Project SicMonte

[carguykeith]

I'm doing the 8.5 as follows: Welding the axle tubes, UMI Performance Roto Joint bushings, Moser 30 spline axles, Tru-Trac, Yukon 3.73 ring and pinion, aluminum diff cover, Baer SS4 brakes....not sure about the yoke though.

Thats pretty much how I built mine, except I wanted c-clip eliminators too so went with THIS and different brakes.

I would definitely upgrade the yoke, I think it was only $75 or $100 to go to a steal 1350 yoke instead of the cast 1330 that was on there stock.



Oh one more thing to think about is the lower control arm mounts should be lowered if your ride hight is more than 2" below stock, UMI has nice weld on brackets for it, that's what I'm using. My build thread (link in my signature) is only a couple of pages and has more details if you're interested.

[SicMonte]

I left the 3.42's in mine since I don't have OD yet. Plus with short 245/50/16 tires I'm spinning pretty good on the highway... Still planning on making it to the Syracuse Nationals? I'll have my car there!

I'll be at the Syracuse Nats working the autox with the ASCS. My car will not be there though.

[SicMonte]

Really wish they made swaybars for my car - I just discovered they made coilovers for the C5+.

...and your life is now changed forever.

[SicMonte]

Thats pretty much how I built mine, except I wanted c-clip eliminators too so went with THIS and different brakes.

I would definitely upgrade the yoke, I think it was only $75 or $100 to go to a steal 1350 yoke instead of the cast 1330 that was on there stock.

Oh one more thing to think about is the lower control arm mounts should be lowered if your ride hight is more than 2" below stock, UMI has nice weld on brackets for it, that's what I'm using. My build thread (link in my signature) is only a couple of pages and has more details if you're interested.

Ok...mind blown.


Tell me more about this yoke you speak of.......

Tell me and explain to me more about the c clip eliminators.....

Tell me more about why you wanted those brackets? I've heard good and bad about them......

[carguykeith]

Ok...mind blown.


Tell me more about this yoke you speak of.......

Tell me and explain to me more about the c clip eliminators.....

Tell me more about why you wanted those brackets? I've heard good and bad about them......

On the yoke, ok I was wrong on two things; 1. the stock cast unit is a 1310 u-joint not a 1330 so REALLY needs swapped and 2. a steel one is $125 HERE or a cast one is $65 HERE I must have gotten mine on sale or eBay or something...

C-clip eliminators do a couple of things but the only one that really matters since you are looking at rear disks with floating calipers is that it's required on 1/4 tracks if you're faster than 10.99. If you never plan to put at least a 6-point cage in your car you can skip this, since you're limited to 11.49 w/o the cage.

I know way less about 4-link rear suspension calculation than I should but it's generally agreed that the anti-squat goes too low if you don't move the LCA rear mounting locations when you lower the rear. I did everything at once so I can't say for certain it was the relocation brackets but I can say I hooked up MUCH harder afterwards. Someone like Marcus at SC&C could explain the actual specifics. I really do need to get off my ass and learn 4-link calculations... Worst case is you waste $75 and an hour of your time installing the brackets but decide you like the factory location best.

The good news is an 8.5 10-bolt with a decent carrier, 30 splines, welded tubes and a AL girdled cover is good to an easy 800hp so you shouldn't ever need another rear once you're done.

[Norm Peterson]

I think the bigger problem with lowering the rear of an OE-triangulated-4-link P-T car and not correcting the LCA inclination is with respect to axle roll steer - I can see that going from something like 8%, maybe 10% in the vehicle understeer sense (which is too much for a car used at autocross as it is) out to somewhere beyond 20%. 0% would define this effect to have neither understeer nor oversteer consequences. Although setting axle steer to be ever so slightly loose (vehicle oversteer, negative percentages here) for autocross might help that activity, it would tend to feel 'nervous' and too demanding on either the street or out on a big track . . . so you'd probably want axle steer to be under 5% and probably closer to 3%, but not any negative value.


Norm

[SicMonte]

On the yoke, ok I was wrong on two things; 1. the stock cast unit is a 1310 u-joint not a 1330 so REALLY needs swapped and 2. a steel one is $125 HERE or a cast one is $65 HERE I must have gotten mine on sale or eBay or something...

C-clip eliminators do a couple of things but the only one that really matters since you are looking at rear disks with floating calipers is that it's required on 1/4 tracks if you're faster than 10.99. If you never plan to put at least a 6-point cage in your car you can skip this, since you're limited to 11.49 w/o the cage.

I know way less about 4-link rear suspension calculation than I should but it's generally agreed that the anti-squat goes too low if you don't move the LCA rear mounting locations when you lower the rear. I did everything at once so I can't say for certain it was the relocation brackets but I can say I hooked up MUCH harder afterwards. Someone like Marcus at SC&C could explain the actual specifics. I really do need to get off my ass and learn 4-link calculations... Worst case is you waste $75 and an hour of your time installing the brackets but decide you like the factory location best.

The good news is an 8.5 10-bolt with a decent carrier, 30 splines, welded tubes and a AL girdled cover is good to an easy 800hp so you shouldn't ever need another rear once you're done.

the yoke you put a link to is a 12 bolt. ??

[carguykeith]

the yoke you put a link to is a 12 bolt. ??

Oops, too many tabs open copied the wrong one for the steel yoke...

Still $120 HERE for a steel one that fits the 8.5 10 bolt.

You have a drive line loop right? All this talk of u-joints reminded me of those youtube videos, if you don't have one get one NOW.

[SicMonte]

Oops, too many tabs open copied the wrong one for the steel yoke...

Still $120 HERE for a steel one that fits the 8.5 10 bolt.

You have a drive line loop right? All this talk of u-joints reminded me of those youtube videos, if you don't have one get one NOW.

oh I've had one of those for years!

is there a difference from the Moser vs Strange vs Inland Empire yokes?

[SicMonte]

Got my Centerforce Dual Friction clutch in and my balanced flywheel!!!

Thanks to Centerforce for all their help with this project!!! This clutch is a piece of artwork!!!!






Car is missing a lot of stuff now...time to get to work!!!!

[carguykeith]

oh I've had one of those for years!

is there a difference from the Moser vs Strange vs Inland Empire yokes?

Glad to hear it!

Not as far as I am concerned, just the cast vs steel is all I would worry about. I don't think I've heard of anyone busting any steel 1350 yoke at least at the power levels we are talking about.

[SicMonte]

oh I've had one of those for years!

is there a difference from the Moser vs Strange vs Inland Empire yokes?

Glad to hear it!

Not as far as I am concerned, just the cast vs steel is all I would worry about. I don't think I've heard of anyone busting any steel 1350 yoke at least at the power levels we are talking about.

Thanks so much for the info and insight!

I pulled the trigger last night and had a lil shopping spree at Jegs....

Tru Trac, 30 spline Moser axles, Inland Empire 1350 Yoke and the LPW Ultimate 10 diff cover.

Can't wait to get this rear all done!!!!

[83hurstguy]

While there's no doubt 1350 is the way to go if you can, just for reference, the stock G-body yoke is a 3R. Most GM stuff '78ish and later has that as far as I know. I've heard it's around a 1330 in strength.

I have the 30 spline Mosers in mine, great pieces. Moser did send the incorrect axles twice (kept sending 28 spline), so count them as soon as they show up. As a heads up, be cognizant of the LPW cover to sway bar clearance. The nuts aren't counterbored like the TA cover, so you'll need to have the bar level at ride height or it will hit under bump travel. I just went through hell with a DSE bar as a result. Need to get pics up, just been working stupid hours.

I also had two holes in my 8.5" housing that weren't tapped deep enough for the LPW bolts supplied with the cover, they were bottoming out before torquing cover. LPW sent shorter bolts, I ended up putting ARP's in there anyways.

[carguykeith]

Thanks so much for the info and insight!

I pulled the trigger last night and had a lil shopping spree at Jegs....

Tru Trac, 30 spline Moser axles, Inland Empire 1350 Yoke and the LPW Ultimate 10 diff cover.

Can't wait to get this rear all done!!!!

You bet, always glad to share what I know!

Oh yeah my sway bay was close with the TA cover and doubt the LPW would have fit at all. If it hasn't shipped yet it may be worth swapping covers I was really impressed with the quality of the TA.

[SicMonte]

You bet, always glad to share what I know!

Oh yeah my sway bay was close with the TA cover and doubt the LPW would have fit at all. If it hasn't shipped yet it may be worth swapping covers I was really impressed with the quality of the TA.

damn...I have the TA one on my 7.5.

[BigBlockOlds]

Just curious if you ever found a proportioning valve that worked? I assume so since the car has been out and about.
I ran into an issue earlier today with my '87 while loading it onto a trailer where the brakes gave out on me and I got to roll off the trailer without any brakes. Luckily I was able to jamb the pedal as hard as I could and got it to stop before hitting the house.
I have one of those brass proportioning valves and tried tightening all of the lines going to it but still have a leak. It appears to be coming from the plastic pressure switch. Not sure exactly what I should do here if the majority of these valves are defective. :(

Thanks,

[SicMonte]

Just curious if you ever found a proportioning valve that worked? I assume so since the car has been out and about.
I ran into an issue earlier today with my '87 while loading it onto a trailer where the brakes gave out on me and I got to roll off the trailer without any brakes. Luckily I was able to jamb the pedal as hard as I could and got it to stop before hitting the house.
I have one of those brass proportioning valves and tried tightening all of the lines going to it but still have a leak. It appears to be coming from the plastic pressure switch. Not sure exactly what I should do here if the majority of these valves are defective. :(

Thanks,

After dealing with four leaking aftermarket brass prop valves I bit the bullet and got this Baer adjustable prop valve. It mounts up nicely under the stock master cylinder using a bracket from GNS Performance. A couple lines had to be made and bent but it was sooo worth it. Haven't had an issue since.

[BigBlockOlds]

Are you still running a stock valve on the frame rail for distribution or did you just tee the lines off? I have an aftermarket adjustable proportioning valve inline to my rear brakes after the stock valve.

Thanks,

[SicMonte]

Are you still running a stock valve on the frame rail for distribution or did you just tee the lines off? I have an aftermarket adjustable proportioning valve inline to my rear brakes after the stock valve.

Thanks,

I thought I had a pic of what I did. I just tee'd them off.

[SicMonte]

Been a lil bit since I have updated the progress of the t56 install along with all my new suspension parts....that's bc not much has happened!

here's the new shifter mocked up on the trans to see how it looks and fits.