Cam swap / tune question, need help fast !!
Just did a 209/217 .550/.550 112lsa cam swap in an lm7 5.3 half ton 2wd truck and a 4.11 gear swap with new bearings at the same time.
The guy who was going to do the tune said to fire the truck up, if it's drivable then bring it out (about 15 miles away) -- So I did and it runs good and is totally drivable on the stock tune. Idle is rough once it's warmed up but thats it. No codes or anything either.
The directions on the rear end gears said three 10 mile trips with 30 minute cool downs and that was it. Well i just called the manufacturer and they said wait 500 miles before any wide open passes.
So now it's short notice but I dont wanna take any chances on my new rear end. My question is, is a base tune really necessary given the truck seems to run fine, and also not going to hammer on it. In other words is it safe to do the 500 miles on the stock tune to break in the rear end and then wait for a dyno tune? Or should I still go out tomorrow and get a base tune? Just not educated enough on tuning and pcms and what not. Kind of my understanding at the moment that a base tune is required in more radical cam swaps just to get the vehicle to run and idle and what not to get out to the dyno but I kind of screwed myself by doing the cam and gears at the same time.
The last set I had done up lasted about 10 miles before I hammered the **** out of it. But the car had street tires that broke loose with ease so it wasn't real hard on the gears. I wasn't very nice to it after that either and they were fine.
I'd drive it the 15 miles to the tuner. Let it set a bit. Then go tune it. Then let it sit a bit. Drive it home. Let it cool. Then plan to do some cruising over the next week then let it eat.
The base tune is more important than the super soft gear break in in my opinion.
Just be nice to it is really the main thing here. But the base tune being far enough off could cause some serious engine issues, so I'd make the base tune a big priority.
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