# Drag racing mod for rear suspension of chevy cruze



## TravsCruze (Aug 4, 2011)

okay, for those that have been following one or both of these threads, this suspension mod and my trifecta tune are my next steps towards a little lower ET's. And since it is a suspension mod I decided it probably should go here and i'll reference back to it on these other two threads. This is a DRAG STRIP ONLY MOD, it IS NOT for the street PERIOD. It would be a huge safety hazard to drive like this for any distance. 

http://www.cruzetalk.com/forum/34-1-4l-turbo/2323-has-anyone-done-quarter-mile-their-cruze.html

or my thread

http://www.cruzetalk.com/forum/9-chevrolet-cruze-general-discussion-forum/3118-eco-cruze-dragstrip.html

This cost about $10 in materials, and took just a couple mins to do once I got the freaking car jacked up. BTW, without the OEM jack, Eco's are one of the most floor jack unfriendly vehicles i've ever owned. It took alot of moving it around to get the jack stands in a decent spot to do the drilling.

There is a small pilot hole in the base of each spring perch, so it was easy to drill out using progressively larger drill bits till I got to a 5/8" bit. 

Then I built the cup that would sit on the top of the 5/8" all-thread bolt

When its time to install at the drag strip I will have to jack up the rear just a little to get the top cup in, then feeding the all-thread through it with the nut and washer on the bottom till its snug on both sides with a third nut and washer on the bottom of the perch to make sure everything stays in place like its suppose to. Then using my shoulder I pushed up on the trunk floor and spun the bottom nut down some more. Car settles down onto the all-thread and can't squat to transfer its weight on launch or during shifts.






















































sanding off some burrs.. would hate to get one in a finger while installing and removing









this is everything (minus 2 washers) plus some scrap tubing I had laying around that I chopped up for some cups



















the welder and I had a disagreement about wire speed and welding nuts onto washers and I lost.. the results.. horrible looking welds but they will work for this limited track duty project.









after they are cleaned up and painted









feeding the all-thread through with the nut on the bottom









the top cup is on and I fed about an inch through to the other side so as to make it go up in the body. I don't want this booger coming out by accident









There it is all in place, I have a matching one for the other side so the rear can't squat, unless it bends 2 shafts of 5/8" steel. And if it does that I have worse problems than a couple bent pieces of bar. Also there is another washer and nut on the bottom of the spring perch I didn't take pics of so everything is locked in place.


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## FieroItaliano85 (Aug 5, 2011)

Video of this going down the track for first time!!!!


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## Aeroscout977 (Nov 25, 2010)

The last couple of pictures are broken links. Interesting thread hope to see the other pics.


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## TravsCruze (Aug 4, 2011)

JDM-USDM Love said:


> The last couple of pictures are broken links. Interesting thread hope to see the other pics.


hmm.. weird. It shows fine on my computer, all the links seem to be working from photobuckets side and loading properly.


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## thevoid (Aug 1, 2011)

This reminds me of the "cable mod" that some people do on the W-Body at the dragstrip, except this is probably safer...

Ontario Quebec Club Grand Prix • View topic - Cable mod = rad

ClubGP Message Forum troubleshooting


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## CHEVYCRUZE RS (Mar 29, 2011)

pretty neat


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## TravsCruze (Aug 4, 2011)

The biggest thing i'm hoping to get out of this is weight transfer being minimized then I won't have as much wheel hop on launch, if so then i can turn off the T/C for a little more power. 

its been pouring here all evening, so i'm seriously crossing my fingers it will dry up so i can run this tomorrow.


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## Aeroscout977 (Nov 25, 2010)

They work fine now. Google Chrome must have been acting up on my end.


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## shawn672 (Oct 31, 2010)

Something about this just screams bad idea... but good luck! I've never seen this before


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## NBrehm (Jun 27, 2011)

shawn672 said:


> Something about this just screams bad idea... but good luck! I've never seen this before


I'm kinda with you. When you use a cable you have flex in either direction. What happens when the body hits the top cup and there is a big old screw sitting underneath it that is bolted to the lower axle? I just feel like you are setting up for something to break here. It's going to reduce travel but I also think it is going to put a BIG hole/dent in something


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## Aeroscout977 (Nov 25, 2010)

It's basically a raised bump stop. Some people just put in "coil pucks" to cancel out coils thus increasing the spring rate. A set of tuned springs and a dialed in suspension is always better. I don't think he will be launching hard enough to cause to much damage. But springs and tires would have been sufficient considering it's a stock 16-17 second car.


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## NBrehm (Jun 27, 2011)

Bump stops are on a reinforced area on the car. I just don't like that big metal bar in there. I agree with you that I don't see a whole lot of weight transfer coming from this car but I'd put money on the denting the **** out of the upper spring seat. Not something I would do personally but curious to see if it works.


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## Memphis (Jun 4, 2011)

He just didnt want to wait for springs as he is going to the strip tonight. I might actually head down there and see how he does. It will be interesting for sure.


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## Memphis (Jun 4, 2011)

Lol. He also has a **** ton of time on his hands too. he does crazy stuff like this all the time supposedly. He is leaving for the track around 4-4:30.


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## NBrehm (Jun 27, 2011)

The only other concern I'd have is if the track has any bumps at all that rear end is gonna bounce around like crazy so be careful, hopefully it is a nice track.


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## Aeroscout977 (Nov 25, 2010)

NBrehm said:


> The only other concern I'd have is if the track has any bumps at all that rear end is gonna bounce around like crazy so be careful, hopefully it is a nice track.


Yeah shut downs can be rough at a lot of tracks.


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## TravsCruze (Aug 4, 2011)

The cup sits around the upper perch and there is already a hole where the bolt goes through. The ass would have to completely unseat itself to get that kind of movement. It would have to jump 2.5 inches into the air off the springs to come unseated. If someone wanted to cable it down after jacking it up they could easily do that if their car was going to be at the track all the time.

and yes its a very smooth track even in the shut down area. If it wants to hop around i'll just cable it down 

on the denting issue, there is a rubber block that the cup sits on, so no denting unless the springs are going to dent the metal as well.. haha.


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## NBrehm (Jun 27, 2011)

Sounds good, let us know how it works.

Cableing the rear would not help what I am talking about, with those bars in there you have basically eliminated spring compression completely (if I am looking at the picture right, you have the bar so it is touching the body when weight is on the car), so bumps can't be absorbed ont he compression stroke of the shock. That energy is going to go somewhere and without the spring it will lift whole car up as you will only have rebound. even with a cable to reduce rebound that energy will only go one direction, the path of least resistance, which in this case is going to be up. At the speeds you will be at it shouldn't be an issue but be careful, especially when you hit the brakes.


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## TravsCruze (Aug 4, 2011)

i'll post up the videos and time slips as soon as i get home. Its like a 80 mile drive.. yuck.


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## TravsCruze (Aug 4, 2011)

mod worked great!! Check out this nights passes over on page 5 of

http://www.cruzetalk.com/forum/9-chevrolet-cruze-general-discussion-forum/3118-eco-cruze-dragstrip-5.html#post39761


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## oshia86 (May 29, 2011)

Why not just get drag bags?


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## NBrehm (Jun 27, 2011)

I think it was strictly cost


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## TravsCruze (Aug 4, 2011)

nick nailed this one on the nose.. haha. Cost!! This was like $8 or something and worked pretty well. Even after I bought the cable and crap to tie everything solid after i have the links in place, i don't think i'm over about $30 for everything. 

Eliminating weight transfer and keeping the front planted is the issue, so drag bags or links, the outcome is still the same. 

Travis


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