how many pieces are there total from GT Spec for stiffening the subframe? I was browsing on their site, and saw two sets for the front, one is a 1-bar set up to strengthening the subframe, another one is a 2-bar set up which connect the subframe to the chassis, what are the different between those and from I can only do them piece by piece, what should be the order? Or which will provide the most improvement?

 

This is c/o Mark at GT Spec:

1. Rear M Shape Brace + Rear 2 Point Tie Brace
This will be the first 2 brace to get. These two braces tie the lateral arm and control arm together. These two braces act almost like a sway bar. We have tested the same braces on 350Z and the most effective brace so far.

2. Rear 6 point subframe brace
Because it's a bit pricey, that's why I list this brace as #2. If budget allow, this brace is a great addition. The brace link the rear subframe to the chassis. It added three extra reinforcement points per side. It's a 5 piece kit thus a higher price than rest of the braces.

3. Fender Brace
Fender brace ties the front engine compartment to your mid chassis. Known to be used on many track car, it provided extra reinforcement for the front of your car.

4. Front subframe tie brace 2/4 point.
I list this lower than the rest mainly because the front subframe are already very stiff. These two braces reinforce the existing mounting points. It still provide added reinforcement but not as much advantage compare to the rest of the braces.

5. Front subframe left + right tie brace
This brace is the last on the list because it's a significantly smaller brace compare to the rest. However, it does added two extra reinforcement points to the front subframe, but compare to the rest of the braces that's available, this brace has less effect.

 

The best thing to do is call GTSpec and have a conversation with them about your needs - just like I did. They will then proceed to tell you what pieces you should or should not get.

I need subframe as I have a long drive way with a bump that twists my chassis every day, I do canyon roads, and don't track.

So for me...they did the 6 point rear, strut bar, front 4 point ladder, front tie brace (left and right), and then the M brace (Rear Low Lat). I was not interested in the fender braces - but will be doing the Rear lower tie and the front lower tie just for measure when i start working again.

Yes it does affect clearance - but minimally.