ajm55

Guys, I'm at the end of my tether here. Any constructive advice will be appreciated. Excuse the prolixity, but you'll need the background.

I have a 2006 E55 which has been modded in 2 stages.

First-off mods were 168mm crank pulley, EC h/e, long tube headers, new bosch i/c pump, a decat and a tune. With these mods (using the Torco octane booster) we made 330wkw.

We’ve since added the TTM fuelling kit, the EC 82mm t/b, a belt wrap kit and the smaller s/c pulley and done a retune and we’re seeing more or less the same power output. In fact, leaving the 82mm t/b and fuelling kit in place and reinstalling the stock s/c pulley makes little difference to the power output.

Exhaust back pressure is 0.17 of a bar at just over 6,000rpm. We're seeing 10.7 psi boost at 6,000rpm.

I'm assuming that with the bigger t/b, smaller s/c pulley and a retune we should be seeing a significant increase in power.

NB: WE ARE AT 5500 FEET ABOVE SEA LEVEL!!!

BlkE55K

Box tune or custom tune? Same dyno and conditions? Are you tracking IATs and AFRs? They will tell you a lot about how the car is running.

chawkins2001

Hoezit boet, hoe gaan dit mannetjie Vie het jou motor getoon?

With your second round of mods, you should see a minimum of 35rwhp-45rwhp. First off with the upper pulley and 168mm lower, you should be seeing more boost than 10.7lbs, but that might be slightly attributed to been in Jo'Burg. The air quality up there is very bad.

Has the weather changed much between your last dyno, and your latest dyno with your new mods? Did you monitor IATS and A/F on your first go around of mods, and your second go around of mods?

Do you have a dyno sheet to share?

Was your car actually dyno tuned, or just received a canned tune, and you threw it on the dyno to verify the gains?

Are you seeing any CEL codes?

shardul

iTrader: (1)

Call me. Do you have my number from last time?

adianaty

Aside from Craigs requests also check to see if you have any boost leaks. Make sure your tune has the torque limiters removed as well.

ajm55

Craig, howzit brotha. Pulling my hair out here.

Just spoken to Shardul who has made some suggestions.

Cars with Rob Green Motorsport (RGM). They did the 1st batch of mods and the initial tune as well. The weather has changed between tunes but in a way which exacerbates the problem. The 1st tune was done in mid-summer heat whereas we are now at the back-end of winter and it's still pretty cold. My tuner will have monitored IATS and A/F first time around and now. He's pretty jacked and would, I'm sure be alive to any issues there.

So we're on the same dyno using the same tuner running the new mods in weather which is significantly more favorable.

I'll try and get the before/after dyno sheets for you guys to look at.

There's another 55 here with a 180mm crank pulley and stock s/c pulley running about 50whp more than me. I reckon I should be in that ballpark. I'm not technically minded but if you guys have any questions you think I should put to my tuner to help clarify things, please let me know.

Shot!

bnzuovr

How about a fault pump?

ajm55

PS: Jerry modified the stock file to remove torque limiters and shut the bypass valve etc but without touching the fueling and timing. Once the modified file was uploaded, my tuner dyno tuned

ajm55

Recently fitted the new bosch pump. Sure it's ok as IATS are in check

PACougar

If you could find out what your IAT's were and also log your spark advance it would help a lot to see what's going on.

Nachtsturm

Since the low PSI, belt slip?

GT-ER

Guys, he's likely seeing lower boost numbers due to the fact he's 5000ft above sea level. Seems very possible to me, although I'd check for belt slippage anyways.

HeissRod

Except that another E55 there made 50rwhp more than his car with less mods?

cij911

I have a 175mm pulley and log a lot. At sea level @ 6,000 RPM my boost is ~11.1x psi.. If I recall correctly the 168mm pulley + the smaller SC pulley is ~175mm pulley. The fact that you are able to see 10.x psi @ 5500 ft. is great.

What I have seen is just a few runs and these cars get heat soaked pretty good. So depending on your ambient temperature and how many runs you did, you could easily see a drop of ~30+ hp.

Log IATs and install a split cooling setup.

ajm55

Thanks for all the feedback.

I'm waiting on the delivery of a FabTech trunk tank so that I can split the cooling. I'll ask my tuner about the IATS in the meantime but I'm confident he is logging them and there's no issue there.

If the boost cij911 is seeing at sea level is what one should expect with a 175mm pulley (i.e. 11.1x psi) then the boost we're seeing on a 168mm pulley with the smaller s/c pulley at 5,500 ft is probably as good as I can expect, is it not?

Assuming the IATS are in check (which I believe they are), what is really puzzling is why the addition of the 82mm throttle body and the smaller s/c pulley are not showing any power gains over the same set up except with the stock t/b and stock s/c pulley. I've been told that the addition of the 82mm t/b will only show a few hp on the dyno but make a significant difference on the road. Even assuming this is so, surely the addition of the smaller s/c pulley should result in a noticeable gain on the dyno?

Again, I'm guessing I should be in the same ballpark as the 55 with a 180mm pulley and I'm 50whp down.

As for belt slippage, the boost seems to peak at around peak torque and then dip slightly after that but I think this is normal?

Anyway, I'll make sure about the IATS and spark advance and try and get the before/after dyno sheets posted.

Toadster

what about your AFR?

ajm55

My tuner knows his stuff and assures me that the AFR is where it should be. I'll check to see if I can get the details from him

cij911

Well assuming all other factors to be the same, I can guarantee your IATs are not good. With a factory setup and EC heat exchanger, running an effective ~175mm pulley setup, you will get serious heat soak after just a few dyno pulls. Once your IATs go above 130, which they did, you will start pulling timing something fierce. On the stock setup, with ambient in the high 90s, with an EC heat exchanger and Bosch 010 pump, my IATs will start ~110 and quickly shoot past 160 if I do a few back to back pulls. It takes a while for them to get back down to 115 range too. I too am waiting on an IC engine tank install with the hopes of keeping my IATs below 130.

In addition, with regards to the 180mm pulley car, were its results done on the same day and on the same dyno?

PACougar

I agree, I don't think his IAT's would be very could either. Also a 168+a smaller SC pulley should be close to a 181mm-183mm pulley, and dyno runs are about as bad as it get for heat soaking an engine!

Hasan Shaikh

Do you feel more power while driving?

Dynos can be stupid at times.

99lightning

Yes they can be for what ever reason. I have a dyno and i already experienced with my saleen at the time when i made some changes no increase in power yet picking up mph and et at the track.

GT-ER

You need to datalog.

What is your A/F ratio?
What is your timing like?
What fuel are you using?
What is you boost like ( 10.7psi peak or at the upper rpms )?

Also, are your air filters clean?

chawkins2001

Sending you a pm boet.

skratch77

Car is in a limp funk happened to me a few times...its from the tb when it pends codes.

Clear ecu and see if it helps.

10 bucks says your car is pending a few tb codes

ajm55

An update:

The problem is defnitely not heat-soak. IATS are in check (around 120 degrees max) and there's no retarding of the timing.

Air flters are new.

Today we reinstalled the stock s/c pulley but left the TTM fuelling kit and 82mm throttle body in place. We ran the car in weather more favourable than that which we had when doing the dyno run after the first round of mods. We are down on power throughout the rev range with the loss ranging from 11whp to 18whp.

On Monday, we'll reinstall the stock injectors and re-run the car. If still down on power, we'll reinstall the stock throttle body and reassess.

Probably a stupid question but please indulge my limited understanding of how these things work: I had the 82mm throttle body and TTM kit installed by a Merc dealership in the area. On starting the car after the installation, the idle was extremely rough and noisy and there was quite a bit of spluttering. A host of codes appeared - don't know which. The Star device was then hooked up and the end result was that the idle was smoothed out.

Car then went to my tuner for a remap. After battling for some time, my tuner removed the t/b, s/c and TTM kit. He found that the injectors had been pushed too far up into the fuel rail and were therefore not sealing properly. He addressed this problem and reassembled. He has not however hooked the Star device up at any time after reassembly. Could these events have anything at all to do with the problem?







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