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View Full Version : Acceleration movie from 30-200 km/h with new engine and 1.75


Wolf66
16-02-07, 16:17
I finally found time to write new chip. Car goes wery well with it. Acceleration time from 100-200 km/h is 7.8 s. Here is some info of other cars fo comparison:


http://www.moj-album.com/slike/5884310/CdJ_4yAD9edBJAnp.jpg





Movie: http://www.mobisux.com/album/data/500/4285230_200.avi


Graph from datalogger:



http://wolf66.moj-album.com/slike/5884310/IQ9Avamb8ZW_xsrZ.jpg


100 km/h: 12.78 s
200 km/h: 20.56 s

100-200 km/h: 7.78 s


Boost is now limited to 1.75 bar. Next step is 2.0 bar. 8)
j1v
17-02-07, 18:11
Very impressive.
What have you done to turn it to 8k rpm ?
I'm very inpatient to see my runs like this. I'm afraid how ever to run it over 7k, even I have forged internals - still don't know about the reliability of the valvetrain.

And one more thing - isn't 12.5 AFR on 1.75boost and 8k rpms pretty risky? I would run a car like this no leaner that 12
Wolf66
17-02-07, 19:26
I have gasflowed head and colombo&bariani street max cams and engine revs happily to 7800 RPM.

I found out that AFR of 12.5 produces highest power with 100 octane gasoline. Ignition advance is crucial factor, but i'm constantly logging engine parameters, including knock sensor and there is no detonation.
j1v
17-02-07, 19:43
are those 7800 on stock valve springs ?

It is normal to have most power at 12.5-13, but is it safe enough ?
I would sacrifice a couple of ponys and go on the safe side. In my opinion knock sensor data is not that reliable, especially on a rebuilt engine with custom cams.
Wolf66
17-02-07, 21:19
Yes, i have stock valve springs.

With my old engine, which had all stock internals except tipo inlet cam and oem inlet as exhaust cam i made 60 000 km with 1.5 bar boost at 7000 RPM and 12.5 AFR without any problems. I sold that engine and it runs still. You can see the video of acceleration with that engine in my other post.

I made 3000 km with new engine and i don't have any problems either.

People loose power with too rich mixture and incorrect ignition advance. If you have to much ignition advance, you have to add fuel to combat knock and higher temperatures that it produces. Richer mixture is burning slower so you acomplish the same thing as with leaner mixture and less ignition advance, but you loose power because mixture don't burn so well.

I'm logging aditional knock sensor not the oem one.
j1v
17-02-07, 21:39
I agree on everything you've said, my thought was even one tank of bad fuel (not real 100 octane) on this kind of setup could make a lot of problems. But maybe in Slovenia you do not have those problems with gasoline we have ;-)

What kind of knock monitor are you using ?
Wolf66
17-02-07, 22:25
You are right, if the quality of fuel varies a lot, it is better to stay on the safe side. As i said i didn't have any problems yet, but i'm always using the same fuel from the same company (OMV). We'll see, when i raise the boost to 2 bar. :D


I use additional knock sensor, which has external 5v power supply and it signals knock as variation of that supply voltage. It is not perfect, but it gives good indication if sustained knocking occur. Oem Q4 sensor is producing around 0.2 volts and more when knock occurs, but it is highly inaccurate because of voltage variation and because at high RPM this 0.2 volts are produced by valvetrain.
T M Oren
19-02-07, 19:14
Do you have pictures of your engine?
During rebilding?
djsly
20-02-07, 05:55
take a look here: http://www.berlinasportivo.com/phpBB2/viewtopic.php?t=180
Juan AR155Q4
20-02-07, 14:20
Wolf, what an engine you have done!!!

Are you running your GT30? Hows lag and spool?

PS: Again, congratulations.
T M Oren
20-02-07, 14:53
Are you uesing standard transmision?
Wolf66
20-02-07, 16:07
Thank you.
I don't have GT30 yet. Currently i'm using Holset H1E which has a lot of lag.
I'm using standard transmission, apart from clutch and lightened flywheel.
T M Oren
20-02-07, 19:05
Okey.
Were do you by parts?
Wolf66
21-02-07, 07:30
Okey.
Were do you by parts?

Mostly in Italy.
Brul(tm)
21-02-07, 17:09
Mostly in Italy.

on ebay, webshop or do you have any special contacts?
I think I must decide what to do with my engine soon. So a complete rebuild with different parts is a very good option.
Your setup sounds very interesting ;) But I also see some challanges....

Greetings,
Marc
Wolf66
21-02-07, 22:05
There are some shop near the Slovenian border which can deliver tuning parts. If you want to buy parts online, check www.protoxide.it. They are a little bit more expensive, but they have all you need.
Brul(tm)
22-02-07, 19:09
I think I must decide what to do with my engine soon.

I am afraid the engine made the desision for me tonight :cry: :cry: :cry:
Not sure what has happend. Engine runs "normal" only the knocking sound from the head :shock:

Greetings,
Marc
AlfaJack
22-02-07, 22:07
I think I must decide what to do with my engine soon.

I am afraid the engine made the desision for me tonight :cry: :cry: :cry:
Not sure what has happend. Engine runs "normal" only the knocking sound from the head :shock:

Greetings,
Marc

Oh dear, sorry to hear this Brul :(
sub555
23-02-07, 18:59
sorry to hear that mate :cry: :cry: :cry: :cry:
pitucas
23-08-07, 21:57
This post is ancient...

What has happened to your engine, Brul???
Brul(tm)
07-10-07, 22:41
This post is ancient...

What has happened to your engine, Brul???


A bit late maybe, but the engine is fine :cool:. The problem was the clearance of the valves :eek: That was twice the number allowed :eek::doh: So replacing some valve plates and everything was fine again :smile:

Greetings,
Marc
AlfaJack
08-10-07, 10:01
Nice one Marc :)

Not seen you about for a bit Marc, welcome back :D
Brul(tm)
08-10-07, 16:33
Not seen you about for a bit Marc, welcome back :D

Was busy busy busy :rolleyes:

But the Q is not in a good condition at the moment :frown:
The turbo is gone, the turbine on the exhaust side is stuck in it's housing..... So i am waiting for a used turbo at the moment.

The stands like this in my garage....
http://i115.photobucket.com/albums/n288/BrulTM/Alfa%20155%20Q4%20repair/IMG_5766.jpg
http://i115.photobucket.com/albums/n288/BrulTM/Alfa%20155%20Q4%20repair/IMG_5768.jpg


The exhaust gasket is gone
http://i115.photobucket.com/albums/n288/BrulTM/Alfa%20155%20Q4%20repair/IMG_5772.jpg

The cause of all my problems
http://i115.photobucket.com/albums/n288/BrulTM/Alfa%20155%20Q4%20repair/IMG_5771.jpg
http://i115.photobucket.com/albums/n288/BrulTM/Alfa%20155%20Q4%20repair/IMG_5774.jpg
Made it till 283.926km :eek: Engine is fine, so after replacement the counting continues ;)

I am sorry for the topic pollution :tapedshut:

Greetings,
Marc