New car runs sluggish....

[gbvetracer]

Did anyone notice their car run bad until you got miles on it? My car only has 2 miles on it, but when you warm it up and do roll on throttle revs, it hits about 5k on the tach and flattens out...like its loading up or something. It just "feels" bad and is not revving crisply like it should... My guess is it needs tuning really bad....like maybe its really fat. (rich). Any comments would be greatly appreciated..... thanks.......

 

[BlackICE]

Did anyone notice their car run bad until you got miles on it? My car only has 2 miles on it, but when you warm it up and do roll on throttle revs, it hits about 5k on the tach and flattens out...like its loading up or something. It just "feels" bad and is not revving crisply like it should... My guess is it needs tuning really bad....like maybe its really fat. (rich). Any comments would be greatly appreciated..... thanks.......

ecm is programmed not to allow full engine output until about 25 miles. It has been discussed on another thread.

 

[gbvetracer]

thanks for that post... I feel better now....

Now, if the weather would let me get the 25 miles on it! thanks....

 

[Neilda]

5,000 RPM on a new engine? :eek

If you'd like the engine to last, do drive it gently for the first 500 miles - even the first 1,000 if you have the patience. You'll be rewarded with an engine that should last a long time without being rattly and being oil-tight.

As explained in the earlier post, the injectors don't operate until you have some miles on it - for exactly the reason I quote, break in.

 

[gbvetracer]

different opions on break-in.....

Im NOT one to agree with your idea of nursing it around for 500 miles. There have been many posts on this topic...and most guys agree on varying the speeds, and not needing to break it in too gently. Most race engines have the snot run out of them right after the rebuilds....and they would know best how to get the most performance and reliability... I guess this is what makes cars fun, having lots of differing opinions.... I have always ran cars hard with virtually NO break in time, and never had any problems.... just fast cars in the end.... In fact the cars that are loaded up, bogged down and drove easy, end up never running as strong..... these things are built and designed to race...

 

[BlackICE]

I would agree with Neilda on break in. Race teams break in engines with the primary goal of getting the highest output from the engines that will also last the entire race. They don't have any concerns about oil consumption, emissions, or the engines lifespan after the race. The engines are always rebuilt after the race. A non-racing owner may have different goals. It is not to say that a hard break-in will shorten the engines life, but I have never heard of anyone explaining to me why it can extend its life.

 

[Neilda]

The handbooks on most cars recommend being cautious with new engine and I tend to go with what the engineers recommend.

Foot flat down motoring on a new engine would be like attempting the final chapter of the karma sutra on a first date - it's better that you build up to it! :biggrin

I do race cars too - and treat them entirely differently to my more precious cars.

 

[Empty Pockets]

Mine has < 300 miles on it, and it hasn't seen even 1/3 throttle yet. 'Think the most I've shoved the pedal down is about 1/2 an inch! Why should I use more? So far, I've been able to pass anything on the road I've WANTED to pass with just THAT! :lol

I DO vary the RPM's a lot - even within a given speed - by up & down shifting the car as I go along. I always try to keep the RPMS no lower than 1,800 -2,000 after the engine warms up. That, and using reasonable down shifts & compression to slow the car down (so the rings get "exercise"). 'Also will purposely romp it to about 8lbs boost now & then "just because".

But, nuts to all this hammer it all day long right outta the box stuff as far as I'm concerned.:frown :thumbsdow

 

[PeakCompletions]

I have always heard both trains of thought.

1. Drive it like you want it to be driven, ie. drive it hard out of the box and it will always handle that kind of abuse.

2. Break it in easy, varying rpms and frequent oil changes for the first 2000 miles....

I tend to lean towards 2. because number 1. seems to risky.

"Seat the rings early" ???

 

[Empty Pockets]

I tend to lean towards 2. because number 1. seems to risky.

"Seat the rings early" ???

I'm with YOU. :thumbsup

 

[ENZO BTR]

I agree you shouldn't base a street car's engine break-in on race team philosophy. :willy

I was pretty anal about varying the RPM and going easy for the first 750 miles (was intending to do it for the first 1,000, but then I got a chance to run it at Laguna Seca and...well...). But as Empty Pockets said, I also got a twisted joy out of being the fastest car on the road even when using no more than 1/2 throttle and a maximum of 5,000 rpm. :biggrin I also continued to methodically vary the RPM for the first 1,500 or so miles.

It run good now!! :cheers

 

[tpraceman]

The Shelby 500 has the same rev limeter program. I did some work on the black box and actually it is designed to keep the car transport and dealers from getting the itch to beat it b/4 the customer buys it. But it has a side beny of keeping us wild and crazy guys clam for a bit of a break-in:thumbsup

 

[MAD IN NC]

I was pretty anal about varying the RPM and going easy for the first 750 miles (was intending to do it for the first 1,000, but then I got a chance to run it at Laguna Seca and...well

It run good now!! :cheers

Hell - my philosphy is drive it like ya stole it..... Always did this, never had any problems