Okay so the point of subframe connectors is to of coarse tie in the subframes and "tighten the chassis" and for it not to flex. In essence a cage allows the chassis not to flex as well as a safety net around the driver. I am currently building a nitrous car that light is the keyword so a cage is going to be needed and with a cage install I am thinking the subframe connectors would not be needed and I'd be able to save that weight that comes with installing them. Am I wrong? Are the subframes still needed?

 

Ive searched this myself a couple times. I decided i was giing to do both but to test just the cage first. My car will be on spray also in due time. But I ran a couple motor passes with just the cage. 1.4x 60' times foot braking from around 1500 and the car stayed extremely strait in my opinion. Im also on stock springs and shocks, stock rear sway bar, tunnel mount torque arm, addjustable lca's and pan hard bar. Simple and works. But for the minimal weight of sfc's definitely worth it in my opinion.

 

Well I'm looking for a 3k race weight with looking stock body and interior has to be intact so every lb counts and glass has to stay stock so I need every break I can get.

 

My car w/o me and under 1/8th tank of gas was 3550. I honestly dont see how you guys get down so far in weight. I think I could get car to maybe 3350 but thas probly as far as I'd feel cutting stuff out for the street.

 

For the strength/stiffness aspect do both. As for safety, I think the subframe would be a little bit safer.

 

If you are planning a cage for sub 10 sec or a 6-7 point roll bar for 10+ runs step up for Chromoly .083" wall 1-5/8"and 1-3/4" tubing, it's about 34% lighter than mild steel (.134"wall), every 100lbs of mild is about 66lbs. of 4130 in the same dimensions, adds resale value to the car too.

 

I don't have a cage in mine. just sfc. A cage is in the car's future i can say that. I was reading some where on here last week were people were talking about some of these companies SFC's are a waist of money. Its was said that the only one's worth buying are the MWC SFC's I don't know why that is I haven't finished my home work on it. If I were in your position I would do both and figure out which ones are worth doing.

 

The cage will be a true 8 point chromoly with halo that MWC chassis sells. So it be stiff to say the least. I am going to give them a call tomorrow and see what they say

 

That's the cage I got. Driver side swing out is really nice. Got it NHRA certified to 8.50. Inspector commented on how nice the cage fit.

Cage really tightens the car up. I still have 3pt UMI sfc's bolted in. I bought a straight set from MWC I need to weld in. I don't know if they are actually necessary but for 15lbs id say it's not a bad thing to have them, especially if your car is 60ft'n like crazy.

 

Just wanted to chime in and clarify a few things here;
Yes, it is a very good idea to have SFC's with a roll cage. They tie in at different points in the chassis and do slightly different jobs. Unless you are doing a 25.x chassis, then I would absolutely do SFC's. Even then I would still put in something to directly tie the rear and front structural areas together.

As far as the old "true subframe" versus tradition SFC debate... that can go on for days. Connecting the true rear subframe to the front of the car does add structural rigidity, but it does not connect where the force is being applied to the chassis. If you want a good combination of both strength and light weight that will do the job you need, you can go with our tubular SFC's. They tuck up tighter in the chassis than the standard boxed sfc's as well

http://bmrsuspension.com/index.cfm?p...&productid=313

 

IF it was me, I would put the floor structure in for a 25.3 and mount your 8.50 cage all to that, so that the structure for a 6.50 is there under the car, run the cage thru the floors to it, take the back and run the back portion you need for the 25.3 as that's where most of your flex is and just don't do all the underneath bars, and the drivers halo. Put the X in the doors for safety, and the dash bar, just leave the stuff you don't need out.

Car will be plenty stiff this way and if you need to ever upgrade it you can, and didn't put any weight into it that you don't have to have. And that extra that's in the back will make the car "work" a lot better and lock the back of the car up before it ever gets sacked out from racing it a lot.

 

Give us a call whenever you have any questions or you can email me at midwestchassis2@hotmail.com

 

Glad to hear an inspector made a good fitment comment, it means we are doing our job well and you installed it well. We put a ton of thought and time into our cage kits.

It helps that we do installs with all of our products here on a daily basis.

 

Note the real subframe is nowhere near the LCA mount, let alone the outer portion of it. There are plenty of cars running extrememly fast with absolutely no reinforcement of the LCA mount. The 82-02 F-Body car does not need help in that area like the Mustangs do.