Porting, Polishing, and Cams project
I'm very nervous about the whole project and almost cancelled my appointment numerous times.
I do have an appointment this weekend and MB is installing a new fuel filter so I can do one more Dyno pull before my baby gets "chopped" up. For those of you who have followed my various projects, you will know that my last Dyno run showed that the car isn't getting enough fuel and A/F ratios are a tad high. Speaking with Renntech assured me that the map used for my car should have the A/F ratio running between 12 – 12.5. It is assumed that I either have an air leak, or low fuel pressure / flow. The air leak has been ruled out, and fuel pressure tested fine at low-mid RPMs. I was told that our fuel pumps will raise pressure even with a semi-clogged filter, so that is what I’m taking care of Saturday.
I’m going to ask MB and PE to take some pictures along the way.
My question to you all is…Should I do anything else while the car is apart?
The ECU is going back to Renntech for another adjustment and the SS exhaust piping will get finished as well.
I'm very nervous about the whole project and almost cancelled my appointment numerous times.
I do have an appointment this weekend and MB is installing a new fuel filter so I can do one more Dyno pull before my baby gets "chopped" up. For those of you who have followed my various projects, you will know that my last Dyno run showed that the car isn't getting enough fuel and A/F ratios are a tad high. Speaking with Renntech assured me that the map used for my car should have the A/F ratio running between 12 – 12.5. It is assumed that I either have an air leak, or low fuel pressure / flow. The air leak has been ruled out, and fuel pressure tested fine at low-mid RPMs. I was told that our fuel pumps will raise pressure even with a semi-clogged filter, so that is what I’m taking care of Saturday.
I’m going to ask MB and PE to take some pictures along the way.
My question to you all is…Should I do anything else while the car is apart?
The ECU is going back to Renntech for another adjustment and the SS exhaust piping will get finished as well.
1. See if ANYONE makes, or call some manufactures like Manley, UNDERCUT valves. That is, they cut away some material right at the head of the valve. This alone can often improve flow by about 15%. These are sometimes refered to a TULIP valves.
2. When you change cams, make sure that the new lift/duration will work with the stock valve springs. Otherwise they could float. A condition you DO NOT want, trust me. Depending on the cam profile you may have to change the springs ie increase the spring rate.
3. Look carefully at the intercooler. I have never had my hands on one, so I am just using past knowledge/experience here on other brands. Check carefully at the ports, and ANY casting marks left over. A SMALL improvement could be made here by cleaning them up. It won't make a BIG difference, however every little bit helps.
Sounds like you should have one KILLER AMG when your done.
Keep us posted and GOOD LUCK
PS: I blow a head gasket on my blown stang becsue of an aging fuel pump. It dropped pressure/flow, a little spark rattle later, and ONE GIANT CHOCOLATE MILKSHAKE.
See yeah
Want to take it for a drive??
1. See if ANYONE makes, or call some manufactures like Manley, UNDERCUT valves. That is, they cut away some material right at the head of the valve. This alone can often improve flow by about 15%. These are sometimes refered to a TULIP valves.
2. When you change cams, make sure that the new lift/duration will work with the stock valve springs. Otherwise they could float. A condition you DO NOT want, trust me. Depending on the cam profile you may have to change the springs ie increase the spring rate.
3. Look carefully at the intercooler. I have never had my hands on one, so I am just using past knowledge/experience here on other brands. Check carefully at the ports, and ANY casting marks left over. A SMALL improvement could be made here by cleaning them up. It won't make a BIG difference, however every little bit helps.
Sounds like you should have one KILLER AMG when your done.
Keep us posted and GOOD LUCK
PS: I blow a head gasket on my blown stang becsue of an aging fuel pump. It dropped pressure/flow, a little spark rattle later, and ONE GIANT CHOCOLATE MILKSHAKE.
See yeah

i will be interested to see if Renntech can get the tuning right on the car...this is the main thing that worries me
Since the map on our car is dynamic for the most part, I don't think additional tuning will be required if you already have a stage II ecu.
Keep your fingers crossed!
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Since the map on our car is dynamic for the most part, I don't think additional tuning will be required if you already have a stage II ecu.
Keep your fingers crossed!
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Here's the ? of the day. What could cause my A/F ratio to be off?
I installed the phenolic spacers myself, so I could have #$%$#% something up.
I doubt it's the tuning, but the ECU is going back just to be sure.
Fuel pressure / flow?
Anything ignition related? Could something be advancing the timing and making the car want more fuel?
Air / Vacuum leak?
I'm pulling these out of my a$$, but you guys are the gurus....
Last edited by sales@eurocharged.com; Mar 28, 2007 at 03:46 PM.

Here's the ? of the day. What could cause my A/F ratio to be off?
I installed the phenolic spacers myself, so I could have #$%$#% something up.
I doubt it's the tuning, but the ECU is going back just to be sure.
Fuel pressure / flow?
Anything ignition related? Could something be advancing the timing and making the car want more fuel?
Air / Vacuum leak?
I'm pulling these out of my a$$, but you guys are the gurus....
Wouldn't a leak after the blower make your AFR decrease not increase? I doube it is a leak problem, it's gotta be fuel.
Sorry, I wish I knew more.
Yup, but after the conversation I had with Renntech, I'm not sure if they will be able to do anything for me. He has assured me that the map would not make the car run above 12.5. I got the specs for the cams printed out and I'm going to see if he or the guy in Germany that makes the maps needs to do anything.
BTW - I called Kleemann to get the specs for their cams and ended up in an email conversation with Rick Sande, and he said "Sorry Jerry we don't give out the specs for our cams"
LOL - I replied with "Then I can't properly tune my car....too bad."
Kleemann's way of strong arming you into their ECU.
BTW - I called Kleemann to get the specs for their cams and ended up in an email conversation with Rick Sande, and he said "Sorry Jerry we don't give out the specs for our cams"
LOL - I replied with "Then I can't properly tune my car....too bad."
Kleemann's way of strong arming you into their ECU.
To do an honest check you will need to install a wide and O2 sensor right into the exhaust and install a gauge inside the car. Innovate has fantastic products for all ranges of budgets.
After having the gauge and the sniffer installed we went out and logged some data only to find that the car was running 100% spot on just as RENNtech said it should be. The car was with - in .2 at every point in the rev band with what RENNtech said their ECU should create.
So the moral of the story is make sure your readings are accurate before you get worried and have the car checked out. We were just like you and about to change the fuel pump etc just to make sure it was fine. The gauge was the only way to really know for a dnyo could be out of tune fairly easily.
Good luck
Last edited by CynCarvin32; Mar 29, 2007 at 12:17 PM.
To do an honest check you will need to install a wide and O2 sensor right into the exhaust and install a gauge inside the car. Innovate has fantastic products for all ranges of budgets.
After having the gauge and the sniffer installed we went out and logged some data only to find that the car was running 100% spot on just as RENNtech said it should be. The car was with - in .2 at every point in the rev band with what RENNtech said their ECU should create.
So the moral of the story is make sure your readings are accurate before you get worried and have the car checked out. We were just like you and about to change the fuel pump etc just to make sure it was fine. The gauge was the only way to really know for a dnyo could be out of tune fairly easily.
Good luck
i agree...but i was thinking that Jerry had a WB02 sensor in the car...if not, you need to get one and put it in your car...
I have decided to drop the car off tomorrow instead of early next week. If MB can have the head off by Monday afternoon, then I'm almost certain I will have the car back before the meet.








