Yolo7, can you compare the thickness/heights of the seat bottoms, between stock and those Corbeaus? The Evolution specs out at just 2.5" under your butt, but I'm curious how that compares to an OE seat with 100k miles on it.

 

I guess I'm wondering if just swapping to the Corbeaus would give you any noticeable head room, before resorting to cutting out the pedestals.

 

They won't. When you sink into the stock seat, your butt is below the rails, that doesn't happen with aftermarket seats, or at least not with corbeau seats. You will not gain headroom with an aftermarket seat unless it's side-mount style. You have to cut the rear perches out and mount the bracket to the floor.

 

So I have set the Corbeau seat on top of the rails and I clear with the helmet and some room. A lot better than the seat The car came with. I know the mounting plate will be a litter higher, but it’s worth the shot. I’ll find out soon enough because I order the Planted Mount last night.

I add again, that the seat my car with isn’t the OEM seat. So I can’t say how an OE would would compare. Below are pictures of the seat the car came with. You can see the outboard slider does not sit flush with the seat frame. This, along with the relocated mounting points for the in board slider are how I determined this.

I really don’t know how it’s all going to work out. While being taller is a perk for a lot of things, it sucks when you like sports cars. Especially the smaller Japanese types. But I have to give it a try. I’ll cross my fingers and let you know.

 

 

Yes. Your floor is original.
Factory rails do not have 90 degree angled attachments. It would have made fabricating seat rail adapters way too easy.

 

Well I'm glad I sub'd to this thread. The only reason I was looking at aftermarket seats was to get my butt closer to the floor. If I have to remove the rear floor mounts to get another inch of headroom I'll do it but keep the OE seats and flatten the rear of the brackets. Drilling holes through the floors really skeeves me out though. Wonder if the sheetmetal floor is strong enough to just braze mounting studs onto.

 

Are you going to be the only driver? Seems I read this won’t be on the street. If so, lose the sliders/flat brackets and bolt to the floor. Remove the factory rear humps, use temporary shims(I used small plywood squares) to prop the seat to the perfect sitting position, then fab your own brackets. I took a quock look at your 5.0 build and you for sur have the skills,tools to do that. That’s the best way to get the helmet clearance. You may find that the steering wheel placement may not be perfect so this would be a good time to consider a removable mount that is easy to adjust with spacers.

Since you you are close by, you are welcome to a cage I have that was cut out of a wrecked Pro7 car. You can use the back half for a roll bar. You are also welcome to some out-of-date cam lock belts I have. Not sure if you can use them for auto-cross or not but they are in fine shape and you could at least use them for mocking up. Happy to give them to a fellow NorCal first gen builder.

 

I used washers that are about 2" in diameter and bolts that came from a seat belt mounting kit. Bolt went up from the bottom with one washer, then inside the cabin another large washer and nut. The seat bracket went over that with another nut and washer. That gave me the clearance to slide the seats all the way back without getting caught on the carpet.

 

What did you do to the rear mounting tabs on the seat bracket to bolt flat to the floor? Just bend them flat?

 

I cut them right off of the corbeau bracket with a grinder and drilled a hole on each rear corner of the bracket to use for mounting instead.

 

Mmmmmmm... smaller Japanese types. good luck. I'm subbed as I need all the head room.

 

https://www.cobraseats.com/seats.html?pid=24&cid=3

Compatable with oem lap belt
Looks mint
Not sure or price

 

Thanks for the info. Looks like it’s a couple hundred more but I like how it’s a side mount. I’ll see how things work out once my new bracket shows up tomorrow.

 

Let us know how you go. Pics of the fitment too?? I'm finding it really hard to find a seat that does cost a arm and a leg, will give me more headroom and work with the oem belt.

 

Here's photos of my Corbeau installation.
https://www.rx7club.com/build-thread.../#post12261236

 

Okay, so I finished putting the seat in. There was a lot of good information shared by others, some of which was very true.

To start, the Planted seat bracket is a really nice piece. The four mounting legs are a match to the car and bolts in easily. The two rear leg angels are a perfect fit to the car. The front outer was a scant off, and the front inner leg angle a little worst. Once you torque the front down, the bracket gives just enough to match the outer angle and bolt flat. I figure this should be good enough for my application.





The front inner leg angle a little off.


I ended up using the Corbeau sliders. I may get rid of them later, but decided to use them to aid in the ease of installation. Because I require the seating position so far back, the seat bracket is about three inches short of being able to directly bolt to the rear seat fastener location. If eliminating the brackets, I could probably get some ¼” steel stock and use it as a spacer/extender. I think I would only gain about another ½ to ¾” if I did. I don’t think this would be too hard to bolt in, there is enough space between the seat and rear cross brace for access with the seat tilted forward.
The sliders lined up perfectly with the Planted bracket. The Planted brackets allows some side to side movement to position it to your liking, so I moved the seat as far inwards as I could to get me further from the roof side rail. I picked up some new hardened bolts and washers from the hardware store and it all went right in.


The slider in my seating position.

The seat bolt whole is a bout three inches off from the bracket for direct mounting.

The bracket is slotted to allow left to right adjustment.

In the end, I think I gained around ½ to ¾” over the seat I had. I am having to recline the seat back further than I wish. Depending on my posture, I can completely clear the roof, but it take a little bit of slouching. I like the way the seat feels, so I can live with it to start and change it later if I want.

The pedals are easy to reach. But the steering wheel needs to come closer to me. And the shifter is a tad on the far side. If I hadn’t done the V8 swap, the stock SA shifter location might not work so well (Ford T5 sits a few inches more rearward). So I will be looking for a new steering wheel with an extension and maybe a quick release. If anyone knows a semi affordable adapter/wheel I’d love to hear from you. I’ve started browsing the Grant product line.


The finished product.

Knees hit the steering wheel.

Distance to the cross member with the seat at the rear most adjustment.

I think I could get a enough access to direct mount if need be.

Distance to the cross member with seat back in driving position. Taken from the inside where the cross member is raised for driveshaft.

If anyone wants some other specifics or photos I can try and get them for you.

 

How tall are you?

I'm 6'4''. with a lot of it being in the legs and with the standard setup of the car it was a struggle, knees caught on the wheel and it was too far away if I set the seat so that my legs felt right.
I ended up getting an eBay special deep dish steering wheel, I think 350mm (14"), this had two benefits, the first was that it pushed the wheel closer to me, which meant that with my arms fully outstretched then my wrists would rest on top of the wheel with my hands able to drop behind it. Which is ideal for me.

Being closer to me with a reduced diameter also gave me leg room as it pushed the wheel past my knees. I'll probably upgrade this wheel to something better quality in the future, but for a cheap purchase just to test it out, its worked really well.

Headroom I use FC seats and my head just clears the roof, if I have any kind of hairstyle that isn't flat to my head then I can feel it brushing the roof! I think I would struggle with a helmet so that's something that needs addressing.

But for your knee / wheel issue it might be worth getting a cheapo ebay wheel just to experiment first.

 

I'm using a grant wheel with a moderate dish to it, plus an extension to bring it even closer. You could use a quick-release instead of an extension as both will give you that extra 2-3". I forget the diameter, if you go too small you won't be able to see the gauges.

 

I’m 6’2”, and if you asked my wife (who’s always right ), I’m taller in the torso.

I agree with then idea that extending the steering wheel out a few inches is more important than diameter. It’s gets the wheel beyond your knees. Just need to locate a hub adapter.

 

An issue I've found with the smaller wheel is that as Chuyler mentioned it can be harder to see the gauges.
Speedo is fine but oil pressure I have to **** my head slightly. But to be honest its rare I look that more than the odd time when driving.

Also with the smaller wheel its a bit more work to turn it, especially at slow speed, but also going fast. Now I'm used to it I don't find it too bad, power steering + rack & pinion would be nice, but hey ho.
The upside is that I can fit in the car comfortably, which I sometimes struggle with on the older Japanese cars.

 

Shouldn't thread be moved to the race tech section?