oh what they used a stock intake? dam... well i did email and ask for suggestions. so lets see what they recommend!

i keep seeing modalworks and other BMS ones that give 20-30whp improvements especially at higher RPMs

 

yep. They said they’ve tested and there’s no need for anything beyond stock piping with the BMC filters. I’m going to trust them on that given that it’s an actual AMG experienced engineer running their shop.

 

If you've got a stock intake get a BMS intake on there ASAP and pickup huge power up top!

 

I shall order some!

 

what should i be expecting? is this even good? power dropped off higher up. i've read that c6 Z06's can doo 8-8.5 seconds 60-130 at stock? how am i doing 10.5?

 

did you do the plugs and get good gas?

 

plugs are yet to be done. any recommendations ono which to order? or just do stock?

i cant get the better gas as borders are still closed. but atleast now i know the 60-130 time is terrible and something is def wrong here. others are getting 8.5 ish while i got 10.7?

 

Renntech just advised replacing with factory plugs

 

Thats correct. As mentioned factory plugs and gap.

 

@rbohgan Have you been able to get this sorted out as of yet? If you changed your plugs already, how did they look?

 

Hey

No with holidays here couldnt bring in the spark plugs yet. will do them this week.

Nothing is resolved as of yet. But on an e85 facebook group for local tuners here in canada they advised trying 15-20% ethanol mix and see if i notice a change on 60-130 pulls.

Renntech have been giving me answers I don't quite understand. I asked for data on what sort of 60-130mph tests I should aim for. To know how far mine is off. They said this

"Stock 60-130 10.51Ecu + downpipe 60-130 10.886 traction is an issue with those cars"

.... im confused. so i was expected to become slower? i have no traction issues at those speeds.whats everyones thoughts here im starting to get frustrated lol

 

that is a strange response. They may be correct, however. Stock, my car wouldn’t break loose at 60. Now it does with my Renntech tune. If you leave TCS on, it will cut power for a second and then roll on again. With TCS partially off, my rear will get squirrelly punching it at 55-60 mph

 

i dont recall any slipping when i punch it.. checked my dragy video too and was no slip

what sort of 60-130 do you get with renntech tune? i always run mine with TCS partially off.

 

No idea. My car is just notably more powerful with the Renntech.

 

hm im gonna try my 60-130 again with TC off. spoke to another guy with a renntech tuned car he said do that. TC kills our cars performance. so ill try anyways

also dealer said $900 to get spark plugs changedd...wtf lol

 

That response seems to indicate they assumed you wouldn't realize your car was spinning the tires. I find it hard to believe you wouldn't have noticed that, though.

$900 for a spark plug change!? That's insane. I just got my car about 7 months ago so I haven't looked into spark plug changes as of yet, but I would call around to some local shops for a quote.

 

i know i was blown away lol parts are super cheap too.

 

For compare the best way is to mess 60-130mph

 

what they said doesn’t make sense , there are plenty of cars on the dragy leader boards with more power and mods running faster times, using their logic this should be impossible due to “traction” when you floor it it may initially loose traction (depending on what tires your running) but It should hook up and go, I always run my 100-200kmh with traction control in sport mode and the trans in manual mode to stop it short shifting if it does break traction.
running some ethanol or octane booster would be the best thing todo for now

 

agreed...what they said makes no sense. I don't have the screen shot I saved of mine from last summer, but in reality you should be running sub 8.5 seconds with a stage 2 tune 60-130. I personally never put more than 3 gallons of e85 in my car, but you certainly notice a bump when you do add a couple gallons to a full tank of 93. Additionally, like everyone here has stated, you need to get your plugs done asap, recommend finding a good indy euro or tuning shop to help, as it should not cost more than $500ish dollars. While youre at it I would change the oil to some liquimoly (or motul) and add some ceratec (can buy from fcp euro in a kit). I bought my car used with 12k miles and tuned it a week after I bought it, these cars are known to have issues in cylinder 5, and mine was a victim as well...so when they pulled the plugs we noticed cylinder 5 plugs were torched. do those things, try and reflash tune and then see where youre at. I would have hoped that your tuner would have advised you to do these things prior to flashing, but again, it doesnt seem like he was very invested in helping you. Just my thoughts...

 

When I got my Renntech HHT they advised me to do plugs since I was approaching 30k miles (and had misfires on another tune...cylinder 5 btw). I blame the other tune far more than the plugs, but wanted to eliminate any weak link in the chain. Not sure if OP ordered the HHT, loaded it on, and then just had the shop dyno it, or if the shop was somehow more involved. (Not sure how much more involved they could have been. You plug the thing in and press a button).

Anyway, I still advocate just doing the plugs yourself. It’s not hard at all and saves all the labor cost. Plus maybe you learn a thing or two.

 

Totally agree on doing plugs yourself if you can gap them properly. The OP said the shop was basically there to flash and dyno, but still, anyone going stage 2 on nearly any vehicle should address plugs and oil first. The other concern which I only just now thought of, is what mercedes software version the tune is based on. Hopefully its the latest one. But you never know. I noticed a huge difference after redoing my tune with newer mercedes firmware, especially with the transmission response.

 

Sounds like the Renntech tune isnt great, and your results are what is expected by Renntech. Their responses have been disappointing. i could see 0-60 mph being slower due to traction, not 60-130 mph though. Even a little wheelspin at 60 would be easily offset by being MUCH quicker for the rest of the run.

As a data point, I ran 8.3 with JB4 map 5. tune only, no intake or dp.

 

A bit outlandish to say that the Renntech tune isn’t great due to acting odd on one car that has bad gas, old plugs, third party downpipes, etc. In post 14 he even says the car knocked on the crap gas he’s using.

Renntech is probably one of, if not the single, most reliably proven tunes out there with the most AMG dedicated knowledge behind it.

I can’t speak for what OP is saying to Renntech, or how he’s communicated with them other than some cut and pastes from emails, but when I have questions for them I pick up the phone and get clear, simple answers.

He needs to remedy the bad gas and old plugs, re-dyno, and if there is still something odd, pick up the phone and talk to Renntech rather than trade notes on 60-130 times.

 

Look, I agree OP might want to call, and I know what OP needs to do. And I am familiar with Renntech's rep. But if Renntech thenselves think 10.x with a stage 2 tune is normal, thats not great.