The Alstons mounting brackets already have the holes for bolts & the bolt to use arew optional. So even if you weld them in, the holes are still there.

 

I'm afraid to run the inner style SFC's because the last thing I want to do is minimize my ground clearance even more. I should get a ground clearance measurement to my floorboard and see how much (if any), I'll lose. BTW, BMR has their perimeter style SFC's listed as bolt-on on their website. I also believe that there are some Summit brand SFC's that are bolt-on but they don't tie into the from subframe at all.

I got that measurement with before and after measurements at the fender lip. And BTW, the before measurements were within .25" of three other stock height cars that I've personally measured as well. Did your parts car still have the bump stops? If so, that'll hold the car up about 1.5". And yes, I barely have any suspension travel at the moment until I modify a few things.

 

EDIT: Nevermind, found it.

I did have one other question though. For those running inner and outter sets what have you used? Id like to go all bolt on. I was originally going with S&W because my friend has them but the place he got them from wont have a set for a while i guess. Any suggestions would be great.

The comp engineering ones are outer, right? Would that be a good combo with the alston inners?

Thanks

 

Just got my Alston SFC's in the mail. Less than 20 lbs together which is nice. When i tilt them side to side i hear little noises though, almost as if there is sand or something inside, that normal? Any one else notice that? Its seems really minor though and they seem solid. Cant wait to get them on the car. Just having the body shop check the body and chassis and they're going on, cant wait. Thanks for all the info you all gave me on the subject, apreciate it.

 

its weld slag... its normal to hear some rolling around. On most closed peaces. .. unless thy blast before they coat and some sand got in a spot that wasn't fully welded

 

thank you guys for using this thread and keeping it alive, i am watching, but i dont want to give an opinion or answer questions because i dont feel im am experienced enough to do so, hopefully others will answer your questions, and it seems like they are, i started this thread because i had questions, and everyone has been a great help so far, thank you to all

 

Can you update your original post to reflect the actual measured UMI weights I posted? The 60lb estimate is a lot heavier then they really are. Some people may not read through the rest of the thread.

 

definately will i missed that myself, thanks maro
ok done

if anyone else finds something that i forgot to include in the first post, please let me know and i will edit it in, would be nice to have most of the pertinent information easily accessible in the first post, thank you all

 

looks like UMI and Alston, would be the lightest combo, untill we have confirmed weights for the others anyway

 

Alston is slightly lighter than MAC, but SPOHN i'm almost certain is lighter than UMI.. It's a thinner tubular bar. I unfortunately don't have SPOHN weight tho..

 

spohn says theirs weigh 44lbs... umi 36 :/

 

So ill be ordering some Alston and some Jegs SFC soon if all goes well. Is there anything i may need to worry about as far as installation?

 

Dang I feel like I got screwed out of 8 pounds of weight reduction lol

 

I double and triple checked the numbers for UMI when I weighed them.

Seemed light to me too but thats what the scales showed.

Maybe Spohn lists the shipping weight?

 

Spohn, UMI, MAC & Alston are the only SFC sets I have weights for on my Excel Weights chart.

 

Im not sure were the 44lb number came from for the sphon sfcs, but i just weight mine that i received in the mail today and they are 26lbs. Just an update for anyone reading.

-Zoe

 

26 each or 26 pair?

 

The pair, including the 2 pieces of tubbing that tie into the subframe

-Zoe

 

26 would make more sense, they are only 1 3/4 round tubing and some simple brackets. Not possible to weight 44lbs

however, didnt Spohn have boxes SFC's years ago? maybe they weighted 44 lbs?

 

Honestly I'm not sure if they did or not, it is very possible. but yea i saw that 44lb figure, and went and weighed mine instantly because i had remembered seeing the shipping weight on the box was 28lbs.

 

i edited the weight of the Spohns to reflect the 26lb finding, thank you, i did get that weight from Spohns website ...
if the alstons and the spohns can work together... 41lbs

 

I Edited my Excel chart of all the parts weights that I've collected over the years.

 

No problem man i just wanted people to get the correct info, as i did loads of research to find the lightest most effective sfc combo, the alston sphon route you mentioned is exactly what is in the plans for my car

-Zoe

 

nice i believe thats the pair im going with as well

 

Is there anywhere to buy Alstons besides Alstons website? They arent and havnt been in stock for a while now.

 

http://www.top-downsolutions.com/cha...8aka-f-body%29

 

Thank you. Now if only the site wasnt being updated. lol

 

Call Lon. It has been "being updated" for like a week now. Lon has posted here on TGO for the last week apologizing for the site being down & telling people to call.

 

It appears everyone is really obsessed with the weight/price ratio. and evaluating bang-for-buck that way. but really, if a set thats twice as heavy is 3 or 4 times as rigid, wouldn't that be a better set to have? it would be interesting to start a collective effort to gather some data/specs on the sets. I'm sure any of the reputable companies engineers have performed tests on their sets.

What about the various alloys the companies use for their beams? or welding/manufacturing processes? also, the debate of square vs round tubing is interesting as well. ultimately the tied subframe is trying to resist a torque in a plane, a geometry which can't really resist it well even if it were filled solid (hence rollbars). But if we consider the two designs (square/round) the square tubing is better are resisting a bending moment than the circular one, and the circular one is better at resisting a torque along its axis. It seems like a compromise really, maybe the perfect sfc's would have some square and some round tubing. I wish i could shed some more light on it, perhaps someone else can. in the mean time i'm going to do some research on it. Nodal patterns have very good torsional resistance, but are impractical for a subframe.

Anyways, I think a proper comparison here would ultimately be to rate it based on Torsional-rigidity-increase/(weight*price). that is, if we can round up the data.

 

Interesting idea of having some round and some square. I guess that might depend on where the stresses are..

 

I would LOVE some data like that, I think that it is important to leave price out of the initial equation being as that is subjective to the individual, weight plays a huge roll is how every car preforms, and being as these are not light cars, i feel that it is very important to cut weight were ever possible. but to never sacrifice performance to loose it, this type of data would be perfect for this type of comparison.

Personally I am attempting to piece my car together (not just sfc wise) using information from these forums as well as personal experience using the lightest yet still most structurally sound pieces available, and still taking into account how the pieces will work with one another to make the suspension function properly. Personally i went with sphons round tube design sfc, being as it was the lightest full length connector that welds along the pinch weld, being as the increases chassis rigidity as well. In the future i plan on adding a set of alstons to the inner rails, i feel that being as i am building a Road Course car the extra 19lbs low down is worth the subframes being properly tied together to increase rigidity in a high g cornering situation.

But, in my opinion S&Ws design is superior to EVERY other "single setup" out there. It is bolt in, so welding in after first bolting it in will be a breeze. It also connects the front and rear subframes together AND the outer pinch weld near the doors. It also proves a mounting point for there torque arm. But.. it has a lot of exhaust clearance issues with many peoples set-ups (including mine) unless you are at a point to redo the exhaust after install. But opinions aside, I would love to see some structural analysis data (not limited to sfc) so some of us can take the information and built our cars to their full potential using best components from each company.

-Zoe

 

round n square debate is sort of moot when a bender comes into play, why so many use square tube, its cheap and easy to run straight pieces.
AKA its a short cut for more profit, not for the best fit or performance.

SFC like Alstons, are not cheap and easy, many slight bends in different direction so they mold to the body like a pro built piece should be done.

 

Can you install outer and inner SFC's or do you have to choose one or the other?

 

You can install both.

 

I couldnt find the inner ones the link didnt work for me

 

I had that problem last month. Alstons are history, but Mac Performance still offers the inners: No, can't link after all, they've dramatically changed the website, and apparently, the offerings. I'll go try the link I had.

 

Link isn't working for me, it's in this thread: https://www.thirdgen.org/forums/susp...ow-alston.html Let us know if it works for you.

 

Kind of curious about installing both inner and outer SFC's....is there some kind of advantage to that? Does one not stiffen up the chassis enough, so the other is required?? For the extra weight you're adding there must be some benefit.

 

That link didn't work for me either

 

I think I've seen no more than 3 threads about having both, but now it seems there are no more inners on the market, we'll have to do our own. From what I've read, and my own past experience, I'm sold that both is best. In my case, I'm doing a Comp. Eng. full roll-cage in my t-top, so I figure CE's 3111 outers would give the easiest compatibility.

 

http://www.top-downsolutions.com/cha...rd-(aka-f-body)

Link^

 

Alston inner SFCs link over at TDS.....
http://www.top-downsolutions.com/cha...8aka-f-body%29

 

Nice! And thanks! But why the heck are these half again the cost of the MACs? I find that extremely angering, trying to take advantage like that. Still thinking fab my own. Wouldn't cost even a fourth as much.

 

you get them cheaper direct from alston, then a 2nd party who will remove the bolt kits that come with with from alston free and charge you extra for it.

https://www.thirdgen.org/forums/post...09-post20.html

 

Just checked my TDS receipt & compared it to the price in your link. Exact same price for my Alstons w/shipping as posted in your link.

 

yea they are the highest prices and charge extra for the bolts that come wit htem free from alston, I used dougherbert

 

You misunderstood. Your link was the SAME PRICE as what I paid for the Alstons from TDS so no....They aren't higher, yet you made it sound as if your link was cheaper. But it isn't.

 

And no, they do not charge extra. Same price if you use the bolts or cheaper if you don't My receipt has 2 separate lines. 1 for the SFCs & 1 for the bolts. Add them together & they equal the price on your link.

 

I personally would never waste my time with inners.

Here is my old car with just Spohn round tube outer perimeter style SFC's with them MOST IMPORTANTLY increment welded along the span to the rocker panels both inside and outside every 6" along the length (1"-1 1/4" welds).

The car would teeter totter on a curb it was so rigid. It would not do this prior to the sfc install- SPohns eliminated most of the chassis twist- inners will NOT do that. You want more? box the chassis with a cage.

 

You are really missing out, the inners truly connect the 2 subframes directly, the outers do not.