RKD in OKC

Visited Lindsey Racing this Saturday at 425 miles on the new 2.8. Dave popped in a different chip, cranked up the boost from 6 psi to 13 psi, and we took it out and did a quick tune check. It was a lot smoother. I also got the okay to raise my break-in rev limit from 4000 rpm to 5000 rpm. Weeeow!

The combination of 2.8 stroker and 8.5 to 1 pistons made the car feel pretty powerful at only 6 psi boost and 4000 rpm limit. The car is faster than traffic and doesn't feel anemic at all partial throttle and shifting at the Manuals recommended 3000 rpm. But it was a bit of a hassle shifting to 2nd in the middle of a turn from a stop. Especially when the turbo hits at 3000 and 4000 comes up so quickly

Raising my rpm limit to 5000 makes the car a lot more natural to drive. Mostly in those situations when you need to accelerate out into traffic or around a corner. The increase to 13 psi of boost makes the car feel every bit as fast as my 2.5 liter was at 16 psi with the same turbo. I've already found myself sideways and drifting the corner more than once. The time it now takes to accelerate from 3000 rpm to 5000 rpm is the same as it was at 6 psi from 3000 to 4000.

Oh and the sound. I went from stock headers and downpipe to the new LR header and 3 inch downpipe. The rest is the same LR 4 inch with Magnaflow. The change in sound is hard to describe, it went from what I would call raspy and loud to musical if not melodious. I can't help but roll my window down and rev it a few times as I go under an overpass. It makes the hair on the back of my neck stand up, sounds like a well tuned race car!

I am spending a lot of time out doing break-in accel/deccel driving because I am anxious to see what it is going to do with a full tune. Since the motor is in break-in we haven't bothered to scale the MAF. That's tweaking the fuel pressure and MAF output to get the maxium voltage from the MAF at maximum air flow and correct AFR. Not only am I going to see more power from cranking up the boost to a final 17-18, but I know from experience scaling the MAF makes a huge difference too. Come on miles, I wanna go dyno!

dime1622

Sweeeeeeet.

944CS

why do you have to do break in miles? It may sound like an elementary, dumb question, but I do not mean it in that way. If all machining was done well, seat the cam and go!

RKD in OKC

I know there are a lot of race shops out there that do the run it at 4000 rpm for 20 minutes to seat the cam and go. I also have heard of break it in like you are going to drive it. When I bought a brand new 2001 Boxster S it had break-in instructons of limit to 3/4 throttle and keep the rpms below 4000 rpm for the first 2000 miles. My 2007 BMW X3 said no full throttle till 2000 miles (no full throttle keeps the rpms below 4000, automatic transmission).

Lindsey Racing did the build and install. They are giving me break-in instructions so I am following them.

Machining a surface does not make it perfectly smooth. Even honing and polishing have their limit when it comes to mating surfaces that move against each other. The mating surfaces polish each other for a perfect fit, this is called lapping. Assembly tolerances allow for this lapping process to wear away some of the material. If you run rpms to high before the lapping process is finished you run the risk of both oil starvation and high localized temperatures that would either damage the mating surfaces, or cause more material to be lost to the lapping process than desired due to expansion.

The lapping process is also why you don't maintain a steady speed. If you did you would only load one side of the bearings. By accelerating and decelerating you provide pressure in different directions so the entire surface gets worn in evenly.

xsboost90

wear your flames off yet?

RKD in OKC

Washed em off Sunday Afternoon. Miss them already.

ENGINEERMAN

Congrats! Dave is great and I hav enever had a bad experience with anythng that he makes.

I'm sure that you'll remember to change the oil after the break in is complete (get rid of all of those little break in particles) but I just thought I'd mention it.

Again, congrats!

Guns951

You're a better man than most...the dealer said the break in on my 550i was optional...he he he...so what did I do? Loud pedal going sideways out of the dealership. I'm sure i'll regret it but screw it.

Get us a sound clip FOR THE LOVE OF GOD...don't tease us like that with the 'melodius' comment unless we can enjoy too! glad you're having fun.

Enjoy in good health.

RKD in OKC

Will try on the audio clip, but I haven't had much luck recording and it sounding very good. Maybe a real microphone would help :L

TRWright

for the discipline it must have taken to drive that thing around under 4k rpms and @ 6psi !!

porshhhh951

noice!