My 1985 Monte Carlo SS Barney...

[Tomswheels]

Travel Safe Lance, looking forward to finally seeing it in person Tuesday at the Nats!

[SSLance]

Same to you Tom, although my 3 hour trip to Lincoln should be a drop in the bucket compared to your trip...

While under the car I noticed the start of a valve cover leak, once back up top I put a allen wrench on my centerbolt valve covers...all 4 of them on each side not even finger tight...

WTF is it with all of the cap head bolts on my car coming loose anyway? The hex head bolts holding all the important stuff on the car seem to be staying tight with no issues.

[SSLance]

So an old mechanical issue reared it's ugly head again at the SCCA Nationals. It took me a while to diagnose exactly what it was, it actually started at CAM East month or so ago. I initially thought it was the clutch posi giving up again as it seemed like the car was spinning the inside rear tire on exits from short sharper turns. The more I drove it and the more it happened, I finally figured out the clutch was slipping, not the diff.

If you listen close during these runs, on the exit of some corners you'll hear the RPMs spike up but the car doesn't move nor do the tires spin, that's the clutch slipping.

https://youtu.be/Mvs9OZX5Kpw

It hurt my times on the big long fast courses at Lincoln so I did not finish well in either event. The car cornered fantastic, much better than I thought it would...it just wouldn't handle down the fast straights. Time to come up with a new game plan. This clutch is a RAM rated at 500 hp I think that is just over a year old...and I'm making no where near that kind of power.

[alwaysracin]

Do you have problem during the Cam Challenge? I do not have good cell reception to watch the videos.

Does it only happen during corners?


Had to edit. I was able to watch the video. That is the rear differential. Easy way to test. Take an on ramp or somewhere you can make the tire spin under hard cornering. Go home. Disconnect rear sway bar and if adjustible add front bar. Retest. I personally would do this while using petrel data ' s solostorm to show g loading. Then adjust balance without the rear bar or another way. You could change the diff but I don't want to see you waste money on a clutch you don't need.


Scott Fraser

[SSLance]

Scott, watch this video... 32 seconds in it spikes RPMS and you can hear it spin the tires. At 51 seconds and 108 seconds you can hear the RPM spike worse for a longer time...and no tire spin noise.



I had this exact same symptom happening before I replaced the original clutch middle of last season and the new clutch fixed it immediately. I picked up 2-3 seconds on my close competitors at our local events just by replacing the clutch. It was like going from a torque converter to a direct connection. It is strange because under just about any other circumstance the clutch hooks up fine and gives no sign of slipping at all...just like the original clutch I replaced.

At 2:08 into this video is the worst episode on this side, but with speakers turned way up I can pick up several other times it spikes RPM without spinning the tires as well. It's not a total failure of the clutch grip, it just slips some as the power is applied and eventually hooks back up.



It started early August in Peru...after a ton of runs on the grippy concrete. Sunday morning out there it showed up in earnest. It's done it ever since just in certain circumstances though...when I really needed to put the power down.

[alwaysracin]

It looks to me like you have tire spin on hard right corners.

Before you spend money and time, I would really want to test everything i could.

I am sure you can test break away torque. You can also check to see if you have less tire spin by testing. Take an on ramp or somewhere you can make the tire spin under hard cornering. Go home. Disconnect rear sway bar and if adjustible, add front bar. Retest. I personally would do this while using petrel data's solostorm to show g loading.


Good luck,
Scott Fraser

[SSninja]

Well-deserved write up on Barney: http://bangshift.com/bangshiftapex/a...arving-g-body/

[SSLance]

While I haven't had time to touch the car since coming home from Nationals, Dave Nutting has been busy working with it...as seen above.

Thanks for the pics and article Dave, you did a great job shining up this turd!

[SSLance]

Video from today, best examples of clutch slip are at 40 and 49 seconds...



Rear sway bar was disconnected on the driver side and the rear shock rebound was at -7 clicks from full stiff. It still lifted the driver side rear tire twice that I saw which made the pass side rear tire shudder. Still very driveable though, not edgy at all. Not sure what corner exit grip would have been like because every time I was hard on the gas corner exit it would slip the clutch. Rear rolled over a bit more than normal with the rear bar disconnected but really wasn't even that noticeable. I got used to it very quickly.

[alwaysracin]

Looks like the rear tire is staying down a little better. I want to say I do hear the engine having a little free reving, ok you are right. One other test before throwing in a clutch (yes, I am a lazy or want complete verification before replacing parts mechanic), on the freeway clutch kick it and see if it locks up or spins the clutch.

I did notice the LR tire come up in the air at 20 and 28 seconds. Leave the rear bar off, add rear spring to add stiffness and make for quick transition without loosing inner tire grip by lifting the tire. I am wondering if the chatter is push and the front tire rolling over from too much angle. It would be interesting to actually see steering input and what the car does. I like using something like this.
https://www.youtube.com/watch?v=4_9_YF-gSNI

try the clutch kick for the test of the clutch but you almost have me sold on needing a clutch.

Scott Fraser

[SSLance]

Yep I'm 100% convinced it's the clutch now, glad I could help convince you too. ;)

The chatter is definitely on the rear outside tire and it happens when the inside tire just briefly lifts. I agree on the less or no bar on the rear and more spring rate on the rear...but to be honest, it's still a street car too and I'm not that crazy about the idea of putting more spring in the rear. It's right on the edge now of a smooth street ride and getting a little harsh on small bumps at slow speed. I know I could swap in stiffer springs for a race then swap them back out for daily driving but not sure I'd do that vs put up with a little bit of chatter once a month or so.

The car can carry a ton of speed in turns now and is not edgy at all, I like it as it is. It'll get even faster with a good clutch and a gear type posi in the rear.

It still finished 19th in raw time out of 120 cars yesterday...even with all of it's ills. Not too dang shabby really for what it is.

http://www.kcrscca.org/results/solo/...vent11_raw.htm

[SSLance]

Here are a couple of my other runs from another perspective.



Man that was a fun course!

[alwaysracin]

Ok, this video gives me a better idea of what the car is actually doing. I can see the front and rear tires. I can also see the car pushes, which makes sense with now running without a rear bar. I also see that when really cranking in big steering angles the tire really rolls. I have experienced when the tire rolls too much it shakes the car. Does anyone have photos from outside the car? I study and hunt for every photo I can find.

Let's look at this. The car pushes. It looks like a steady state push which will effect everything. I always try to add grip. Are you running Falkens? What is your camber? How much rake?

Ok, I understand the street car thing. So let's look at this a different way. Are your shocks adjustable, how many ways? You can make a compromise of course it will not be the best of either worlds but it can still work.


Scott Fraser

[SSLance]

So a new phase of upgrades has officially started. I finally decided to crack the seal on the crate engine and upgrade the heads and cam in an effort to keep up with the LS powered cars I race against on the straights. I plan on doing more road course events from now on and less autoocross so this was a necessary upgrade and actually makes more sense than upgrading the rear suspension, wheels and tires just to try to keep up with all of the autocross specific CAM cars coming out of the woodwork.

I picked up the top end from a blown up 604 crate engine from a local racer, a set of worked over fastburn heads, 1.5 roller rockers, the 604 cam and a single plane intake. I had our local speed shop do a valve job on the heads since a few of the valves had been hit, ended up replacing three of them, all of the springs were checked and all of the valves were lapped in again.

I'm going to custom order a cam Monday to meet my needs and will reuse my dual plane intake, Q-jet, and MSD and just about everything else. Only thing I'm really swapping out is the heads and cam...but those alone should bump me about 100 hp in all the right spots with only giving up just a scant bit of torque way down low (built in traction control).

So we started today by pulling the transmission and then the engine. Only took about 2 hours to get the trans out, then we inspected the clutch a bit...took some time to loosen up a few things underside...then lowered the car to start under the hood.



The flywheel side wasn't too bad



The pressure plate side was toast though





The flywheel surface is okay, the pressure plate surface has some small ridges in and burn spots on it...so it looks like a whole clutch kit is in order.

This was taken when we stopped for lunch.



About an hour later...





These plugs have been in this engine since my "electric fan upgrade" 5 years ago now. Interesting to look at them and the corresponding header ports.

[SSLance]

In the next day or so I'll start to tear this apart...



and get ready to put these heads to good use.







Purple and yellow is my current engine, Dark blue and Green is what we are shooting for power wise and lite blue and red are a stock LS2 like I'll be racing against.

[nokones]

The first CAM event is at California Speedway at the end of April. Are you going to have everything done in time and make the event?

[SSLance]

It shouldn't take me more than a couple of weeks to get everything back together...depending on a few parts, but I don't plan on making it all the way out to CA for that event. That's a LONG haul for me...

[SicMonte]

nice upgrades!!! Looking good!

[Jimbo1367]

This car is bagging for a LS3.

[KSScotton]

Lance - don't make Barney too much faster! I was just starting to catch up with you ;-)

Jeremy