I recently had the opportunity to be the guinea pig for a new prototype weld-on set of sub-frame connectors for the B15 (00-06 Nissan Sentra). While I was a bit apprehensive initially (thoughts like “weld this at the wrong angle, and you could have problems opening/closing your doors” ran through my glass half-empty type of mind), I decided to give Sean and the guys at //TMS a shot. While you should read the rest of this post, I will let the cat out of the bag a bit – these things rock!
Driving Impressions
Three days later (drove up to St. Cloud on Sunday morning to have them welded on), I am even more impressed! To be honest, I have yet to find something to complain about. They make the car feel more solid, allowing my other suspension modifications to really do their job. Everything from low speed exits of my driveway (which I usually leave at an angle, and could feel the body flex as I hit the road) to high speed sweeping corners (the car’s other suspension modifications can really shine now, even on mid-corner bumps, which used to really unsettle the car) just leaves the car feeling like something other than a four door economy car. I have put about 600 miles on the car since leaving the shop, and my impression just keeps getting better! Even my wife (who was kind enough to tag along for the ~300 mile round trip) commented on how connected the ride felt now a few miles after the install, before I had even commented to her on how I felt about them.
My car
For reference, my other suspension modifications-
* Nismo FSB
* OEM endlinks with ES bushings
* Tanabe Sustec 4pt lower tie bar
* Tarmaq 4pt rear "tie" bar
* full nismo hard rubber bushings set
* Sachs Sport OEM-replacement shocks/struts
* B15Motorsports rear upper shock mounts (includes ES polyurethane bushings instead of squishy OEM rubber)
* bent rear beam
* pretty conservative alignment (winter will come sooner or later here, so within factory specs)
* 15x6.5" Konig Traffiks with pretty worn 205/50-15 Falken Azenis RT-615
Install
For those of you fearing availability of a 4 post lift (to keep the car's weight on the wheels when welding this on, which is essential), we worked around it in //TMS's shop by testing fitting and then tacking the connectors on while the car was on the ground, then raising it on a 2 post lift to do the final, complete welds. This method works just fine, but you might have to bribe somebody else a bit extra to want to crawl under the car on the ground to make the tack welds (it is a very weird angle) - or it might not be feasible if your car is lowered too far. By all means – if you have access to a 4 post lift, that makes life much easier, and probably will shorten the install time as well.
Sean (of //TMS) and I also had a pretty in-depth discussion about the possibility of bolt-in vs. welding for attaching these. He had originally planned to offer this with a rivet-nut option, but is backing away from that as it opens them up to additional liability (his thoughts anyway). In looking at the underside of the car, it is do-able...but would require removing lots of interior pieces to get to the true floor to do some drilling, and might ultimately be worse labor-wise than just finding a welder.
All of that being said, the installation of the sub-frame connectors is pretty straight-forward. At a high level, it would involve the following:
* Get under the car and line up the connectors. It should be pretty obvious which piece goes on which side of the car, as they tuck up nicely against the underside. The rear of the bar should bolt up to the rear trailing arm, and the front should sit just about even with the front of the front doors (if so equipped, your car has a triangle bracket on the underside of the car, just in front of where this piece goes).
* Mark the underside of the car with a line on either side of the three tabs with a sharpie. This will be the areas where you will remove the rubber undercoating to get down to bare metal in order to weld the sides of the tabs on.
* Remove the rubber around the marks made in the previous step. By trial and error, it seems that a grinder with a twister wire wheel attachment worked the best for taking the rubber off quickly and easily.
* Get the car to the position to begin welding. If using a 4 post lift, the car can be in the air. If not, have the car on the ground with the weight on the wheels.
* Remove the nut for the bolt going through the rear trailing arms, and put the rear end of the connector over the bolt (don’t tighten the nut at this point). Line up the bar as it will be attached and support it somehow (in our case, the initial welds were done on the ground, so a couple of floor jacks did well to hold the bar in place). Grab a spray bottle of water, as rubber near your welds has a tendency to want to burn!
* Make your initial tack welds to hold the mounting tabs to the car. Once you are satisfied with this, full seams along the two outer edges of the tabs can be completed.
* Once the welds are satisfactory, finish them with some form of covering (primer, paint, undercoating, etc.).
* Repeat for the other side of the car.
* Once all of that is complete, torque the nut on the rear trailing arms to factory specifications.
* Get the car on the road, and test drive. Keep in mind that you have changed the handling dynamics of the car, so it is strongly recommended that you do not push the car too hard until you are sure that the install was successful, and that you have become re-acquainted with the handling characteristics of your car.
Implications
For the auto-xers in the group, this does pretty much guarantee a bump to the SP arena (
http://sccaforums.com/forums/thread/269011.aspx)...but if you already there, or drive you car 6 days a week and race it on the weekends for fun, this is definitely a worthwhile upgrade! The guys at //TMS seem genuinely interested in providing a quality part at an affordable price, and are doing everything that they can to get this right (last they heard, Nissan Sport magazine still had their prototype set wrapped in packing material, which is why there were so anxious to find other testers on here). I don’t know what this would do to your factory warranty, so if that is still a concern for you…keep that in mind I guess.
For everyone, you should be happy to know that ground clearance is not affected at all! Sean did a great job of designing these so that they tuck up against the car’s underside perfectly. The outer edges sit pretty much flush with the inside of the pinch weld (hidden by the OEM sideskirts, if your car is so equipped), but is positioned in such a way that both factory jack points (the spots along the pinch weld with two grooves closely spaced together) are still accessible. The rear of the connectors bolts in to the mounting point for the rear trailing arms, so again the rear trailing arms of the beam axle are actually closer to the ground than the bar itself. When standing five feet from my car and looking at it, you can see only a small portion of the bar under the car, but other factory pieces on the underside of the car definitely still hang lower.
As you can see in the pictures of the prototype, there are a few only open ends on the connectors themselves. I have spoken with Dan of //TMS to ask if this was a concern, and he did mention that they will be providing plugs with the production piece, so you won’t have to worry about water or other debris getting inside of the bars and causing issues. For those of you looking for that extra piece of mind (and who live in the rust belt like me), you can also purchase a spray can of rubberized undercoating at your local hardware or auto parts store and recoat the area around the mounting tabs of the connectors.
Full Disclosure
I did receive the parts and installation for free in exchange for providing a full review thread on here, along with assisting in authoring the install sheet that will be sent out with any production pieces. That being said, I would gladly go back and pay for these, and would recommend both the parts and the guys at Truax Motorsports with confidence to anyone looking to improve the handling, feel, comfort, and everyday drive-ability of their Sentra.
Truax Motorsports
Taken straight from their website – Truax Motorsports makes chassis bracing for the Nissan Maxima, now the Nissan Sentra, and other cars. The team has over 30 years experience welding, fabricating and running small businesses. Mike, Sean, and Dan are proud to be a part of the Nissan community, and strive to make your experience with them positive in every way.
Their marketing line aside, it really was a very positive experience working with Sean and Dan. Sean is a very knowledgeable car guy, and truly very gifted under a car. If you happen to be in the area, I would definitely recommend stopping by and having them install the connectors for you – you get a quality product, a good installation, and get to talk cars the entire time!
Feel free to ask any questions, and if you are ever in MN, you are more than welcome to get a first-hand opinion for yourself!
