the 55's if it wasn't necessary along with the SLR's slightly larger injectors?

A supercharger pulley is a waste of money but you better get a looped rail, injectors, trunk tank anda killer chiller/dry shot if you want to have any chance of not experiencing detonation in your engine

PutNavid

What is done to your car exactly?

dont you think my mods are a little conservative though? I mean it's pretty much going to be a 77 and mid length headers not even long tubes. My buddy's car which he bought recently has been running a 180cp since like 2010 on stock fuel, and just split cooling and an added smaller heat exchanger.

M3diesel

True so if you are not going to continue to modify your car then just a looped rail with stock injectors and a retune should be fine.

SICAMG

It's all on how you drive your car as well. That plays a huge roll in it.

PutNavid

knowing me I'll want to do more to it later on but since I'll be okay for now I'll worry about later when the time comes lol. Thanks for your input!

Hammer Down

my old buddy bassn07 (Alan) was one the first guys in the 10's and he didn't have a fuel rail. My setup is essentially the same as his except I have a fuel rail with a 185 pulley with 550 injuectors and he had a 180 with SLR injectors. RedBullJkny didnt' have a fuel rail and his mods before TT are well documented. For a list of some of the best setups do a search on a 10 second club or something like that.

PutNavid

will do. I mean injectors aren't super expensive vrp has them for 300 bucks if I'm looking at the right ones but I just don't wanna do something if I don't need it at the moment. If I do these mods without injectors then an indication of me needing bigger injectors would be the car running pretty lean at wot correct?

BC928

The theory out there on the looped rail is that the "end" of the rail doesn't get as much fuel as the beginning. Or visa versa. So the looped rail does a few things, few of the people I have seen post actually know which is the fix:

1) Increase volume of fuel in the rail.
2) Flow of fuel does not "dead end" at number 8.


I don't know which one it is.

I also believe that a larger supply line is a good play as well.

PutNavid

i think you might have it backwards. Correct me if I'm wrong but the fuel supply point on the rail is closest to cylinder 8. Since the fuel has to travel to the rest of the fuel rail the closest injector (8) gets the least amount of pressure so the looped rail should equalize the pressure. Again correct me if I'm wrong but that was my understanding of it.

BC928

I can look when I get home. I think you are right about placement. But how is that the reason 8 has an issue? Closest gets the least pressure?

I understand this is a proven problem, but who know why this is the solution?

PutNavid

i think it's because it's easier for fuel to travel further down the rail than it is to go through the injector for 8. I don't know it just makes sense in my head lol because you would think the problem would be at the two cylinders at the end of the rail.

PutNavid

So after a ton of research ive decided if I do go with the 77mm pulley, I will be doing a looped rail and also 550 injectors. I always seem to read horror stories and worry myself more than I should but better safe than sorry! Should I be worried at all if I do injectors and looped rail? I bought the zeitronix yesterday so I will be looking at afrs constantly...

Hammer Down

Maybe I missed it but have upgraded your tb to a 82mm?