redtopz

Sunday started out well enough. We have an agreement to only run 1 set of tires all weekend to keep costs reasonable. I didn't get a clear lap in qualifying but I managed to put down a 1:47.9 which was good enough for pole position. The race started well and I managed to get around a couple ST1 trucks in a timely manner. However, after passing the 2nd truck I noticed a Low Oil Pressure warning on my MXL2 dash. So I pulled the car over and shut it down. Basically, deja vu from Willow Springs with a freak mechanical failure. Here's the vid:


I sat and watched the rest of the guys finish the race. Chuck and Evan had a good battle and my friend Lee from Norcal finished 3rd. Jim and Robert have their car all done but had to run ST1 all weekend because they didn't have time to dyno class it.

What happened was my dry sump pump pulley gradually walked out of alignment on the shaft and the belt slid off the tensioner. I can see from my data that the engine was getting sporadic oil pressure for 1 lap and then the belt must have fallen off completely and the pressure dropped all the way. I caught it before zero, but I think my engine might still be damaged. I took it for a drive today and did some WOT pulls and started to hear a clicking noise. I'm waiting for a Blackstone oil test kit to arrive so I can have the oil tested and I'll inspect the oil filter. But I'll probably play it safe and have Synergy rebuild the engine to prevent catastrophic failure at my next race weekend.

redtopz

I made a couple improvements to my car's rear end. New OS Giken diff and new LG HD tie rods. Ever since my incident at Runoffs, my car has been doing weird things in right hand turns exiting corners. I think something is wrong with the diff. I've been running a Quaife torsen for many years and I was happy with the performance and durability. My first laps with the new diff felt great and I had to force myself to apply more and more throttle exiting the Buttonhook (a tight 2nd gear corner). With my old diff, the inside would have spun or lost grip but not so with the new diff. It felt great!

My friend Lee was having problems with his brakes so I drove his car Sunday morning during warmup to see what I thought. He has a new Quaife and it also felt great so I think my old unit was damaged.

The other thing I did was install a new 5 Star lexan windshield since my old one was getting pitted and hard to see through. I'm really impressed with the 5 Star product. This time I used both of my inner supports to keep the glass from flexing at high speed.

RichieRichZ06

Glad to hear the new diff is working well, but sorry to hear about the oil pressure issue. At least it wasn't something major, like an internal engine issue causing it.

Congrats on the lap record, it seems like you are doing that at every track you've raced at in the last year. Looking at the video, the car does seem to do whatever you want it to.

redtopz

Thanks Rich. One nice thing about my AIM dash is I have data for oil pressure, temp, rpm, throttle position, etc. So I looked at my data last night more closely and can see exactly when and where my belt fell off the tensioner. It happened in the sweeper during my 3rd lap. The worst case for oil pressure was 10 psi at full throttle and 6400 rpm. That happened twice for maybe 5 seconds each time. So maybe my engine is fine? Seems like it would take more than that to kill bearings.

Comparing my Buttonwillow vids to my older vids from last year, it looks like my shifter is moving a lot. So maybe I have loose engine mount bolts also. My plan right now is to remove the tranny and clutch and take a look at the pilot bearing, engine mounts, and rear main seal. Then wait for the Blackstone oil analysis before pulling the engine. I'm hoping the clunking noise I was hearing yesterday was something to do with the pilot bearing and that the engine is fine.

jimtway

It was great seeing the gang again after what seems to have been an eternity, but only a year. I think back on that weekend and all I remember was tracing wires and electrical connections. Can't wait to get ahead of the curve and start dialing this new car in. We are getting the ST-2 tune sorted out this Saturday, so we'll have plenty of time to get the rest of the car tuned up for ACS in 3 weeks. I really hope your engine is ok. Can't wait to battle again on the Roval!

PS. The 1:46 looked way to easy. Next time, drop a couple of wheels or something and make it look harder.

redtopz

Well at least your car is coming together well now. I expect 100% at Cal Speedway . Lee showed me these plug wires and I just picked up a set. They are awesome! I have 2 plug wires that contact the headers no matter what I do. These Accel plug wires are ceramic coated with 45 degree bends so they easily clear. And they are longer than stock if you have custom valve covers and need longer wires. Highly recommended.

http://www.summitracing.com/parts/acc-9065c/overview/

Robert R1

Congrats on the fast lap! One day i'll make it out to BW. It used to my favorite out of the 3 on a bike so I"m sure it'll be fun in a car also.

Sucks about the mechanical. At least you get 2 races per weekend though.

redtopz

Yeah, I like Buttonwillow. It's a fun track with lots of different configs. I guess I was lucky to have both of my mechanical failures in the last race on Sunday instead of the warmup on Saturday.

Update on my car:

Yes, my motor mounts were loose. I'm going to remove the solid aluminum motor mounts and go with poly-urethane mounts front and back to relieve some stress on the drivetrain and help absorb some vibration. Yes, my rear main seal was leaking but my pilot bearing was fine. Once the dry sump stopped pulling a vacuum on the engine it's likely the crankcase pressure built up and blew out the seal. Ryan at Synergy thought this was likely.

So I ended up pulling my engine and taking it to Synergy before getting my oil sample analyzed because I figured it was likely I had some damage. The sound I was hearing was not from the pilot bearing so I figured it had to be from the engine. I did send an oil sample to Blackstone and received the results this morning.

It says the lead content is 5-6 times higher than normal indicating bearing wear. Then I also heard from Rick this morning and he's already torn the engine down and found significant bearing damage but no damage to the major components. So I'm glad I took the engine out before things got worse. This was the first time I've used Blackstone, but I plan to use them several times a year now to monitor my oil and engine.

Robert R1

Bill,

You might want to black out your personal info on that page.

redtopz

Thanks didn't see that.

redtopz

Well it looks like my LS6 days are over . Goodbye LS6, you've been good to me over the past 8 years. I've had 5 LS6's in 2 different race cars. But now it's time to move on to a LS2. Rick's machinist said my LS6 had more damage than expected and it would be best to start over since that engine has already been rebuilt once. It was my original block from my 2004 C5Z. So Rick has a LS2 short block in his shop and we are going to build on that and use my existing heads and LS6 intake manifold/TB. The other option was going with a crate LS3, but that involves more adapter harnesses to work with a C5 and I'd prefer to keep it simple.

In addition, I think the LS2 will be a good platform for SCCA if I decide to return next year in GT2. A built LS2 is treated the same as a stock LS3 per the rules (ie. same car weight and restrictor size). And I'm betting Rick can build a custom LS2 better than a crate LS3 . Funny thing is SCCA made me run a 5 mm smaller restrictor plate with my LS6 engine than they require for the LS2 and LS3... My car is going to scream in GT2 trim.

I'm looking forward to getting this engine back in the car and seeing what more torque and hp feels like. We are putting on some ported LS6 heads that I had in my shop so I'm guessing it will make probably 40 more hp than the previous LS6 unrestricted and quite a bit more power in the midrange with the additional torque down low.

Our next WeST2 race weekend is coming up next weekend so I'll have to miss that one. But I'll have the car back in action for our June race at Sonoma. For ST2 I will still restrict the engine to make about 385 whp.

folsomlarry

Good luck with the new engine Sounds like a better combination for SCCA.

redtopz

Thanks Larry. It will be nice to have the extra mid-range power even in ST2. I can't wait to get back out there again!

folsomlarry

Mid range power is great Our new engine has 3 less hp, but picked up 50 lbs of torque. Makes it a lot more fun to drive.

redtopz

Well I picked up the built LS2 from Rick a couple weeks ago and reinstalled it.



This time I decided to go with poly motor mounts from Hinson and back to the Pfadt poly trans/diff mount. My previous setup was solid aluminum in front and stock in back. I didn't like that setup because the rear could flex and the front couldn't so it places a lot of stress on the drivetrain. Also the solid motor mounts provide no vibration damping so fasteners were tending to back out and get loose (for example my dry sump pulley among other things). I also bought some nordlock kits and have been using them along with loctite to keep all my fasteners tight.

I also decided to replace the stock PS high pressure line with a braided line using AN fittings. However, what I learned in my first 2 laps on track is that the standard AN fittings are not sufficient for PS pressures and will leak. I had to go back to the stock line. The only way to run a braided steel line with AN fittings is to have the hose crimped to the fittings at a hydraulic shop. You want them to handle a minimum of 1500 psi.

redtopz

After installing the engine and getting everything hooked back up, Rick at Synergy managed to squeeze me in for a tune last Weds afternoon. The LS2 is very similar to the LS6 in peak power making about 5 hp more unrestricted, but it makes about 20-25 more ft-lbs of torque all through the mid range. This was noticeable on track . My 60 mm restricted tune has about the same torque as my previous unrestricted LS6 engine. Looking at my data from Sonoma, my trap speeds were identical (which makes sense at the same 8 lbs/hp), but I felt like I had an easier time grunting the car out of corners and making passes in traffic with the extra torque. The limitation on this engine now is the stock LS6 throttle body and manifold, but for ST2 it makes no difference.

On Friday I intended to test the car, shake down the new engine, and get it dialed in for the race weekend. But unfortunately I spent the whole day fixing my leaking PS line. Thanks to Rich at Abel for stocking all the parts I needed since I didn't bring my spares. It's also nice racing with a bunch of other C5 guys who have spares when needed.

On Saturday I went out in the morning just to shake down the car and make sure the engine maintained good oil pressure and that nothing weird happened after my complete tear down and rebuild. Everything seemed good. I went out in qualifying on my Buttonwillow scrubs and put down a pretty good lap in traffic. Those tires felt good. Then for the afternoon race I mounted a new set of A7's all around. This was my first time with A7's in front. I should have scrubbed them in because I ended up overcooking them on the first heat cycle which makes them greasy and they never have good grip after that. I ran the same tires on Sunday and here is that race. Group C in Norcal is the same as ever with way too many classes of cars piled together. We had a pretty solid group of ST2 cars, 3 from Norcal, 3 from Socal, and 1 from WA. All of them good drivers but some without much time on this track. The bmw from WA had won nationals in ST3 at Sonoma last year and GTS4 at Miller the year before. He and his car are very fast and it took all I had in traffic to take the win on Sunday. I came in 2nd on Saturday.



The best news is that my new engine and all other components ran well. Put the car back on the lift yesterday and nothing is loose or leaking. That's a good sign that the motor and diff mounts were the right choice.

RichieRichZ06

Congrats on the win Sunday. I watched that video last night from your FB post. I was damn near yelling at my computer for those cars to get out of your way. That was a lot of traffic and I would be scared to death being in a Legends car with you guys on track also. Your speeds compared to theirs is a significant difference.

redtopz

Yeah, it's definitely nice being in the passing car where you have more control. One more month until NASA west nationals at Laguna Seca. We should have a large turnout in ST2 with around 15 cars this year.

redtopz

Last year I swapped out my stock rear brake rotors for the Essex AP Racing endurance setup. It has been the best thing I did for my brakes. Until today! I met some of the Essex guys at the Runoffs last year and we have been planning to get their new AP Pro5000 brake kit on the front of my car. When I bought the car in 2010 it had a Stoptech front brake setup with several years on it. It has been a reliable setup, but it's getting long in the tooth with probably 10 years of hard racing and time trialing on it.




With the NASA West Championships coming up next weekend, I am happy to have this new AP kit to install. The kit is professionally packaged and includes detailed instructions for the corvette. These will work on any C5 or C6, not sure about C7. It includes rotors, hats, calipers, brackets, SS lines, nuts and bolts. Everything is included. The AP calipers are much lighter than the stoptechs and have a better design. The rotors weigh about the same which is good because they need mass to take the punishment from racing. The rotors have much more cooling vanes than the Stoptechs. It only took me 1 hour to remove my old setup and install the new one. The fit is perfect. With some kits you have to grind or shim the brackets or knuckles to make things work. Not this kit. It is perfect.

A huge plus is the pads are cheaper for this setup than the stoptechs or even stock calipers.








Thanks Jeff and all the guys at Essex for putting together this package for corvette racers and track rats. It is the best thing out there for our cars that I've seen and I'm looking forward to providing some performance feedback next weekend from Laguna Seca which is brutal on brakes.

redtopz

I spent the past couple days (actually only 2 track sessions over 2 days ) shaking down the car and trying to get it ready for Laguna Seca next weekend. MCE dyno was at Laguna Seca which is less than 2 hours from my shop so I went down there Friday and Saturday for the scca regionals. I needed to get on the dynojet before nationals to get my classification forms done with this new engine. The only problem with my new Synergy LS2 is it makes too much power!

Even with Rick detuning it by cutting timing and adding fuel, my 3" air inlet pipe and small air filter, and a 60 mm flat plate restrictor it is still making 393 whp and 403 ft-lbs of torque. This thing will be a beast unrestricted and tuned for power. So I'm going to need to run a little heavy this year, but with the extra torque that my LS6 didn't have I don't expect it to be a problem.

The car is running very well overall, but I'm having a difficult time getting my tranny to shift from 2nd to 3rd. It's a new tranny and my first weekend in it was the Buttonwillow ST2 race. I noticed it then, but figured it must just be me rushing the shift or missing the right spot. But it's been an issue every weekend since and over the past 2 days started getting really bad grinding almost every time. So unfortunately with only 4 days to go I have to remove it and either fix it or install my old tranny with shorter gears. Rich at Abel is going to get the tranny torn apart tomorrow and see if the synchros or shift forks look bad and then we'll make a call. It's great having a team of pros helping me out like this. Rich at Abel, Rick at Synergy, and Tony at TC Design are always there to help in a crunch and I appreciate it!