soulsearcher

When its all said and done, the "games" played with the dyno numbers can certainly be manipulated but 1/4 speed is a function of HP. Granted, ETs are very dependent on traction and launching skills but speed I have found is a true measure of HP, especially if you keep track of the Density Altitude (DA).

Anyway, just as I suspected there was no real change in my speed after installing the VRP825 kit.

Before the VRP825 kit and Victors so-so tune, I had a renntech ECU/TCU flash and ran 119.5 mph (DA-1100). Yesterday, I did 120 mph (DA 1005***). I will say that Marcins intercoolers did eliminate heat soak (I did 9 runs, all same speed). Before the kit, I could not do that.

One thing I forgot to mention about Motorwerks in Detroit was that after the Texas Mile, I had to replace several panels under the car (They came off partially). Since then my tech found many panels that were not re-installed correctly and many missing sheet metal type screws that were never re-installed back by Motorwerks techs. Poor attention to detail. Just stating my experience.

ET: 11.95 With MT ET 305/35/18s @16-18 psi
60: 2.0
330: 5.3
1/8: 7.9
mph: 93.7
1000:10.2


ET: 12.9 With Falken 305/25/20 @38 psi
ET: 12.7 = @22 psi


***B/P 29.7, 96% humidity, 68 Temp.

RenntechE55

Wait your car ran a 12.7 with DR's and a VRP 825 kit?

JAYCL600

JC call me this week

Thericker

I really think your application would benefit from a Custom Dyno tune from Powerchip-Jeremy (call or pm me, I have all contact #'s you need to get this going)

320 dreamer

nows a great time to sign up for eurocharged tuning session in atlanta on 12/12. tony can custom dyno tune your car and get those numbers were they should be!!

https://mbworld.org/forums/sl55-amg-...uning-day.html

soulsearcher

RenntechE55.....Sorry about that. Meant 12.7 with Falkens @ 22psi.

JAYCL600......Have a looong trip this week. I get to test "drive" my brand new 24 foot v-nose race trailer and guess whats in it! Call u on the road.

Thericker......Victor was suppose to do a custom tune but long story short, it did not happen n I ended up with a box tune.

320 Dreamer.....I'll be there to meet everybody but without my car. The car will be out-of-state getting a "special treat".

Benz-O-Rama

To put your mph in some perspective, my bone stock SL600 with only a Eurocharged shelf tune, turned a max of 121mph.

jmf003

I agree with the other guys that it looks like the tune is holding you back.

You did pick up some trap speed (120 mph with +1000 DA compared to 119.5 MPH with -1000 DA) but your setup should be faster than that.

The most noticeable thing with your ET is the 60' time. It's pretty remarkable that you run a sub-12 1/4 with a 2.0s 60' time. All the R230s with low to mid 11 second 1/4 miles have 60' times in the 1.6s to 1.7s range.

Good luck!

ITAVMT

Does the VRP825 kit come with a tune?

soulsearcher

I agree with all the remarks. The verdict is still out as to whether the tune is the culprit. The tune was identical (supposedly) to the ones that went into the other V12TT VRP cars.
The three other possible issues still on the table are:
1. MAP sensor
2. Wastegate
3. Blow off valve

Dyno graph shows boost never gets above 17.5 if I recall correctly. Should be up to 23-24 based on tuner.
Also boost peaks at 3600 rpm and then drops off significantly.
While rare, mercedes does have a tech bulletin that talks about miscalibrated/malfunctioning turbo pressure control valves.

MarkoCL65

The kit makes 825 HP on a 65 engine. I'm not sure why this hasn't been explained. It should and will make less on a 600 engine. I believe the 600 engines will be well north of 750 HP once the tune is figured out.

Gondon

I thought the S65 and S600 engine only difference was that there is more boost?

Lexani

65s have a higher displacement.

V12Godspeed

+1, Even though the extra 100 ponies don't come from the displacement, The turbocharger compressor wheels are larger, by how much? don't know...

Has anybody swapped out the compressor wheels on a 600 to see if this is truly the main difference???. I also know MKB seels a cam for the 600 motors, so does brabus, my thoughts are they are using the 65 camshafts and dropping it into the 600.

MarkoCL65

This kit will be renamed very soon anyways. And I'm not talking about the numerical part.

320 dreamer

be glad to meet you on the 12. sure wish that beautiful car would join you!! tony's tune would really wake it up

V12Godspeed

Its about time...what took you guys so long...lol!

Gondon

Spill the Beans

NEMES1S

anybody have an update on this cam swap?

JAYCL600

The turbo's are both variants of the K24. The 65 turbo is larger in every way, it has a larger compressor housing, a larger compressor wheel, a larger exhaust wheel, and a larger turbo inlet. Keep in mind that although these differences are minor, they are enough to allow the 65 turbos to sustain a higher boost level and stay efficient.



drive safe JC, talk to you soon

V12Godspeed

Are you sure Jay? I would agree on the larger compressor wheel and exhaust wheel...Don't see the compressor housing being any larger. It just wouldn't be cost effective for mercedes to remake the housing , Just exploring the difference between these 2 beast, I like this type of conversation.

Pictures below are from 2 V12's...

Left one is CL65 , Right one S600

DCMETRO22Z

Renntech Swapped SL65 turbos on Hartmut Feyle's personnal SL600. I Pm'ed renntech they told me they had a 20Hp Gain.

Brabus Do not sell Camshaft For any MB V12 Twin-turbo Engine.The only Camshafts Brabus Offers are the ones Found in Their 6.3 Engine conversion.

MKB Has camshafts but they won't sell them as a separate item.

DCMETRO22Z

As Far as I know, SL65 AND SL600 Share the same Turbine Wheel Housing. Only Brabus offer a significant larger Turbine Wheel Housing.

I'm Pretty Sure The housings are the same. Only the size of the wheels change.

V12Godspeed

Are you serious??? What's the secret then...could it all be a combination of things? i wonder if injectors along with cams and displacement make the remaining 80hp difference. Thanks for you input well appreciated.

DCMETRO22Z

I think we must not forget the Marketing side of things...

I think mercedes could easily Find 612hp in The 5.5 Engine ... But how to explain to customers that they paid $75000 more over an 600 just for an ECU tune and a Bodykit... That's why they over-engineer some cars.

A SL600 doesn't need anything else than An ECU tune to make 65 Power...

It's like Brabus Who needs to cast new Exhaust Manifolds for the 65 to Justify the price of their stupid T65S kit that makes 720 Hp for 20,000 Bucks, and has absolutely no Cooling upgrades...

A lot of technical features are not justified. The O.5l the 65 has over the 600 have no reason exept to justify the "65" name...