Who makes the best 2" drop seat kit?

[ViperTony]

Thanks Mac. I've come to the conclusion that a true 2" fixed seat drop is not possible in GenI/II Vipers unless modifications are made to the tunnel and floor pan/firewall area. At best, all I could manage was a 1-1/4" drop for the rear of the seat and at that point the seat frame rests on a few protrusions noted below:

Maybe an 1 1/4" drop tops back there. (Sorry for the grass and dirt in the carpet...that occurred when I went off-track at Limerock back in '06. Time for some detailin'. ) However, the front of the seat can be dropped two inches. If I implement a 2" front drop and 1 1/14" rear drop...the seat feels as if it's level and I lose the 1 1/4" Front-Back decline with the OEM setup. I'm going to stick with making an adjustable version since that gives me the maximum 1 - 1 1/4" drop in the rear anyway. However, I'm going to make two different sized front mounting studs: 1" and 2" which can be switched out by the user. They simply bolt into place.

Quite frankly, the first couple of fixed brackets I made don't work for me. I really don't understand how the stubby 2" kits hold up over time. Mine sagged, bent since there's nothing to support them as they hang over the floor pan area. I tried 1/8", 3/16" and 1/4" thick steel flat bar and each gave to some degree and bent. Except for the 1/4" stock. However, I felt that there would be too much force being placed on the front/rear mounting studs/bolts with that design. I sometimes see used 2" kits for sale and almost every one of them are bent in some manner.

I apologize this is taking me so long...I keep meandering off track. After getting a welder (yes a Craftman MIG from an incredible sale at my local Sears store), I had to run a dedicated 20amp circuit (prepped for 30amp and TIG down the road) for it. I couldn't weld without some kind of welding table so I built one 48"Wx32"Dx36"H out of 1.5" square tube stock and plate steel from the local bargain tent at Logan Steel. Ugly as sin but I love it. Will clean it up and powder coat it when I'm ready to paint the tracks:

This is what the GenII brackets look like. They measure 20" end to end. The GenI/I.5 brackets are shorter in length and don't have the hole on the side. I'll post pics of that later:

Despite how much I love McMaster-Carr they didn't have the mounting studs/posts I was looking for. So I decided to get some 3/4" diameter steel rod stock and cut, drill, tap and thread my own:

I found dual-locking seat sliders that are well made and with some slight modification that line up well with the mounting tabs under the seat frame. Additionally, the mounting points can be moved around slightly by loosening the bolts just in case there are slight variances with the stock seat frames. The rear studs will be welded on to the slider whereas the front studs will be bolted on from the bottom. This will allow one to choose between a 1" or 2" drop for the front of the seat:

Someday I will need to dust-off CAD and get my drawings into the computer. In the meantime, I found some cardboard that does the trick. For those of you wondering, YES, for a day or two I contemplated taking a plasma torch to my wife's All-Clad pots since the handles would've worked well in this application. After a few choices words from the wife, I let that idea slide:

I will post more pics later regarding removing the seat, seat bottom and the acts of God needed in order to mount the fixed 2" kit. But for those of you wondering who makes the seat cushion materal, it appears to be Dynaflex. I'm contemplating shaving off a 1/2" or 1" layer of rear seat cushion material to get that extra drop:

I've been experimenting with what to use for the actual support piece the slider attaches to. It has to span 20", be lightweight and sturdy enough not to bend under my weight or at least not bounce around. I've found some 1.5" wide structural aluminum U-channel from my steel place in addition to steel u-channel. Both will do the trick but whichever one I get the best discount on wins.

For those of you wondering where I'm going with this project. I'm not sure. Worst case I will put together a detailed write up with parts list. Best case, if there's any interest, I'll send one these off to a good friend here and see if we can produce and sell these at a reasonable price. I'll post more pics, progress in the next day or two.

 

[Big Mac]

I understand completely. Still healing a bit from surgery so whenever you get done is cool with me.

 

[V10SpeedLuvr]

I understand completely. Still healing a bit from surgery so whenever you get done is cool with me.

Everytime I see you post, I'm gonna think its me now I read your post and was like "when the hell did I have surgery...Oh wait, thats not me"

Good luck with your recovery!

 

[Big Mac]

Any updates?

 

[ViperTony]

Any updates?

Sorry I took so long to respond. PM sent.

 

[ViperTony]

Here's an update of where I'm at with the seat lowering project. I decided to turn this into a detailed how to since all of the materials I'm using are available off-the-shelf and, quite frankly, there's nothing proprietary about them. A formal writeup for GenI/II with drawings, measurements, part lists, etc. is on the way.

I made two versions: a fixed 2" kit and a movable 2" kit. For the fixed version, after a lot of measuring, fitting, cutting, measuring, etc. its just a matter of obtaining flat bar steel stock from Lowe's/Home Depot or one of the many online steel supply sites.

I made several mock-ups that entailed welding, bolting, etc. Additionally, I was looking for specific standoffs that I couldn't find and ended up threading my own but I found some readily available 3/8" couplers that does the trick. In the end you don't have to have a welder to make these kits.

Here's a fixed 2" front seat bracket that uses 3/16" flat bar steel and 1-3/4" coupling but fastened by a Grade 8 bolt to give a 2" drop in the front:

I used 1.5" wide steel because that's what I had in the garage however 1" wide is sufficient and gives some wiggle room when lining up the brackets to the seat during installation. The 1/8" flat bar steel or aluminum is too flimsy and will not hold up and bend under the driver's weight. (well, at least my weight). 3/16" seems to do the trick.

Bottom View:

For the rear, same idea except I cut down the nut to achieve a max of 1.5" drop in the rear. This places the bottom of seat as far back as it will go against the firewall. If legroom is not a concern, the bracket can be made longer (about 1" more), the nut removed and the bracket bolted directly up against the seat frame to achieve a true 2" drop in the rear. This is didn't work for me since my knee ended up in the dashboard.

After test fitting the fixed kit to the seat and installing (which was awful) I noticed a huge difference. Seat felt much lower, wearing my helmet it no longer rubs under the hard top which should make track days more fun. It does feel odd to be that low but I got used to it very quickly.

I had my wife sit in try it out..she's .not a fan of the lowered seat. She's shorter than I am and reaching the pedals now was impossible. Considering that we team up on events and she enjoys driving the viper too, I needed a compromise. I was not going to swap out seat brackets every time one of us wanted to take the Viper for a drive.

So, after some measuring I realized I can make a movable 2" version as well. Low and behold I found a dual-locking, sliding mechanism on SummitRacing. Summit SUM-G1153 - Summit® Universal Sliding Seat Brackets. This is a common bracket kit for aftermarket racing seats. Very well made and very sturdy. Not bad for $20. Yes...$20.

However, this sliding mechanism needs a little modification to work:


A pair of steel tabs 1-1/2" wide are needed on either end of the sliding mechanism in order to bolt it up to the seat frame. Some 3/16" steel stock was used for this. Additionally. these need to be mounted to the slider. No problem, slider came with pre-drilled holes. How convenient is that? You can either bolt on or weld some stand-offs (as I did earlier) on to these tabs. They will be used to connect the seat from to the slider.

Using the same coupling nut, I cut them down to achieve the same 2" front drop and 1.5" rear drop as the fixed kit. In this version, I used some washers and a locking nut (not pictured) underneath the rear bracket to get it to mount to the seat securely. Just another option if you don't like or know how to weld:

The other nifty feature of this sliding bracket from Summit is that it has two bolts mounted underneath to fit it against a floor board. These bolts can be used to mount the slider to a bracket spanning 20" between the front and rear mounting locations on either side of the floor pan. It's a great alternative if you don't want to weld them. I also learned another trick that these bolts are good for, more on that later. The slider is not strong enough, nor long enough, to be used on its own without a supporting bracket. The sliders are also NHRA compliant, according to Summit.

Pic of the bolts:

The pic above shows the slider mounted to a 20" long piece of 3/16" flat bar steel. I would've preferred 6061 u-channel aluminum measuring 1.5" wide with .5" legs but I cannot find it. The aluminum would be much lighter than the steel flat bar or even u-channel steel. However, the 3/16" seems strong enough to span between the mounting locations without bending or bouncing around while driving (even under my weight).

About the bolts protruding through the bracket. Those can be trimmed but I've found that they can be used as 'feet' since they barely touch the rug when installed. In fact, the slider kit comes with rubber feet for these. I now understand how some other after market lowering kits get away with flimsy 1/8" brackets...its the feet.

The downside to this movable version is weight. They are noticeably heavier than the OEM seat brackets. I haven't weighed them yet but I'm betting they're a pound heavier. If anyone knows where I can find 1.5"W x 1/8" or 3/16" thick X .5" legs aluminum u-channel (not mill grade, 6061 would be ideal). Let me know. This would significantly reduce the weight. However, the advantage to this movable version is the use of installation...and the fact it can be moved. Not sure I want the added weight. I guess I can lose a few pound to compensate.

These are one of many Frankenstein brackets I've been experimenting with. It's easy to look at them and say it's not complicated. I beg to differ. The most time-consuming part of this endeavor was the measuring, test-fitting, installing/removing the seat until I got it just right. Cutting, drilling, assembling was very easy. Hopefully some of you are interested in this and will the find the upcoming writeup helpful.

- TP