I told them I may have a chance to buy a used Renntech pulley and asked what it would be to just get the ECU tuned for that pulley I was buying. The guy I spoke to said they simply will not do a tune for a used Renntech pulley. He said I have to buy a new one from them or else no tune. He said that they have no idea if they tune it for their pulley and I go ahead and use that tune with another pulley and there is an issue they look bad. I guess I can kinda see their point but I thought for sure they would tune my ecu if I told them I had their pulley in hand but I guess not. I even went as far as to say if I take a pic of their pulley on my car if they would tune the ecu and again he said no way.

I also asked well what if I just install the pulley and no tune. He said that if I do this I will destroy the engine. He said it is not if it is when. He said by changing the pulley you change the A/F to much for the car to compensate for that. He said anyone that tells you that you can just do a pulley change with no ECU tune has no idea what they are talking about. I told him there are many people on a board I am on that have just done the pulley and no ecu tune and they have no problems. He said well they are making a slow but more likely a fast death for the car without the tune. He said they have done this for many many years and by not tunning the ecu to the pulley will ruin your car period.

So I assume the safe thing to do is if I just do the pulley make sure I get it on a dyno to make sure the A/F ratio is in check?

I know I have asked this before and gotten the answer of the car will compensate for the extra A/F needed for the pulley without doing the tune. I was all set to do just the pulley install but his comments scared the crap out of me by the time we got off the call

So my question is are they just saying this to sell a complete package?

I even asked if they would just sell me the pulley and they said no way, not without a tune.

Any thoughts? I know Renntech is highly respected with tuning MB cars.

Thanks

 

In a word YES.

Can you say MONEY boys and girls

I don't have a tune, and run just fine. I even pulled a plug or two to double check. I can FULLY understand how this would scare the cr-p out of you my friend. So do yourself a favor, call LET, Erick or Jerry will gladly talk to you, or call ASP. A TUNE is NOT mandatory for safe operation. Yes it can give you some more power, but alas at a HIGH price IMHO. MANY guys here run cars WITHOUT a tune for this reason alone. Good luck

See yeah

 

+1, for the most part. I believe you should have it tuned......but,

Anyone that knows how to tune your type of engine and is good at it, can tune it, not matter what brand pulley you have. Stuff like what Renntech is trying to do to you drives me insane. One of the many things that bothers me about modding these cars. In the world I came from before this (Chevy LT1's)- no matter your combination- someone that was good at tuning, would accept the challenge, no matter the parts combination.

 

Thanks that is what I thought.

He ended the conversation with me saying if you want to ruin your car then just do a pulley and you will see. He said there is a reason why they do not sell the pulley without a tune. I almost said ya money. He said the difference between their co and others is they care what happens to the customers car not just making a buck off them . I asked him what about all the other companies that will sell a pulley without a tune and he said there is always people waiting on the corner to make a quick buck at your expense.

 

Heres what I would tell you if you can.


find a RENNtech dealer nearest you that has the ability to flash your car. Then ask them if they can do this for you, as they can tell RENNtech that they are install a RENNtech pulley and need software for it.

Good luck!

 

True

My next step is to see if I can find someone in NH or MA that tunes MB's.

 

Good Idea

I asked him if there were any Renntech intsallers in NH or MA (Where I Am Located) and he said no.

 

My local MB dealership is a Renntech re-seller. Although I cringe at the thought of going to the dealer to get after-market parts and support.

 

The way I see it, there's several issues in play here.......
Let us all keep a couple of recent infamous threads in mind:

1. Would they prefer you purchase a complete package?
Absolutely - more money for them.

2. Are they covering their rear-ends in terms of liability?
You better believe it. I would do the exact same thing. There's no way they'll do a tune for a used pulley. What if they do a tune and the used pulley is damaged just ever so slightly to the point that it isn't balanced correctly? Check out Renntech's liability waiver on-line.

3. Is the AFR altered to point that the ECU can't compensate? Maybe, maybe not. As alluded to ad nauseum, these AMG motors display significant variation from vehicle to vehicle. Some people's cars may be just fine with pulley only in terms of AFR. Some cars may not. "Some ECU's are more equal than others".

4. Can you assume that 'pulley only' is fine on your car?
Given the number of stories on these forums, NO. And what exactly does 'fine' mean? Does it mean a subtle deleterious modification that may damage your car in 10 years versus way off AFRs to the point that your motor can go belly-up in 6 months?
That's for you and your tuner to decide after the appropriate amount of data-logging and dyno sessions.

5. Unless proven otherwise, why does anyone assume that a used pulley is in good working order? We've all seen the state of many crank pulleys that are pulled off these kompressor motors. Some are fine, but I've seen many pulleys that have cosmetic damage to the point that there is just no way that they are balanced correctly. If you purchase a used pulley (especially ASP), spend the little extra $$ making sure it is properly balanced. There are plenty of E55 forum threads that highlight this necessity.

 

Agree,

Make sure that the pulley you have is in good shape as you do not open the hood everyday to check. Many forum members do not have a tune with a pulley, don't know why Renntech insisted on a tune and replied in such a way.

I am waiting for my LET pulley, the stock pulley on my car is in bad shape and thats why I decided to order a better one. My car has 35,000km on and the pulley is due for replacement.

 

What ever your future holds much luck in finding the proper answers and welcome to the faster lane...

 

PLEASE give me a call...i will be glad to explain the TRUTH to you in regards to tuning...

if you don't want to give me a call, then shoot me a PM...

 

They are just covering themselves as I would. If they did the tune and the pulley was bad or something like that they do not want to ruin their great rep over a software only sale which I can see after thinking about it.

 

Erick
I will call you today to discuss. Spring is right around the corner and I want to be ready

 

Best route for you to take both Erick and Jerry have delt with this stuff for a while now.....

 

Go with LET....

 

Any good MB tuners in Northern, MA? When I go with the pulley I will want to bring it to a tuner to have it dyno'd before and after. I will also want the A/F report to show me I am not running a lean cond. I can not find anyone in NH. A lot of Stang tuners and thats about it.

 

bud4ya, I think RennTech's position is understandable. Consider they sold you the ECU tune and then you used it with an ASP pulley or any other size pulley (or even a bad RennTech pulley) and then something did happen to your engine. At this point, the blame game will start and believe me, finger pointing will be fast and harsh:

Pulley maker will blame ECU and ECU maker will blame pulley, and we'll essentially never get a straight answer.

RennTech probably wants to avoid such situations. I'd be more cautious of a company that tries to sell an ECU tune for "any" pulley than a company that tries to sell one ECU tune for only "one" pulley (namely theirs). I know RennTech is one of the most expensive, but in my opinion, their also one of the most reliable. They spend a ton of money on Research and Development and know our cars very good. I personally seen RennTech products in action and can vouch for them. My friend's SLK32 had a RennTech Stage 1 and he kept it until 90,000 miles with no problems. Also, the current owner of my C32 has removed my Evosport pulley + powerchip software and switched to RennTech pulley + custom software tune and showed +33 whp increase on the dyno. Also, Jerry have used RennTech products and his car ran very strong.

Aside from RennTechs' rediculously high prices, I see only one more downside of using RennTech: if you get their pulley + ECU package, then you're pretty much stuck with that setup for a while, so you better make sure that a pulley + ECU is as far you want to take the car. They will not be very helpful when adding additional performance parts for the same reasons they already mentioned. But if you go with LET, they can at least custom tailer each stage for you as you need it.

 

I agree with everything you mentioned. Calling LET tomorrow to discuss options

 

With all the smaller tuners avaialable.. Code 3, LET, VRP ect..

I'm not sure why the bigger tuners insist of pricing their products as "exclusive".

There is nothing exclusive about a 3 to 5 year old car that is out of production and has a bad resale value.

Pulleys are not that expensive and tuning should not cost $1k for a car that is out of production. By now all the R&D dollars should have been recovered, if not they should not be in business.

Take Acura,Honda, Nissan, Infiniti, Suburu and even some of the BMW tuners are pricing their products much less than before.

Economy is bad, housing market is bad, lots of corporate down sizing.. is not that easy to peel off $3k for a stage 1 pulley/ecu combo, if the car is only worth $18k????

back to the topic,

buy a larger pulley, install a larger FMIC, don't due the ECU and your car will run with no problems.

 

WOW did you ever hit the nail on the head Topgun32

All I can say is +1,000,000,000 It's absolutely INSANE what is being charged for a ECU tune on our cars, or any Mercedes. If we were a C63 I could "ALMOST" understand it, that is ALMOST.

See yeah