PorKen

IIRC, the Racelogic box comes with a wiring harness which has individual injector wires. You connect the batch fire signal into the box, but the RL system turns off individual injectors.

(Installation manual)

It'd be cool just for the launch control.

Rob Edwards

Ah, gotcha. I could REALLY use launch control, spinning wildly is fun for a while but not being able to hook up consistently is tricky. (Most of the problem is lack of behind-the-wheel talent, but the pedal effort with the DD is really light and hard to modulate- even with the assist spring undone completely. Hoping that the new clutch will help. Will see in a couple of weeks.)

GregBBRD

Actually, I am working on a couple of things....

I've been able to see the weaknesses, first hand. Mark Anderson has "provided" me with lots of blown up gearboxes to study.

He's probably the best driver I've ever seen....adapts to anything, with any kind of tires/suspension, at any track....he just drives.

However, he can break a crowbar in a sandbox.

GregBBRD

And none taken.

I'm just trying to answer questions.

I did think more about what you were pointing out. The 928 rod is actually wider than a "Chevy" based rod and my "new" rod. That actually means that the rod journal isn't as wide. This does make the counterweight wider, which is what you noticed.

Good catch!

BC

Launch control is available on many newer Aftermarket ECUs. Its almost common practice now and the algorithms are quite stable. It is not rocketscience as it was many years ago. It may not actually affect the longevity of the manual trans however. Its made to get to the very 'enth degree of traction without spinning wheels. Which will net the best take-off, but also probably the most stress on the driveline.

BIG 928

looks like some great engine **** to me!
i have used porsche bearings in my gts race car since 2005, i had a new engine in 2007 and have had 35 podiums since, including 14 wins, 4 of which were at spa which is notoriously hard on engines, so im not blowing my own trumpet but i aint hanging around, im flat out. ( im just tryin to tell people who i am most wont know)

my point being the engines have a lot of failures but the bearings arent made of cheese!
i use porsche oe bearings in my gt2 as well thats 700 plus bhp on a nice day if ive got to catch someone!
sorry to go off thread but i wanted my say, i think keeping the right oil at a certain level is critical as well. to much and it blows it out. to little and your in trouble anyway. maybe i use the englands equivalent of amsoil, but thats another story

GregBBRD

Agreed. The bearings are not made of "cheese". (That's funny, BTW)

It's not like we used to assemble these engines and blow them up, the first day...or even the first week.

As long as you feed the engines with a good supply of high quality oil, keep the detonation at bay, and keep the rpms down, the bearings will last for quite some time.

I figured out that if we watched the oil filters very closely and keep track of what was trapped in the paper, from event to event, engine failures could be kept to a minimum. When the bearings lost their crush, from pounding, it showed up in the filter and we would remove the pan and install a new set of rod bearings.

That being said...it is a known weakness, that has caused many engine failures. If someone (me) decided to build a "better" crankshaft, it would certainly make sense to address as many problems as possible, right?

That's all I'm trying to do. I've always thought that I was on the cutting edge of 928 technology and saw a "need" for improved crankshafts. I made some "major" changes to the "stroker" cranks and decided that I'd make a few "improved" cranks for people that run 5.0 amd 5.4 engines...especially those who want to take advantage of the "newer" camshaft technology available to us and want to "spin" these engines, higher.

Just trying to "improve" our 928's. No other agenda.

dcrasta

Hehehe. I do QA and tend to notice wierd things..

blown 87

That brings up a question, how often should us folks that drive our 928's very hard change our rod bearings?

GregBBRD

Whenever you see them in the oil filter. Bronze colored "chunks" are bad.

I find oil testing to be good, but generally I've found that the pieces come off in such large chunks that the oil testing can completely miss a bearing failure.

An oil filter is the "x-ray pciture" of what is going on, inside the engine.

I cut them open on every car that "sees" a track or gets the crap driven out of it.

danglerb

Doing a hard launch with a clutch (or an automatic assuming its set up for it) you release the clutch at a rpm and throttle setting so that the tires initially spin and then quickly "hook". I suspect that is you max torture on the driveline situation.

With launch control the idea is the reverse of ABS, keep the torque just below some percentage of slip, whatever max traction is, hard on the driveline, but not the same level of inertia driven jolt as the tires hooking up. Torque over time might be about the same either way, so I guess it depends on which failure mode you tickle.

BTW at some pretty modest level of power I think breaking manual transmissions is going to lose its charm fast, and until a better solution comes alone there will be a shift to not shifting (automatics).

Whatever happened to the guys in Europe that were working on a more modern automatic?

BC

Automatics will always be... automatics. And they are a compromise - even the new 200k "flappt paddle" gearboxes are not perfect.

andy-gts

automatics are able to better withstand the torque than the 5 speed....per a reliable source

Imo000

I was starring in my garage at a left over crank, from a Nissan 3.5 V6 tonight and looked different than the normal V6/8 cranks that I've seen in the past. At a closer look it dawned on me that each connecting rod is seperated by a counterweight and they are not paired up like a normal V6/8 engine.
Greg, I'm sure you've seen this before but what are the benefits of a design like this and would a crank like this could be of any benefit on a 928?

GlenL

Then again, is anyone tracking a big power 928 with an automatic? There's a history of breaking the gears on 5spds with strokers at the track, but is there a comparable use of an automatic?