The rotor is a bit scarred. The side seal grooves have a couple little burrs protruding into the seal area. I'm thinking I can shave those down and be OK.

I tore the whole motor down. It seemed silly to not do it since I had to crack the keg open anyway and it's not that much more effort. Okay, yes it is, but I'll feel better.

The sideseal to corner clearances were all .002" side seal to corner seal. No marks on the corner seal. I didn't measure the side seal to side seal groove clearance for some reason (because I forgot, shockingly?) but the seals all moved fine when I tested them in the dry install.

AWR is Anthony Wood(something) racing. They sell those rear camber adjusters. So do some other vendors.

 

i would have torn it all down too, sucks, but that way you get to look everything over again.

 

those are the MMR camber adjusters.

http://www.mmr-direct.com/

sucks that the engine blew already hopefully it'll be back together and broken in by 4/18 for the first scored WDCR event.

 

Indeed they are, thanks.

 

Didn't find anything else funky in the motor. Front rotor was happy. Reassembled the whole thing and re-did the rear rotor with a new side seal and more attention paid to getting the clearance right (I opened all of them up to .003 just to be on the safe side) and getting all the burrs and sharp edges off the side seals. I really don't know what caused the problem. Bad luck? I don't really buy that but I didn't find anything else wrong.

Motor is back in the car. I'll probably take it out to the event this weekend and just take it easy... need to get the suspension set up so I can't really pass up the event. No WOT and nothing over 5,000 RPM I guess..

 

Wow. You must have had many long nights recently...

I hope to see the car Sunday. If the forecast looks crappy, I may not make the 2.5hr drive (one-way) though...

 

No long nights. These cars are pretty simple and it's easy to pull the motor. The most time was spent just checking everything inside the motor, looking for general weirdness.

It was annoying to have to tear it down so soon but that's part of the game when you do stuff yourself - sometimes you screw up.

 

Sometimes that happens when you pay to have something done as well. So at least you have knowledge, and knowledge is power.

GD

 

Yes well... I would much rather screw up and have only myself to blame rather than deal with another person's screw ups.

Motor is back in and running very well. 15 miles on it so far with no issue. Fingers crossed, I guess.

 

200 miles and zinging up to 6,000 RPM with no issues so far, knock on wood.

My LC-1 Wideband controller failed. Gotta send it in and get it repaired. So for now, working on the stock tune through the Rtek. Seems lean down low and rich up top, just based on throttle response, but it's definitely a quick car.

I'm teaching an autocross school this sunday so I'll get to shake it down

 

That's good to hear!



So is the noise level of the exhaust tolerable on the street? Getting any 'extra' attention from the local PD?

 

i have a feeling you know how to tune you car, but ive had a pair of S5's and leaning out both of em up top made a HUGE difference. even with stock intake and exhaust.

stock air fuel @6k is like 11:1! just by the butt dyno, mid 12.5 you get most of the power, going leaner than that was subtle

 

Thank you for the input. I have gotten that feedback from others as well. Right now I don't have the wideband installed but once I get it back from being repaired I will start logging.

It's been suggested to me that I target 13-13.5 AFR for best safe power.

Chike, the exhaust is f**king loud. It's tolerable but it's never going to pass sound like this. I'm going to move the magnaflow forward and put a cheap "turbo style" muffler at the rear.

 

So what was the idle problem and how did you end up resolving it?

Glad to hear things are up and running again, keep us updated.

 

your AFR numbers are in the ballpark. i don't notice much difference between say 12.5 and 13, so i'll tend to leave it richer, but thats on a street car too.

the race car made best power @13.1 richer or leaner made less power, on the dyno, ymmv!

 

Once I get the tune sorta-kinda close on the street I'll be taking it to the dyno to play with a few things and AFR is one of them. I have an hour of free dyno time here which isn't much, but I can always buy more.

I'm more excited that I'm teaching an autocross school this sunday so I'll get some play time to dial the handling.

 

I agree. On my car it feels nearly the same between 12.5 and low 13s, but EGTs are slightly cooler in the mid-high 12 range. I hear a lot of NA guys say you want to be around 1600-1650F EGT for the best power, and based on what I have seen from my tune I would say that is about right.

I haven't been on the dyno with it, but advancing the timing 3 degrees from about 3K to redline helped noticeably. I know the S5s have more agressive timing from the factory though.

 

how'd the auto-x school go?

 

i found the same with the timing, the s4 really wakes up with a couple more degrees, the s5's ping, next time i'm going to try running about 1 degree retarded from stock!

 

It was good. I got to drive a Caterham set up for DM, a BMW M Coupe, a few Miatas, an M3...

Oh you mean the GTUs? First impressions, it's slow as dirt. Really sluggish coming out of slower corners. Also a bit pushy steady-state so I wasn't able to get on the gas as early as I wanted. But it transitioned really nice and was well balanced on corner entry. The brakes aren't fully bedded in yet, so they weren't working at 100% either.

Last night I broke out the strings and plumb-bobs to check the alignment. I thought I had dialed in about 2 degrees negative camber in the rear but I then remembered I lowered the rear end a little. So it was sitting at 2.5 on each side. I re-set it to 2 and then adjusted the rear toe to zero. I'll try it next weekend and if it's still pushy I'll try raising the rear, pulling more camber out of the rear or going up a little in rear spring rate (sitting at 450 in the front and 350 in the rear, with an ST front bar and the stock rear).

My times on this little practice course were about a second off of Ian's CRX, so it's in the ballpark given that I'm way down from the power I should be making and the suspension isn't dialed.

Best part - nothing broke!

 

I imagine most things feel slow compared to a caterham and a BMW M coupe

for some reason I didn't make the connection that you're in the same class as Ian, that's going to be rough But it's a nice bench mark so you know what to expect when you go to nationals.

a bigger rear sway bar probably wouldn't be a bad idea if you want it to rotate a bit more. I've heard a lot of NA guys like them because they don't really have issues putting power down. I've driven Molotovman's GTUs and it feels great with a bigger rear sway bar.

that being said, I took the rear sway bar off my TII for the WDCR event and it was probably one of the best mods I've done but my car would kick the rear end out all the time.

 

Not too shabby for your first outing in a new and untested car. Were you taking the car to redline? Glad the engine is holding up.

 

I was observing a 6,000 RPM revlimit as best as I could.

For reference I ran a 28.2 in the Caterham on that course and I used to run mid 30's in my Boxster S and 30 flat in the Z06. That kind of suggests I need to run around 31 flat in the RX-7 to be on par with those cars. Long way to go.

I will see if I can pick up an RB rear bar and do some testing with it. Fortunately alignment changes are relatively easy on this car so I can play with rear camber and toe as well. Normally I like my cars pretty loose, especially if they're low powered.

I have to guess that the car is going to pick up a lot of top end with a tune, but the low end probably is what it is...

 

different animals, but our ITS car was similar to yours, we always ran zero toe, i forget what camber was in the rear.... probably like -2 something...

the drift car (it was the guys DD too) was kind of a "strange" setup but it worked really well. ride height was high, like 26" (my stock gxl is like 26.5 or so) from the ground to the top of the wheel arch, zero toe, and zero camber too. he ran 350/250 springs, stock bars (it was a street car)

it did drift well, but it was really a good all around setup, it ran well at infineon too.

 

I've got a big front bar on the car (ST 2-way, set to soft on both sides) and the stock rear bar. After a quick blast around a favorite backroad, it's better with less rear camber while still being biased towards understeer steady-state. I'll probably take out a little more rear camber before trying a larger rear bar. I've never been a fan of RWD cars with too much rear bar, as they tend to get very snappy.

John