I've done the LS1 brake upgrade on my car but now can't get the alignment correct. I suspect a bent LS1 spindle. Prior to the install I had no problems getting the car aligned. Anyway, my question is can I cut the ears off my LT1 spindles and use them? Will the LS1 calipers bolt up?

JeffA

 

So no one knows if the LT1 spindles can be modified to work with the LS1 brakes?

JeffA

 

Jeff,
You might try the AutoX section. Bet someone has an answer for you there.

--James

 

I'm sure someone must know, but there are so many threads on LT1 Tech, many folks miss new threads.

The bad news is: I don't believe they can. We have both LT1 and LS1 knuckles(spindles) for a C5 brake upgrade we're working on. I'll compare the knuckles in a day or so if you can wait.

What part of the alignment can't you get correct? toe? camber? caster? One side or both? Knowing that would help diagnose the problem.

 

Thanks for the reply OldSStroker. If you could compare the two I would much appreciate it. I have to work this weekend so I can wait a while. As far as alignment numbers, I should have written them down as I can't remember exactly what we ended up with. Basically I can't match up the caster settings. I had around 4.5 on the left and 5.5 on the right. The only way I could get them that close was by taking the camber to -0.5 or so both sides. I could get a lot more negative camber (my car has the Pro Kit and I want the negative camber for autocross) but the caster split grew worse. I didn't actually do the work but watched the alignment tech. The same shop has done well in the past so I think they are ok. A week before a different shop tried and failed to align the car but I hoped that they just didn't know what they were doing. Anyway, the result is that the car pulls to the side with less caster and I can't get decent negative camber without making things worse. My car aligned fine before the LS1 brake upgrade so I assume the spindles are at fault.

What about the C5 brackets? They adapt a LT1 spindle to accept a C5 caliper correct? If the C5 caliper uses the same mounting locations perhaps I could use a set of C5 brackets on my LT1 spindles for the LS1 calipers? I wish a after-market spindle was available.

JeffA

 

I recently did the LS1 brake upgrade and then went for an alignment:

I asked for:
Caster +4.0
Camber -0.5
Toe 0.0


I got:
Left Right
Camber +4.6 +5.1
Caster -0.2 -0.5
Toe 0.0 0.0

They did spend a fair bit of time trying to even things out but after an hour banging and tinkering they basically said "that's close enough" Sorry for no real answers here but just thought I would share my somewhat similar experience.

Kris

 

Thanks for the input Kris. That’s close to what I have except I have a bit more cross caster. The caster problem is causing a pull to the left at freeway speeds and the lack of negative camber is bad for autocrossing. I could almost deal with it but I've done too much to this car to live with a poor alignment. My main goal is to do better at autocross events. I've got to stay ahead of my friends and their mustangs.

JeffA

 

Now that you mention it I thing I do have a slight pull to the left that I also notice on the Highway. I am planning to get the alighnment done again once I get a new set of tires on (which will be soon) I also seem to remember something along the lines of lowered cars being even more difficult to get closer to ideal "auto x" specs (but I am not expert) As mentioned above there are some real experts in the Autocross forum and if you post there you more likely to get some good feedback.

 

I have posted in the autocross forum but the traffic is much sparser there. A lowered car should be able to get more negative camber, which is good for autocross. Before the LS1 brake swap I was able to get a little more than -1.0 on both sides. Now I have to take all the camber out to get as little cross caster as possible. I'm tempted to get LG's adjustable lower A-arms but don't want to spend that kind of cash.

JeffA

 

I'd highly recommend GW upper A-arms over the LG lower arms. They are under $200 (I skipped the del-a-lum bushings and have had no regrets in the past 3 years of running them) and give you a lot more negative camber without the hassle of the LG install (which is a lot harder than replacing the upper arms). The LGs are also not adjustable on the car (which is extremely impractical when it comes to getting an alignment). With the GW arms, I have about -1.5 or so camber with 1LE springs at slightly ABOVE stock ride height. When my car was lowered an inch, I got -2.5 camber (which was absolutely perfect for the autox and track events I was doing a lot of at the time).

 

Interesting, I see that BMR also has upper and lower A-arms available. I assume I will need something adjustable so I can correct for a bent spindle. Are there any arms that are adjustable when installed on the car? I wonder how difficult getting these things set up will be? I'm thinking it would be nice to upgrade parts and not have to spend a lot of money purchasing stock parts instead (straight LS1 spindle.) However, I'm probably better off getting rid of all bent parts to fix the problem instead of fixing the symptoms. To many confusing options and no clear answers.. :[

JeffA

 

Yeah, I would try replacing the probably bent knuckle. The problem is that when you get used parts, you don't know what the car was like they came off of (unless you actually get to see the car firsthand).
Do you autox with the locals in LR? That's something I thought I might want to try sometime.

 

Yeah I think I better either find some straight used LS1 spindles, or get new LS1 spindles or do a different brake setup on my LT1 spindles. Shoebox I autocross with the ARSCCA http://www.arscca.org/ . You should definitely give it a try. We normally get a handful of f-bodies. Most of them are near stock. My car is normally the most heavily modified. As such I'm classed in street mod where I normally get my but handed to me. It's all fun though. You should definitely come try it out. Feel free to email me if you have any questions or need any extra encouragement to show up.

JeffA

 

Hey shoebox, I want to take this opportunity to thank you for your excellent web site and tech guides. Today I replaced my dying drivers side window motor via you guide. While it took longer than I anticipated it worked out great. I think I'm going to like not having to wait 10-15 minutes to get my window up.

JeffA