I want to install some subframe connectors, I'm sure weld in connectors are better, but are bolt ons ok?

 

My SLP bolt on subframe connectors work great, and they have the advantage of being removable. When I sold my '94 Z-28 and got a 2001 SS, I just unbolted the subframe connetors from the '94 and bolted them onto the 2001. Easy.

 

Excellent, good to know thanks

 

bolt in sfc's are pointless. lol unless you have some absolutely massive bolts and torque them to 200 ft.lbs, you might as well forget it. bolt ons allow flex through the bolts. sure, it's going to be better than none at all, but it's a waste of money. buy weld ins and you'll be set for a ton of power. bolt ins wont take a ton of power, however they are fine for 14 sec cars. UMIperformance.com has weld ib, boxed sfc's for 139.99. these are quality pieces. the owner garantee that they are as good or better than bmr or spohn. i bought these. nice powdercoat and very strong. can't beat the price

 

Had bolt in BMR SFCs in my 94 and never had a problem.

 

Thanks all...are SLP's worth the extra $?

 

I just got a set of edelbrocks. A bit more $$$ than some, but massive brackets, and really nicely made. I can let you know about install ease by monday.
Really, welded in is the only way to go. The edelbrocks might be great for you, because you install one bolt on each end to fit it tight for welding. So you could do most of the install at home and bolt em in, then drive it to a welder for an hour's work. They're one of the few designs that fully piggybacks the trailing arm mounts. Good luck with it

 

SLPs are the best design, hands down. They are even better than the only other diamond design, the KB. They use better material, and bigger material where it needs to be strong. Seen some pics of the KBs after hard use, and they werent pretty. I have the bolt in SLPs. While it is true that they do flex slightly more than the weld in SLPs, they are still better than all the non-diamond design weld ins as far as performance goes. My bolt ins work great, dont come loose, and I did build my own hardware with bigger bolts. As for price, there is a guy on ebay who sells them. They arent listed as SLPs, but trust me, they are built by SLP< same exact product, at much less cost. I believe he sells the weld in ones for like 150$ (same as the bolt ins, just arent powdercoated and dont come with hardware), and the bolt in ones for like 190-200$.

 

umi is pretty damn good stuff for cheap.....

 

What wasnt pretty about t he KB subframes once they had some use??

I am in the market for subframes so I would love to know...
thanks.

 

The whole point in adding SFC's is to increase the stiffness of the chassis. Otherwise, they're just extra dead weight, like carrying a few barbell plates around with you all the time.

Any place in your installation where relative movement can occur between the existing chassis and the SFC represents a place where you're throwing away some of that stiffness improvement. Bolt holes have clearance so that you can install the bolts, so if you aren't developing enough friction by reason of bolt torque to hold things in place, slippage will occur. And that's seen as lost stiffness. Not all of it, probably, but why give away any? And guess what - bolts sometimes do loosen up.

While I haven't run any numbers, I don't think it takes much slip or other relative movement to give up a significant amount of the total stiffness that you'd develop with properly weld-installed SFC's.

Norm

 

The main beef I have with SLP weld ins is that they aren't powdercoated. You could go have them powdercoated, but then they will end up costing more. Or you could spray paint them, but I would still be worried about rust.

 

I have the UMI Performance 2 point weld in and I am very happy with them. I didnt like the SLP because of the size and ground clerance lose.

 

The triangulated (SLP) design is unquestionably better than the traditional design for strength, as it ties to the center of the car. But I'd think you'd need to upgrade the trans X member, or add a driveshaft loop to better tie the sides of the floor together. Personally, I was concerned the extra bars would interfere with my non-SLP exhaust.
S&W racecars has a really nice looking set with a full crossmember that is advertised to work in harmony with stock stuff, or can be used to mount their tubular torque arm.
If you've ever seen the hi speed films of a rocker arm flexing, you realize that metal is actually a very dynamic, moving thing in use. It only looks stationary, lots of little wiggles going on through your frame when you hit bumps and do WOT shifts. That's why you have to weld them. Even tightly bolted joints will move in small amounts that you can't see. Might even squeak. Good luck!

 

what ground clearance loss? they become the lowest point after installation by like 1/8", but if you would rather your tranny hit then thats cool too I guess.


You have to paint the weld on because you would have to grind off where you weld anyways, and thats where I would be most worried about rust regardless, unless you paint them while dirty or park your car where high tide reaches the bottom of your car.

Use some of the rustolium hammer paint, its thick and tough so rocks wont chip it, but even with just normal paint a couple of costs on a clean surface wont rust, the bottom of your car isnt powder coated, but yet it doesnt rust.

you also pay a good amount less for the weld in cause of the no powdercoat.