darren_dallas

I just went back and watched the videos in the order they were taken. Here is a summary of the results:

run 1: from a standstill, sl55 win (no video, great launch by sl55)
run 2: from a roll, sl55 win
run 3: from a roll, m5 win
run 4: from standstill, m5 win
run 5: from standstill, tie (no vid posted)
run 6: from a roll, m5 win
run 7: from a standstill, m5 win

I'll leave it for you guys to interpret the results. Makes for good conversation either way. Hope this helps.

Regards,

Darren

BenzoBoi

Thanks for the reply. I was just makin the assumption under what bfnnrgn was saying. But I guess the video speaks for itself...

we need more M drivers like you...

darren_dallas

The data sort of supports the theory depending on when you think heat soak starts to set in. Would be good to do this again.

Actually, we're doing Ennis 1/4 mile drag strip this Friday. Maybe Robert and some of the other DFW ///AMG guys can join us. Should be loads of fun.

Regards,

Darren

bfnnrgn

I agree, at this point we're just making guesses and that doesn't serve anyone. More testing would be a good idea, and lots of fun to.

I'm game for Ennis, I've never been there. Sounds like fun. What are the details? I'll be sure to bring my laptop and datalogger for anyone who wants to use it as well. Maybe make a new post announcing it so others can see. I'll send a few PMs out to.

MB_Forever

Excellent data, and seems like the results are divided down the middle....

Looks to me that the cars are very close in performance, and who ever got the better launch took the lead. I'm sure heat soak also played a role. For forced induction cars, it is very well worth it to install some kind of a cooling mod.

AMG Rider

Guys, give M5 some credit! It seems like everyone is trying to make
excuses everytime especially heat soak issue.
I think the result is pretty much what i expected.
plus that SL55, i believe, has an aftermaket HE. i could be wrong on this.
I love both cars and nice runs!
I would like to see after SL55 gets some header work done to it.

bfnnrgn

It's the stock cooling system except for the pump. I should have put a new HE on with it but did not.

I don't think anyone is trying to make excuses, just some enthisiasts speculating about a few races. Honestly what does it matter as long as everyone had a good time?

TopGun32

run 3: from a roll, m5 win
run 4: from standstill, m5 win
run 5: from standstill, tie (no vid posted)
run 6: from a roll, m5 win
run 7: from a standstill, m5 win

===========================
thanks for the score card...


all M5 wins after the 3rd run... (except for run5)

NO excuses.. its part of life with this engine.


its like a heavy weight running.. its needs time to coold down and catch its breathe.

Zod

Question is, is this matter related to sock or pulied cars more?

I am starting to wonder if the pulley upgrade is worth it
few cases of them performing well a few times, then its a nose dive to a performance level that can be even worse then stock
This is in a relatively coolish weather country to...

stevebez

Nice runs and great to see some unbiased reporting...

What is the lag in time needed for the M5 LC to be used?

When you add a pulley or increase boost in anyway (not sure how else?) you have to sort out the heat exchanger and pump ... in stock mode they are at their limit.... in modded form they cannot keep up... add some high ambients and forget it.

Pulley is definitely worth it but you have to upgrade the coolling.

Zod

Its alive!!!!
where has the old goat been by the way havnt seen u in a while!
did the mod bug get to you

TopGun32

more boost spells hotter air.. after a few runs it will hit the max IAT's sooner..

stock probably would be able to stay more consistent but you will have less power at the beginning.. and reach that point as well.

even in cool weather... once the engine is hot (right around 100C) there is just no way way to cool down the air unless you have a bigger heat exchanger and heat spacers (I'm doing next)

That still does not keep your car reaching high temps but remember the key is the recovery times.

If you plan to do a few street light races.. a pulley alone is good enough..

if you plan to run back to back to back against a sports sedan machine like a M5, not a good idea with stock HE and bigger pulley.

how do I know.. I ran my car with stock heat exchanger and bigger pulley for 1 year..just adding the heat exchanger the power is constant and I don't feel the power drop off after 1 hour of driving.

kipper215

With forced induction heat is always the enemy and the engine will pull timing to save itself. the M5 does not suffer from that handicap. an old race car driver told me HP keeps the pace, but torque wins the race. The M5 is a topend car that really shines hard on the freeway. my frind has an M5 and we when through the same thing. once heat soak settles in you may as well call it a day and grab a bite to eat. Hands down the M5 delivers the most engaging driving experience. high revs and sweet exhaust notes makes that car a 10. the refined muscle car sound the 55 is no joke either. either way it goes both cars are winners in my book. I look forward to the day when I get my M car.

vrus

Hey Darren!! Glad to see you are enjoying your M5! I am hunting for one myself..

Just get ready for the rematch... We are going to get Robert's 55 cooled down and then its time to re-run them.... hahahahaa..

Great cars and looks like you both had some fun!

Robert: I see you are enjoying the car!!! We've got some goodies waiting for you in Houston whenever you are ready.. lol...