BUILD THREAD 86 GP 2+2~Blown 6.0

[81cutlass]

Ok so I did remeasure the rear suspension angles last night to get a formally correct instant center calculation.

I have spent the last few days reading and drawing free body diagrams in my brain to solve my my lousy launch. Yellowbullet, although a colorful place and dead these days, still has the best archive for drag racing.

This is where my car sits today. Honestly the AntiSquat value in % makes no sense to my engineering brain (what is it in relation to? Not sure, seems like a made up number unless they show the equation) but essentially the consensus on YB is that the antisquat needs to be between 100% and 130%. Anymore than 130 and you need a REALLY good shock.

I have 33%. That means the rear suspension is pulling the body down and essentially unloading the rear tire from the track.

My best bet is to lower the hole on the rear housing 2.5". It has a reasonable 110% antisquat value if I do.

I could raise the diff side UCA pickup point or lower the chassis side UCA mount but that is a lot more invasive and more for a 1000hp grudge car where you want 130% antisquat and have good shocks to control.

 

[81cutlass]

Got time to get the lca drop brackets in.

I started drawing them up last weekend and cut one of them out early this week but my bandsaw blade snapped and I need to get a replacement.

These lower the lca 2.5" which should get my instant center set up so the car doesn't squat.

I also had a bit of driveline vibration and checked my pinion angle and it was a bit funky. Up 2.5 degrees. With my uca bushing slop problem solved the rear doesn't move as much (good) and I had it set to be ok when it had slop to one direction but it went really bad when it took the slack out on the other side.

The trans is angled down 6 and the driveshaft is down 1.5, and the rear is now at zero, when it was up 2.5. The set your pinion angle guides says this is wrong but it doesn't shake anymore so I'm claiming a win.

Took the thing on a 40 mile round trip to the night cruise for the first time this year and it stayed cool so my fan fuse up size worked.

I've gotta convince myself to buy expensive adjustable rear shocks now...

 

[81cutlass]

I sold models and justified finally buying adjustable rear shocks.

Hopefully that will control my launch a bit.

 

[64nailhead]

No more cheap for you!

I want a set of those in the worse way. Are you going to get them anytime this year lol?

 

[81cutlass]

No more cheap for you!

I want a set of those in the worse way. Are you going to get them anytime this year lol?

Yeah I have done enough reading online where people say you WON'T get a drag radial to work unless you have adjustable shocks. Maybe that applies to 8 second cars on a trans brake and although I am a long way off only in the low 11's, it's not like I am in the 14's either. I've ate enough driveline parts that maybe these will be an insurance policy. Fingers crossed. I'm a tight-arse on a lot of stuff but I don't know how to hack together adjustable shocks lol.

I hope they show up this week! They are claimed to be in stock and Trick chassis is only 3 hours away from me.

Ironically the Viking factory is like 40 minutes away from me but ordering from Trick got me to save $25 in tax alone. If I bought them in state from my dealer buddy they'd have to charge sales tax. So yeah, it was cheaper to pay shipping and not get a buddy discount than to pay tax lol.

May 1st (yeah, this Saturday) the nearest 1/4 mile track opens. If I can get my poop in a group and get these shocks installed my goal is to head to the track. The rest of my May is full of family/friend events so its going to be mid June before I'd get to the track otherwise.

If my shocks don't show up the local LS club is doing a cruise thing I might hit up.

 

[Northernregal]

I have vikings to go on the Cutlass, thats a solid buy for shocks.

 

[81cutlass]

Well as everything is out of stock these days I wasn't surprised when I didn't get a shipping notification on the shocks. Got a cryptic email for a backordered part (tuned out it was the replacement crisper drawer for the fridge) and called Trick to see if it was them. It wasn't, but they are out of stock.

Trick placed a restock order 2 weeks ago and they usually come in 3 weeks so *hopefully* they will be on the way to me next week. We will see.

That seals the decision making process for this weekend. Guess I am going on the cruise and not to the track. Guess it's going to be June before I see if the car can go 10's.

 

[motorheadmike]

Well as everything is out of stock these days I wasn't surprised when I didn't get a shipping notification on the shocks. Got a cryptic email for a backordered part (tuned out it was the replacement crisper drawer for the fridge) and called Trick to see if it was them. It wasn't, but they are out of stock.

Trick placed a restock order 2 weeks ago and they usually come in 3 weeks so *hopefully* they will be on the way to me next week. We will see.

That seals the decision making process for this weekend. Guess I am going on the cruise and not to the track. Guess it's going to be June before I see if the car can go 10's.

Sh*t happens. I am 6 weeks waiting for a part from Summit now. Got the tracking number yesterday and it hasn't moved yet. The last year has been a frigging joke... first world problems I suppose.

You could just build your own.

 

[64nailhead]

Steel, welder, caulk and duct tape - I have them all in stock. Personally, I'm good.
.
. 😁

 

[64nailhead]

That is a good job on those lower control arm mounts. I LIKE IT!!