Cascade Crew

[QwkTrip]

Hopefully this will make the engine the bruiser it was supposed to be. Also got upgraded rocker trunions that I will install at same time.

[QwkTrip]

I think my traction issues are excessive. It should be hooking better than it does. Got under the car tonight and measured some things.

A) Passenger side rear lower control arm is at 0 degree angle, and the driver side lower control arm is at 2 degrees, sloping down toward the axle. It does seem appropriate to drop both arms to the next lower hole, don't you think?

B) I measured the rear axle pinion angle and found it to be at +3 degrees. My results were,

Driveshaft angle: 0 degrees
Pinion angle: +3 degrees (sloping upward toward front of car, as measured on the torque arm pad)

Shouldn't the pinion angle be at -2 degrees relative to driveshaft? Or do I need to take into account the angle of the transmission yoke too? I have never dealt with pinion and driveshaft angles so not quite sure what I'm aiming for. But I think driveshaft angle does have an effect on traction, does it not?

Yes, I could spend the next few weeks reading about this and learning on my own but this site needs an injection of activity so somebody please lecture on the topic.

[QwkTrip]

I am getting the idea that setting pinion angle to -2 is old wives tale derived from the old muscle car days when pinions climbed a lot on launch with leaf spring suspensions.

Torque arm suspension does a much better job controlling pinion climb and I don't need to compensate hardly at all for pinion climb, especially with my chassis mounted torque arm with solid joints. Just set equal and opposite angles (trans and pinion) to manage vibration and then call it a day.

[Dewey316]

Yeah, i always felt -2* was a bit much unless you had a car that really launched hard and had really sticky tires. You might do a it a tick negative, like -0.5* or so, just to account for any slack that is there to be picked up, and call it a day.

Your LCA's being slightly negative should be good, if you go too far lower at the axle side, you can get roll-steer doing weird things for handling and really risk brake hop problems, especially with your shorter torque arm, since your instant center is already moved back. I tend to prefer them pretty close to level.

Here are the important things. What you gain by dropping the LCA's is slight rise of the instant center, this effects the angle theta (as shown below). and since your TA is shorter, the effect is larger, but that angle is already much larger than a stock TA would create, really the angle of the LCA's doesn't do all that much but tweak the A/S a bit for most people.

Also remember, that every bit of anti-squat you dial in, you end up with the opposite reaction under braking. Cars with crazy anti-squat numbers almost always tend to have brake hop issues if you have normal levels of rear brake bias.

[Dewey316]

I should also add one more really big thing here. To much anti-squat has negative traction effects to a point, especially on a manual trans car. Since the torque loading actually has a spike early, pushing the rear of the car up, once the torque applied starts to tail off, the suspension will naturally want to unload, which hurts you.

If you notice the car initially bite, lift the rear, then try to sit down a little bit, and THEN it loses traction, you might be experiencing that happening. IF that is happening, you need to actually take some anti-squat out, so that the effects of that are lowered. Just thought I would add that point, because traction isn't as easy as just always adding more A/S.

[QwkTrip]

I don't think the rear squats at all. But frankly my car is sprung so stiff that I couldn't tell you what the rear suspension is doing. And the front barely moves either. Huge sway bars + rock hard springs.

Car is way over sprung in an effort to keep that damn torque arm from smashing into the ground. I was just chatting with a co-worker who followed me home the other day and his observations made me realize I need to change my setup and stop trying to make it work. It's not ever going to be what I want. That UMI torque arm has terrible ground clearance for a street car. I'm going to change things up and make the car work the way I want - both traction and ride quality.

[QwkTrip]

I'll tell ya, I'm getting sick of these brakes. I drove the car out of the garage today and no brakes. I have NEVER had so many problems with brakes. This is just fricking ridiculous!!!

[QwkTrip]

The SSBC proportioning valve failed. The fluid reservoir is drained and all that fluid has doused the paint and wiring on the frame rail.

I made a lot of phone calls today and started planning out Brakes Part Deux.

[QwkTrip]

If anybody has a 1LE prop valve to sell then I am interested. Thanks.

[Twilightoptics]

How did it fail? I've used DOZENS of those SSBC valves on customer cars without a single hitch.

[aaron_sK]

Installing any GM valve is a step backwards IMO. Buy a Wilwood or a new SSBC and you're down the road.

[QwkTrip]

Since the car is just sitting a while waiting for brake parts, I started the cam swap.

One side of me is a little afraid that I just went from "driver" back to "project car" but I'll keep this moving along okay, I think.

[QwkTrip]

The rocker arm bolts use an 8 mm socket which is way too small for the break-away torque to loosen the bolts. I broke two Craftsman sockets trying the get the bolts out, and one of the rocker arm bolts was particularly difficult and the head was beginning to strip. I went down to Autozone, of all places, and found a thick-wall socket. That was just enough to get that last bolt out. Fortunately, the rocker trunion upgrade kit comes with new bolts so I won't be reusing the original bolts!

[Twilightoptics]

That's one thing the big tool branda have going. Their tools distort way less and don't have to be as thick. Craftsman is great for home projects but anything more and it's really just cheap. They've killed their qc like most things.

[chevymad]

Craftsman has gone to complete crap. I used to use them when I started working years ago and they were fine. But as they wore out and needed replacements the replacements lasted no time at all. Better off buying Harbor Freight most of the time. Napa has switched to Carlysle now. Some of their stuff is ok, their screwdrivers seem to hold up decent, but I wear their sockets out in no time.

My snapon guy quit coming after I bought a Costco tool box. But I've been buying ALOT of Mac stuff last couple years. I don't think their tool is quite as nice but pricing is better.

[QwkTrip]

I've had a heck of a day, both good and bad. Did everything right, blocked the lifters, got the old cam out okay, and then a damn lifter fell when I put the new cam in. I guess my lifter block was too small and the lifter squirmed by and fell down. So.... I'm pulling oil pan and a head and now into a lot more work than I ever wanted. Head is on the floor tonight and next I have to fish the lifter out of the engine.

What can be good about this, you say? Well, with the head off I got a chance to measure the true displacement of the engine and it is in fact a 4.06" bore making it a 427. And the pistons are already fly cut too. Somehow I got an iron 6.2L block, or it was machined. Either way, I'm glad I have the larger bore because nothing should be holding back power now. Hopefully this thing will sing a new number on the dyno when it is all back together.

[QwkTrip]

Old cam is definitely a Thunder Racing TRx V.2

And this is not a low compression engine. Pistons are very slightly proud of the deck. Compression ratio is a good 11:1 by my estimates.

[QwkTrip]

This....




Caused all that. And it was no lack of talent to fish that thing out of the engine either. Lots of handy work with multiple magnet rods while working blind and rotating the crank. Like solving a puzzle.

[Twilightoptics]

I don't have much LS experience: you can pull a head without pulling the intake?!

[QwkTrip]

No, the intake is sitting on a 2x4. I didn't want to disconnect the fuel line.