Engine problems...

[Devils speedshop]

Hey all

I have a big problem with my new engine.

I have been on the dyno 2 times now and havent found whats wrong yet.

The problem is when we run it on the dyno we get a ok curve up to around 5000 rpm where it hits its max og 260 hp and 350 nm and the it all stops and the curve starts to go down again, the engine is build for 8800 rpm and should give 357 hp and 340 nm.

But does anyone have some sugestions?

The ign. Is set at 30 deg. Befor top as it should be. And no clutch or wheel spin on the dyno.

And the dyno from US says 260 hp at 5000 rpm so thats ok but then it stops....insted of going up.

There is nothing wrong with the cam, the valve adjustment is 0, lambda 0,85 /12,5 AF, and the ignition does not die, or does it.. Dont know wht happens after 5000 rpm.

One other ishue is that the distrupter where supose to be set at 30 deg befor top, but when i tryed to start up the engine for the first time it whould not start at all we tryed to adjust the timing at it  started up. But if the setup from the US it set back its 30 deg after top befor the trigger hits the magnet, and i can't see how this chould run at all...

I can post all the pic if you can just help me.

Christian Ulberg

[Frallan]

Electronics

Try another distributor or simply replace the distributor (the more simple, the better for this testing) with something else that is proven and works.
Just to see that you are on the right track, a stock distributor with a performanec coil would or should bring you past 5000 rpm.

Of course it can  be a lot more but this is the first and most simple step check as my conclusion of what information I have being far away.

Afterthought, you are not having a sparkplug wire damaged in some place and it jumping to earth. That could cause something like this. Not visible in daylight and tricky to find.
Or a plug wire being too close to the trigger wire.....it will disturb the trigger signal and ....not good.

[BeetleBug]

Oh man... Not you too. 2012 got to be the year of ignition issues. Recently we have heard about several engines here in Norway with similar issues as you. They rev up to a certain point then dies. All of them fixed their problems by changing distributor. But, I take it for granted that you have the best of the best Made In US ignition system? Do you dyno the engine in the car? Do you have enough spark? Plug gap? And most importantly, what do the engine builder say?

BB

[Devils speedshop]

Im goner try to get a new distributor and try that sounds like a good idea.

Yes the engine is in the car.

Sparkplug gap the same as from the us 0,75 mm

I don't know who to check if there is enought spark, but im running a MSD AL7 box with a pro power coil, and the new distributor from CB Performance.

No help there... ( It ran in the dyno in the US)

[richie]

Is it the programable CB distributor? have you checked the timing at above 5000rpm to see if it changes up there?  do you have any video of it on the dyno in denmark? it might help to actually here the engine as it gets to 5000rpm.

How steeply does the power fall off,do you have the dyno printout we could see?  what afr did Pat set it up with? are you using the same fuel that it was dynoed with in the states? the same brand and octane?

Good luck getting it sorted

cheers richie 

[Tekken]

Hi Christian.

Sorry to hear this.When are you supposed to have 30 btdc? When you start/idle you should have a lot less.Do you know the advance curve on your distributor?A digital timing light with retard/advance function would help you to find the advance when running the engine.

What is your battery voltage?

[bang]

Lock the dist and set at 26 deg. Fixed it always work for me.

[Devils speedshop]

No its a normal distributor like a MSD.

I forgot the papers at the dyno guy, where a bit down after 2 failur on the dyno.

But after 5000 rpm the curve went slowly down if we have keept going to 8800 rpm my guiss 210-220 hp..

Pat said he ran the engine 12,5 AF so the same in the safe zone.

We are not using the same fuel it ran on vp-c14 im running on Sunoco Maximal 116 oct. so it should be the same there..

I adjusted it with a timing gun at 30 dtdc. Its adjustet to the 30 deg when the engine is pass 4500-5000 rpm so the retard is max.

Im running 16v battery, and i had a charger on it who can deliver 25 amp.

[RMS Boxer Service]

How does the engine sound above 5500 rpm?? Just down on power or is it coughing
or cutting out like a rev limiter??  Try to measure the voltage at the big red wire at
the MSD box.  Did the engine run a MSD 7 box when dynoed??  Maybe a bad coil?

Lots of questions but I was just brain storming....


/Rolf

[Udo]

No its a normal distributor like a MSD.

I forgot the papers at the dyno guy, where a bit down after 2 failur on the dyno.

But after 5000 rpm the curve went slowly down if we have keept going to 8800 rpm my guiss 210-220 hp..

Pat said he ran the engine 12,5 AF so the same in the safe zone.

We are not using the same fuel it ran on vp-c14 im running on Sunoco Maximal 116 oct. so it should be the same there..

I adjusted it with a timing gun at 30 dtdc. Its adjustet to the 30 deg when the engine is pass 4500-5000 rpm so the retard is max.

Im running 16v battery, and i had a charger on it who can deliver 25 amp.

Sounds not good. sunoco fuel need bigger jets that is for shure, but if the afr is ok it should work. i would try an msd distributor for testing. good luck and i hope you can race at vandel

[Devils speedshop]

The engine sounds ok, its just not making any power.

So there are no cutting of the ign.

No i havent try to meassur how much but sins i a 16v charger that delivers 25 amp and the altenator is a 55 amp there should be no problems there.

Yes it tan with the al7-2 box

Christian Ulberg

[RMS Boxer Service]

The engine sounds ok, its just not making any power.

So there are no cutting of the ign.

No i havent try to meassur how much but sins i a 16v charger that delivers 25 amp and the altenator is a 55 amp there should be no problems there.

Yes it tan with the al7-2 box

Christian Ulberg

The charger "could" be the problem as it could make much electical noise. Most automotive chargers have a high ripple on the output, like changing from 14-16 volt
(2 volt ripple) at 100 hz frequenz.

Ripple voltage looks like the lower curve in this image:


If it's a switch mode charger strange things will happen if it is connected to other devices with high voltage discarged or oprating at high frequenz.
All these things are present in a MSD ignition system. I have seen industrial switch mode power supplies go totally cracy and altering the voltage
up and down vigorously just because they where connected to another very small switch mode supply. Voltage vent from 24 volts  well over 60 volts  

 Disconnect the charger completly during the time the engine is running to ensure that electrial noise or wrong voltage or ruled out  Move the coil to
another location to avoid electrical noise on the trigger sensor/wiring.


Just my 2 cent.

/Rolf

[Udo]

If the ignition works i would try bigger main jets for testing . If your car (fuelsystem) can handle it

Udo

[Devils speedshop]

I don't belive that it need fuel, the lamdba is perfeckt, my fuel system can deliver 460 gallon/hour so no problem there.

[BeetleBug]

If the AF is spot on and similar to what it was when it was dyno`d in the US I can't see how your problems can be fuel related. The way I read this it sounds like it is dropping of approx where it is supposed to build cylinder pressure and power. You are also saying that it has more torque at 5000 rpms compared to what it had when it was on the dyno in the US and max torque is achieved at max BMEP.

We all know that a engine need:

- Fuel
- Air
- Compression
- Ignition

You know that the air and fuel is ok and I take it for granted that the leak down is also ok considering that it makes 260hp at 5000. Perhaps stupid but I ask anyway, did you try so separate the plug wires? Have you also tried to loose the spark plug boot end a bit from the plug to increase the spark? And do you use a similar ignition system that was used in the US? 

Good luck Christian!!

[Erlend / bug66]

My new engine did not work properly with the ignition system I used to have. I had a pertronix billet distributor and a Pertronix coil. The timing would not be static!

We tried a 009 with a blue coil. Nada ignition even with old school points and condensator.

Got a full MSD kit. and the timing now move maybe 0,5degrees... It's spot on up to 9K rpm!


Could you check with an entire new or other ignitionset?

[Devils speedshop]

I did not try to separate the wires, can try..

Why does it increase the spark on the plugs if the are loos on the top boot?

Yes it ran in the US with a MSD 7AL-2 box too.

Here is what ill try: put a 12 std battery in the car. and make sure that all wires are not laying on top of each other to keep down the noise.

1: Change it to a MSD Distributor and see if any change

2: Try another ignition box, have a 6al box

3: Another coli.

[Erlend / bug66]

And do it one step at a time if you want to find the non-working part, or change thhe whole system if you are fed up, and want it to work 

I did the later

[Devils speedshop]

yes ofcourse one of time, don't want to spend extra money on something that arnt neasseay.

[Erlend / bug66]

hehe. We did 2 different approaches then 

[Udo]

Change it to a MSD Distributor and see if any change

2: Try another ignition box, have a 6al box

This is the best way to see if there is nothing wrong with the ignition . But changing the jets for one pull is not much work 
When i switched from vp14+ to sunoco premium my engine was too lean ... My engine now is running with shell pump gas
Udo

[Devils speedshop]

Its because of the jetting im on the dyne because there is a big diffrence from the us and here. My old engine startede on 180 hp with the jetting that gave it 285 hp at Roger Crawford, and i enden up with 298 hp just by jetting it right.

Christian Ulberg

[cassa]

I don't belive that it need fuel, the lamdba is perfeckt, my fuel system can deliver 460 gallon/hour so no problem there.

There is no sutch thing as a perfekt lambda.

[K-Roc]

I would not be trusting what a  $100 02 sensor tells you to tune an engine this expensive.

Start by pulling your plugs and reading them after a dyno run.

Remember you tune by giving an engine what it wants... not what you think it needs....

K-Roc,

[Udo]

Its because of the jetting im on the dyne because there is a big diffrence from the us and here. My old engine startede on 180 hp with the jetting that gave it 285 hp at Roger Crawford, and i enden up with 298 hp just by jetting it right.

Christian Ulberg

Because of this and the different fuel i would try some bigger main jets . In california the engines breath a lot of smok

Udo

[Devils speedshop]

I rather put my trust in the lamda value and the dyno chart, for me what you say about just looking at the sparkplugs, is like more a guiss the real data.

If you can't trust the o2 sensor there are alot of cars in the world that have a big problem....

We already did a few sizes up jetting, but as long as it does not work above 5000 we can't finaly say how big we have to try a few times on the dyno.

But ill try and change the distributor and make sure the wiring dose not get in contact with and noise cabels, think there might be noise that disturbe, from what i can read it look like a problem on my car.

Christian Ulberg

[Torben Alstrup]

A signal wire is too close to a power line. - Electric noise to the box.
T

[K-Roc]

If you can't trust the o2 sensor there are alot of cars in the world that have a big problem....

Leaded race fuel can ruin an 02 sensor very quickly............

[dangerous]

There is some very good advice above.

To clarify(perhaps) what K-roc is saying, use the sensor as a 'tool' and not gospel.
...especially if it is covered with leaded fuel deposits.

You can also use the plugs(get a magnifyer) and also
the hp chart as a tool also,
just as you are already doing.

The odd component in this equation is the fuel, so i would focus on that.
The A/F that it will want is NOT 12.5, it will be the number that produces the best power.
The optimum A/F will likely vary with rpm, let alone different engines, fuels and fuel delivery.

My instinct is that you can add some fuel, and also pull out some timing above 5000.
For example, my engine recently picked up 9hp at 8000 by backing the timing down from 28 to 24.(programable)

[Udo]

The A/F that it will want is NOT 12.5, it will be the number that produces the best power.


That is right, most engines have the best hp with different a/f ratios

Good luck Christian