I'm very tired to dealing with the "bucking" problem. The specs are in my sig. I don't enjoy to driving my car, because I can't drive smoothly at low speeds. Especially while I'm in the traffic I want to stop, and want to walk!!

I have 2 choices:

1) Swap the trans from M6 to A4.
2) Switch the camshaft with a smaller one.

My current cam is 240/246dur. 113lsa, If I get something 220s will this help? I know for a 383 and 210cc AFR heads 210-220 durations cam will be a waste of power, but my primary objective is a smooth driving. I mean I don't want any kind of bucking, shaking like a horse. I don't want to change the tranny, because I spent lots of money to swap from A4 to M6, and I don't want to do it again. But if there is no other choice I will do that or sell my car after 6 years.

Any help will be appreciated.

 

are you sure its form the cam and not bad o2 sensors or something, and have you had it tuned before

 

I have the LE1.5 cam which is similar to the CC503 in specs.

I have very minor surging around 1500 in 4th or so when driving down my street, I can switch to 3rd and its gone.

Also my car has not been dyno tuned yet. The tune is critical on those larger cams, however a smaller cam will reduce the issue.

 

No Its not related to O2 sensors or something like that.

1500 in 4th? Oh I even can't imagine that. In 1st or 2nd, under 2200 its bucking like crazy. I have MADZ28 Tune, but I learned that it can't be disappear magically even with a perfect tune. So I think I will go with 224/230 or something like that. I'm worried about how much power I will lose after the cam swap.

 

All part of give and take I guess. It sounds like a smaller cam is in your future to get back the good street manners.

Look at a 224/230 cam like the CC503 or a hot cam, street manners are perfect after tune.

 

Yes I think I will get a 224/230 or 224/236 114lsa cam for my 383cid. It will a waste of power, but there is no other option I think. Oh and my 180lbs close pressure spring will laugh at the cam.

 

Do you have very strict emission controls?
Do you have to run it closed loop?

I run a 383 with the 847 cam with no bucking. I tried a few mail order tunes with no luck. Finally after searching a lot decided to follow some advise from this board and decided to run an OL DIY tune using the mail order tunes as a starting point.

You need a wideband and editing software and some time to log, but it is a difference like night and day between closed loop and a properly adjusted open loop tune.

What worked for me was running richer than stoich. Specially under light throttle conditions.

RG

 

No.
No.
What is the OL DIY tune?
Which wideband do you suggest me to use?
My car is 1997, but I swapped my PCM from OBD2 to OBD1 to use the tunercat for mail order tunes.
My MPG is also very very bad. In the city its below 10.

Oh man! Now I saw that you got A4! Torque converters eat the bucking and you don't feel it as the M6s.

 

OL DIY - open loop (no o2 control) do-it-yourself.
i have used the innovate lm-1 for wideband with good success

i would be doing some tuning before swapping cams, personally.

 

You get to feel the bucking in an A4 when your TCC is locked during cruising. Iknow what you are talking about.

I would give it a shot too before going into the engine and changing the cam back to a smaller one.

I used the LM1 wideband.

RG

 

Who are your mail order tuners?

 

First I got a tune from Ion Soltan (madz28) and recently I tried with PCMforless.

RG

 

Yes my tune is also from Ion. Okay so by using the LM1 I will make contact with him and tell him the datas, so he will send another program. Thats how it works?

 

I did it myself.
I had already done a CL Hotcam tune for my previous setup and was quite familiar with my editing software.
I did not consider sending data back and forth to have it done by the tuners.

I guess you would have to ask them.

You have Tunercat and an OBDI conversion. You cold do the changes yourself if you feel comfortable using Tunercat.
Its no biggie changing over from CL to OL and adjusting the F/A ratio if you have the right tools and time.

RG