GT-ER

After installing a 2.5" pulley on the kleeman setup and beating the living hell out of the car for a week ( litterally about 50 wot runs to 100+mph in one week ) the car began misfiring. Here are the compression results:

1 = 170
2 = 170
3 = 173
4 = 175
5 = 165
6 = 145
7 = 171
8 = 97

cyl 6 seems weak ( engine has 105k miles and ran nitrous before the supercharger ). Cyl 8 is toast however. Car ran fine though even after the damage. It's always number 8 isn't it.

Keep in mind, AF ratio was high 10's and timing was a ridiculously low 7-9* with 0* of timing retard due to knock up until 3rd gear where it would sometimes retard 1-2* or so in small bursts which isn't bad at all. I guess the engine was just tired.

benzmodz

That's a bit like saying that if you hit your partner with a baseball bat a few times you can see how weak they are.

These engines are not designed for nitrous or for racing style performance 24x7. At least not without oxygen sensor deletion, straight through exhaust, high flow cat, and exhaust headers.

MBfinatic

OUCH! What is the plan for it now? Machine shop?

GT-ER

Oh I know, it is what it is...lol.

He has headers, straight dual exhaust with no cats. I also tried to play it as safe as possible and it still blew...ouch.

The Kleemann Eaton currently has a 2.5" pulley ( stock is 2.8"" ).

E55 Pistons and rods.

91RS

Wow. That's crazy. I guess I should leave mine alone and be happy with it.

Are the heads different on the E55 or just the rods and pistons? It might be a good idea to go with forged pistons, especially if the car is still going to be driven that hard.

Quickvr4

Uh running a 10 A/F...why the heck would you do that? Too rich is not good. Sounds like you cracked a ring landing, i guess we will find out. In the future run in the mid 12s A/F.

If the timing was being retarded 1-2 degrees, 20%, that means you were getting a significant amount of knock. I don't know this ECU specifically but most of them use a basic algorithm. Example, 1-3 counts of knock = keep advancing timing, 4-6 counts of knock = keep timing where it is, 7+ counts of knock = start retarding.

You never hit full load in 1st and 2nd gear which is why you didn't see these signs until 3rd gear.

Are you tuning this on the fly? What software are you using?

Quickvr4

Too little timing is not good either as your EGTs will go through the roof.

What were your readings for:
EGTs
IDCs

Is cylinder 8 furthest from the feed on the rail?

Do you have a datalog that you can show us?

I really think that methanol is a must when running boost on these N/A engines and especially if you are going to beat the crap out of it and not use race gas.

GT-ER

Yes, EGT will be higher, and it may have been a contributing factor, but when it blew I was just getting on it ( short run ).
High EGT's will kill in loooong pulls. IDC was below 80%.

Mid 12's A/F ratio? You must be confused with naturally aspirated engine. I was running high 10's ( sometimes touching low 11's ) which ultra safe.

Bosch ECU's are ULTRA sensitive and can retard well over 10* of timing if they have to. Even bone stock most of these vehicles can see 3-4* of timing retard easily. My previous GTI 1.8T ( similar bosch ECU ) ran with 5-6* of timing retard constantly in every gear and in 40K miles never blew anything with over 400whp.

Granted, seeing 0* across the board will be safer no doubt, but when the C55 broke it was in a short 2nd gear burst with 0* of retardation. Again, this is on a 105K mile engine that saw lots of nitrous before seeing boost....maybe it was just time.

Considering that the MP112 supercharger kleemann uses may barely do more than 430-450whp at most, I doubt the oem E55 setup will have any issues. My E55 has had over 500+whp for over a year with zero issues.

Keep in mind, the compression will be dropped from 11.1 to 9.0.

betrezra

Hate to see that.

did you get any dyno data or 1/4 mile runs before it blew with the smaller pulley?

who did the new tune for the smaller pulley?

GL.

GT-ER

No data... Jerry would tune my ECU as per my request ( I would just ask him what I wanted and he would do it ).

benzmodz

What about some upgrades to a higher output fuel pump and bigger injectors and so on.

GT-ER

He has 440cc injectors and the oem fuel pump has kept up with pressure so for now all is good.

Velociabstract

It appears your going to busy on your days off. Just don't make his car too fast.

Les

91RS

He's had no problems with the bigger injectors? Cory had told me something about a spot in the RPM range that wouldn't cooperate or something like that, which is why they now use the secondary fuel pump with stock injectors setup my kit uses.

Are you going to be doing the pistons yourself?

GT-ER

Hot starts seem to be the biggest issue, can't get it to start easy when warm. Part throttle and full throttle were fine. Long term fuel trims weren't too happy either but the car has a cel for 100 other thing so it's no biggie...lol.

Yes, I'll likely be doing the piston install.


Days off? Try a little every day before going to work. LOL.

91RS

Hmm, that's interesting. You might want to change that fuel system, might help the overall performance.

Any chance of maybe a how to how replacing the pistons and rods? Are you leaving the engine in the car or taking it out?

dre5373

This would be awesome!

Wasn't Blackbenzz runing a stock bottom end in his 700+rwhp monster CLK? Makes me wonder if it was the nitrous...

Just out of curiousity, did you check the compresion when your friend was having the issues when he was still N/A?

Robert AMG

iTrader: (1)

With those lower timing i pray you don't have a melted piston or/and melted cylinder wall(do you know also what was AIT?) , the heads are little different the 55K has heads with higher volume, so with 55K pistons and rods you will have higher then 9:1 compression ratio, we don't how much higher cause there is no data available about heads volumes but i think below 10-9.5.

91RS

I thought the heads were different. I think Cory told me the gaskets were the same though.

GT-ER

I'll likely take the engine out. Maybe I'll take pics.

blackbenzz had lower compression than we have.

Never took compression before on this car.

Didn't know that. Lower is lower however. 7-9* of timing, while low, isn't exactly meltdown low and I never did any high speed pulls ( never went over 115mph ) so I doubt it was a big deal. Plus, the car still has 90+psi of compression and both plugs were fine when removed which means the damage shouldn't be THAT bad. Guess I'll find out.

Robert AMG

iTrader: (1)

you're right.
after all it's time for 55k piston and rods.

GT-ER

Yep...hopefully it will be a beast when it comes out.

Quickvr4

GT-ER, I have not tuned a car in a long time, 6-7 years. We used to tune a lot of mid 90's japanese turbo cars and aim for 12:0-12:3 A/Fs and maybe closer to redline high 11s. Is this rich tune due to the engine being N/A? I am not sure how that will affect it.

I am really curious to see what this piston looks like.

Did you do a leak down test? Maybe the issue is in the cylinder head...? Are these heads aluminium?

GT-ER

I've tuned in the 12's using race gas but rarely go that high on pump gas, too risky. High 10's is kind of the other extreme but since it's not my car I tried to be conservative...which apparently was useless...lol.

I didn't do a leakdown test since I figured I may as well go the extra mile regardless since removal of the cylinderhead is already complicated enough. May as well remove both along with the oil pan and do the whole thing. Even if it turns out to be a valve issue I'll still build a stronger engine.

They are made of aluminum.

91RS

Where were you reading your timing readings from? I just checked mine with a hand held universal scanner that shows live data, and it shows timing advance. I'm not an expert on what this should be yet though. Normally driving around it was -25* or so and under WO it was -7* the first time and -8* the second time. The MAP sensor was showing around 9 inches at idle which is about 4.4psi and at WOT it was around 25 inches which is about 12psi. Is that right? It can't be reading boost because there's no way there's boost at idle!