[Cloud9...68]

It's getting close - one of the last things to do on my project is to install my Sparco Evo drivers seat. After kicking around the options in my head, I've decided I don't want to use sliders,and bolt the seat in directly, but here's the challenge: The distance between the floor rails the stock seat bolts to is about 16.5" (not at home at the moment to get an exact measurment), while the distance between the mounting holes in the seat side mounts is 14.5". So, I'm envisioning welding a pair of rectangular steel tubes to the floor going north/south such that the centers of the tubes are exactly 14.5" apart, drilling the required holes into the top of the tubes, and bolting the seat side mounts directly to them. But of course, the floor isn't flat - there's a nice flat area just inside the rails that contain the captive nuts that the stock seat bolts to, but these rails are elevated about 1/4" relative to the flat areas between them. Putting the rectangular tubes just inside the stock rails on the flat areas on the floor would leave them slightly too close together.



The only way around it that I can see is to "flatten" the floor by welding some plates that are equal in height to the rise of the stock rails, grinding everything perfectly flat, and then welding the rectangular steel tubes onto the flattened floor. While this seems to make sense, I'm wondering if there's a better, simpler way to accomplish the task. Does anybody who has done this have any recommendations? I'll post pictures to clarify what I'm talking about, in case it isn't clear enough from my description. Thanks.



Edit: Here are the measurements of what I'm talking about:



Distance between outer edges of bottoms of seat mounts = 17-1/8"

Distance between inner edges of bottoms of seat mounts = 13"

Width of bottoms of seat mounts = 2-1/8"

Distance between outer edges of stock rails on drivers side floor = 17-1/2"

Distance between inner edges of stock rails = 12-3/4"

Width of stock rails ~ 1-1/2"



So, the bottoms of the seat mounts cover most of the stock rails when I place the seat on the floor, which is why I think I need to elevate the seat on some hollow (rectangular) tubing to allow room for the heads of the bolts used to bolt the tubing to the floor, and the nuts for the bolts needed to bolt the seat in place from above.

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[flash]

i machined blocks out of aluminum that had both patterns in them.

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[Cloud9...68]

Do you have the same issue with your seats, in that the distance between the mounts' bolt holes is different than those of the stock seats? The part that I'm puzzling over is how to mount/weld the adapter piece (whether it's a solid block, or a square tube) to the floor, given that for the adapter pieces to be the correct distance apart, they land on a part of the floor that isn't flat.

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[flash]

yes, i had the same issue.



i didn't weld, and there is no reason to weld. i bolted the blocks to the seats, and then ran bolts through to the rails. you could do the same thing without rails, and just bolt the blocks to the floor.

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[94'968]

what ever you do don't buy the sparco seat bracket for the 944/968. it does not work on the 968. for my driver side i modified the sparco mount to fit because i bought it used and couldn't return it. on the passenger side i took the factory sliders off the old seat and welded in new steel pieces in between the sliders to make the width right. so the way it worked was factory slider bolted to the factory spots, then the racing seat bolted to the steel pieces which hold the sliders together.

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[Cloud9...68]

Joel,



I got an extra seat bracket (not sure if it's a Sparco) with the passenger seat I bought used, and you're right, it doesn't work, which is why I want to bolt the seat directly to the car via some type of adapter.



Flash,



Here's what my seat mounts look like (wish I knew how to copy a picture directly into a post):



http://pitstopusa.co...CFYGqPAodYT0AIQ



http://compare.ebay....mTypes&var=sbar



So, I have to bolt the seat via the side mounts vertically. But the problem is that the area of the floor directly above where the seat mount's holes are isn't flat. If the bolt holes were on the side of the mount, I understand how I could do exactly what you did, and bolt a block of aluminum vertically to the existing runner's captive nuts in the floor, and then bolt the seat mounts to the sides of the block. But with my mount holes in the vertical position, I don't see how I could do that. But of course, I'm sure I'm missing something obvious, and I feel a dope slap coming on...



Edit: Dope slap executed. All I have to do is bolt some aluminum blocks to the existing captive nuts in the runners as Flash describes, then attach the seat mounts to the sides of the blocks using some sturdy angle iron. Duh...

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[flash]

lol - i knew you'd get there

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[Cloud9...68]

Yeah, I'm starting to get a good mental picture of how it's going to look. Fun stuff.

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[Dubai944]

Same solution as others. I use a long steel plate on each side which bolts to the standard mount points then the race seat mounts are bolted to the plates separately.

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[craigawoodman]

Whatever you do, it needs to sit low. I am only 5' 10" and with a helmet on, there is not a lot of headroom.



Thought about sourcing a set of Club Sport seat mounts? Would these work (I am assuming the seats mount more or less the same).

Sorry, should also have said, mine are welded plates, not OEM mounts. Same as others, plates to the slider.

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[Cloud9...68]

Spent some time looking at it last night. The problem is that the bottoms of the seat side mounts are quite wide, wide enough to cover most of the rail area. However, the bolt holes sit too far inboard to be able to use the stock captive nuts. So I don't see how a simple steel plate (or aluminum block, or anything else that's solid) will work, because the seat mount will knock into the bolts used to bolt the plate to the nuts in the floor. I think I'm going to have to go back to my original idea of bolting a rectangular steel tube to the stock mounting points, and then bolting the seat mounts to the top of the tube. The tube should be about 2" wide by maybe 1-1/2" tall. Cutting and drilling a piece of steel like this is going to be fun... Do you guys think I could get away with square tubing made of a hard aluminum alloy? In addition to the difficulty with working steel, it's going to weigh a ton.



Craig - Thanks for the input of needing to sit low. I had noticed that, too. I'm only about 5' 10-1/2" tall, and with the seat just sitting on the floor (with the side mounts attached), having the seat in the second-from-the-lowest height addjusting hole has it close to the right height. Speaking of which, it's been so long since I've driven this car that I don't remember how high the seat was. When sitting in the seat, what kind of line of sight should I have? Should I be able to see any of the top of the hood? Or looked at anouther way, with my helmet on, how much room should there be between the top of the helmet and the roof?

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[craigawoodman]

Cloud,



Even though I am assuming you are going to have a harness (you also need a hole in the floor and a backing plate under the car for the eye to connect the lower 5/6th leg of the harness), my answer would be as low as possible while still being able to place the car. This will lower your centre of gravity, but also give your helmet clearance (another 2" on top of your head). If I have my visor up, it can touch the sunshade sometimes. There is bugger all clearance between my helmet and the roof (sunroof car).



My seat is in the second lowest mounting hole, as it cannot go any lower. You may have to play with the seat mount to also get the right distance between steering wheel and pedals. Also, clearing the handbrake may be an issue (it is for me in a RH drive car).

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[Dubai944]

Dont forget you can use the seat mount plates both ways, so the bottom flange can be outboard or inboard of the side plate. might help with lining up holes and avoiding bolts into the floor mounts? You can also use thicker plate and recess the bolt heads for the floor mounts.

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[Cloud9...68]

[quote name='Dubai944' timestamp='1363304187' post='140017']

Dont forget you can use the seat mount plates both ways, so the bottom flange can be outboard or inboard of the side plate. might help with lining up holes and avoiding bolts into the floor mounts?

[/quote]

Yes, I had that same thought. My plan is to build a mock-up of sorts - I'm going to mark the exact relation between the two brackets when attached to the seat (after determining the most advantageous orientation of the brackets against the sides of the seats, as you point out), remove the seat, and then connect the brackets with slats of wood, maintaining the exact distance between the brackets. This will allow me to situate the brackets on the floor without the seat being in the way of my line of sight, allowing me to figure out the best type of adapter I need to build to allow mounting of the seat.

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[Dubai944]

I know what a nuisance it is. All this just to sit in a car..lol.



I like the old Formula Cars where you chucked in a garbage bag full of two part foam and sat in it till it set. Instant seat that fitted perfectly.

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[MC968CS]

I have factory recaro M030 seats which I think are recaro spg seats. I am 6'2" and fit fine with a helmet. Maybe the factory solution will provide some insights for you?

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[flash]

if i ever do this again, i'll almost certainly run a beard (no joke) again. at 13lbs, it's hard to go any other way. they're designed for off-road, but i used them in the mgb and loved them.

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[Cloud9...68]

Maybe I didn't give Beard enough of a chance, but in looking at their web site, I didn't see any seats that looked much like road racing seats - the ones listed just look bulky and hefty, most are upholstered in vinyl, their weights aren't listed, etc. Like I said, maybe I should have pursued them further, but I know I fit in a Sparco Evo, so that's what I went with.

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[flash]

it's all about your butt and what feels good to you.



the beards don't look like road racing seats, but they work very well. i came at it from a different approach. i looked at the idea that off-road racing is much more abusive, and you really get tossed around. i figured that a seat that held me there, without compromising my back, would do very well in a road racing situation. as for weights, i actually had to go and see them myself to weigh them. regarding the bulkiness, they fit easily into an mgb.



with sparco, like recaro, i think you pay a lot for the name. i'm not saying they aren't a great seat, and maybe even better. i'm just saying that there is a pretty heavy markup.

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[Cloud9...68]

Makes sense that an off-road seat should stand up very well to abuse. My Evo's were year-end close-outs, so I got a good deal on them.

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