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Discussion Starter · #1 ·
My brother just picked up a beautiful 1999 SL600. He gave a ride and the smooth power of the V12 is impressive. He knows that next Friday I'm picking my car up after it's engine rebuild. With the rebuild we've bored it .060 over (now it's closer to a 3.7), forged JE pistons, euro cam gears, ported and polished head, balanced, all new 1mm bigger stainless steel valves, and I'm hoping for 360hp. My brother asked me to stop by his place so we could go for a little race. I'm curious myself. His car weights around 4400lbs. and it's an automatic. I think that I'll pull a couple of car lengths on him.

Greg S.
 

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Gerg said:
My brother just picked up a beautiful 1999 SL600. He gave a ride and the smooth power of the V12 is impressive. He knows that next Friday I'm picking my car up after it's engine rebuild. With the rebuild we've bored it .060 over (now it's closer to a 3.7), forged JE pistons, euro cam gears, ported and polished head, balanced, all new 1mm bigger stainless steel valves, and I'm hoping for 360hp. My brother asked me to stop by his place so we could go for a little race. I'm curious myself. His car weights around 4400lbs. and it's an automatic. I think that I'll pull a couple of car lengths on him.

Greg S.
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hi Greg

A bit unsure about this - the SL600 is going to have a huge amount of torque.
But it also weighs two ton! So go for it - really hope you win.

Interesting mods to the engine by the way....do you need to remap it now or will the original chip be able to do its magic on these alterations? Will the porting and polishing add any power?
 

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hold your HORSES, Greg :nono:
as all know I am NOT the technical mastermind in this forum ??????
but even with my limited knowledge of engine-techniques I wud HIGHLY
recommend TO WAIT with any kind of RACE until your -newly rebuilt-
engine is run in, it shud be ran in -in the same way as a brand new engine- I wud assume -
(unless of course, you are ready for a new rebuilt very soon again) :M5rev: :typing:
 

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Discussion Starter · #4 ·
Jahangeer,

I had a Dinan chip in my car before the rebuild. It was tuned to the cam gears so I'm pretty sure it'll be OK. As for the port and polish, it will give marginal hp but it'll really improve throttle response. The reason we went .060 over on the bore was the previous owner went .050 when he rebuilt the engine.

M5touring reg,

I've asked the mechanic to drive my car the first 200 miles after the rebuild. Then after I pick my car up I'll have another 200 miles until I get to my brothers. I'll ask the engine builder if 400 miles will be too soon for little race.

Greg S.
 

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Gerg said:
Jahangeer,

As for the port and polish, it will give marginal hp but it'll really improve throttle response.

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Sounds like you have an excellent motor now Gerg
so it improves throttle response - mmm. I have been tinkering with the idea for a while.....
 

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Jahangeer said:
Gerg said:
Jahangeer,

As for the port and polish, it will give marginal hp but it'll really improve throttle response.

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Sounds like you have an excellent motor now Gerg
so it improves throttle response - mmm. I have been tinkering with the idea for a while.....
I'd personally put 1K on an engine before i'd give it this sort of treatment.
 

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I would certainly give that motor more than 400 miles to seat everything before giving in to a race. I recently had an experience with one of those 600's where he came up behind me at about 100 MPH flashed me and then was gone.
 

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I recently rebuilt my 3.6 litre. I did 1500 Kilometres on it before I took it above 5000rpm, the majority was no more than 4000rpm. You need to make sure the engine travels across the entire range of rpm with particular attention paid to putting the motor under strain at low rpm. Travelling up hill in 4th at a lower speed achieves this.

400 miles + Race = Rebuild.
 

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Discussion Starter · #9 ·
Ok, OK it was a terrrible idea ouich Thanks for bringing back down to reality.

Greg S.
 

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i honestly don't care which is really faster. i love the M5 much more than any Mercedes Benz - old or new. i would take the M5 any day of the week.

and if i lost to one of those MBs, then it still wouldn't matter because of the V12 vs I6 issue.
 

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Discussion Starter · #11 ·
My engine now has 5,000 miles on it. I gave my brother in law a ride over the weekend. After a few spirited starts on some country roads he declined a race. He went home and got online and started looking for mods. His wife even asked if we raced and he said not until he does some work to his V12 :confused3 . I embarrased him without even racing. His car does weigh 600 pounds more than mine so that would have been a big advantage from a standing start.


Greg S.
 

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Gerg said:
My engine now has 5,000 miles on it. I gave my brother in law a ride over the weekend. After a few spirited starts on some country roads he declined a race. He went home and got online and started looking for mods. His wife even asked if we raced and he said not until he does some work to his V12 :confused3 . I embarrased him without even racing. His car does weigh 600 pounds more than mine so that would have been a big advantage from a standing start.


Greg S.
------------nice one - you put the fear of the "M" in him!! :7: :7:
 

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I can verify Greg's car is fearsome. :M5launch:
 

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The SL600 is a heavy beast, good looking car but way too heavy up front. A friend took his SL600 to a trackday once and was very disappointed with the way the car behaved - heavy and with way too much understeer to be competitive/fun.

When the car does shine is when driven in a straight line, so watch out... :M5launch:
 
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