Taking height out of your seats...question...

[BGCarrera32]

Howdy...

While trying to remove "Z" height out of my seats for additional helmet clearance, I started playing with my mounting options a little. One thing I concluded was that if a factory seat or an aftermarket seat is bolted directly to the floor, it would be left-of-center to the steering wheel (i.e. steering wheel is no longer centered in front of you). My conclusion was that regardless of the seat, due to the width of the shift tunnel hump in my '84 911, whatever seat I go with the seat bottom can be mounted no lower than the shift tunnel top. Can anyone confirm this? It seems as though you are dependant on finding a seat with very low bracket mounting surface-to-butt pad height to remove overall height so a helmet would clear... I am 5'8" with a long torso, and have a sunroof coupe. Currently looking at an Evo 2 seat...

Having the wheel a 1/2" off center will drive me nuts...

Thanks for any additional insight...

Brian

[IROC]

I don't know if this is the direction you're heading, but when I installed Evo 2s in my '76 (non-sunroof coupe), I used the factory sliders along with the steel Sparco seat mounting brackets. This ended up being way too tall. I was sitting higher than a stock seat.

I ended up doing away with the factory sliders and mounting the Sparco brackets directly to the factory seat mounting brackets. I had to drill some new holes and of course I have no fore/aft adjustment, but I'm the only one that drives the car anyway.

With this bracket mounting and seat mounted in their lowest settings in the Sparco brackets, I sit very low in the car. Works great.

I probably have a digital pic at home somewhere....

Mike

[85eurocarrera]

Brian, if you had not told me I would not have of known.

Are you saying if you mount the EVO 2 seat at the tunnel height you wont have room? What if you slide the sun roof liner out of the way for track days? This will buy you some room as long as your seat position is under the sunroof which I suspect it would be.

Joe,
sitting slightly to the left of center.

[BGCarrera32]

Hey guys...thanks for the input.

Well, from what I have seen it doesn't look like you gain much just changing the seats, unless you sink it in down to the floor pan. And then you sit off center...

I just don't want to spend $600 on a seat, drop it in the same location on the factory brackets and find out I gained no additional clearance. What is frustrating is that neither Sparco or Recaro offer PDF documents with detailed dimensions on mounting locations, etc. I'd like to do my brackets and welding before I install the new carpet and trim.

AND if anyone has PHOTOS of their brackets, etc. I;d sure like to see them, even if from a different vintage of 911. TIA...

-BG

[Craig Stevens]

BG, I am addresing this problem with the Corbeau CR1 seats that I just purchased. The CR1's sit higher than stock seats. I do not want to cut & fabricate new mounting points. So I recline the seat & sit lower in the Cr1 seat than I do with the stock seat. I will just have to get use to the new position before my next DE. If anyone has a better suggestion, I am open to hear it. This is a beget situation. I wanted a 6pt harness, so I needed new seats. The CR1 seats are well made seat but the cloth attracts lint like a magnet, & it just fits you differently. I got the fat- boy seats & there is plenty of room. Good luck in your search. Craig

[Chuck Moreland]

The factory seat position is not centered on the steering wheel. The seat is skewed slightly to the center of the car. Sounds like your solution is about the same.

[BGCarrera32]

Originally posted by Chuck Moreland
The factory seat position is not centered on the steering wheel. The seat is skewed slightly to the center of the car. Sounds like your solution is about the same.

No offense but I disagree... in fact if you look at the bracket near the door you can see its bent out and at an angle a good inch away from the unit body. Now, it may not be perfect centering, but its much worse with the brackets removed. When I ground out the factory brackets with a death wheel and then just shoved the factory seat down in there almost to the floor board, the seat was shoved way left (closer to the driver's door). If only that tunnel was an inch or so narrower...but I'm not going there...

[BGCarrera32]

bumpin'

[Teutonics]

I had my brackets lowered on my carrera, and they are below the tunnel. I gained a full inch of helmet room with the factory seats. However, the tunnel had to be "massaged" at the very rear of the seat travel point to keep from interfering (you can barely see it at the far right of the pic below).



Let me know if you have any questions, I'll try to help.

[BGCarrera32]

Thanks Allen...looks like maybe it was massaged with a sledge...?

-BG

[Teutonics]

I prefer not to think about it, but yes a specialized blunt heavy instrument was repeatedly utilized during the precision modification procedure.

It's really not as bad as it sounds, and after a re-coat of black spray paint, it isn't very noticable unless you are looking for it. The necessary added clearance at maximum seat travel was only a 1/4" or so.

[Russ in VA]

I have a vintage 80's set of recaro's in my car mounted on the factory seat brackets. It lowered the sitting height about and inch I'd say. Guess the seat rail mounting plane to bottom cushion dimension is where it differs. Don't know if this helps.

[BGCarrera32]

Originally posted by Russ in VA
Guess the seat rail mounting plane to bottom cushion dimension is where it differs. Don't know if this helps.

Yeah, that does make sense. That's the biggest thing I'm having trouble with. Everything is just too darn high. Boy how I wish I had a 911 without the sunroof...I'd pick up a good 1 1/2" right there...

[atr911]

I ordered the floor mount brackets so I wouldnt' have to worry about seat height.

I don't mind cutting and pasting though as I'll be the only one driving the car and don't plan on keeping it anywhere near stock

Adam

[Jeff Alton]

BG how tall are you?? I had the same problem with my 84. Bought a Sparco sprint and fabbed up some angle iron adapters. Put in the Sparco sliders and voila,,I fit with my helmet! Of course, I am only 5' 10, but I could still lower the seat atleast another inch and a quarter. I just bolted the angle iron to the in board sides of the stock seat rail consoles.

Hope this helps, Jeff

[Pete James]

Both my son and I are over 6'3" and long torso'd. We both touch the cieling now and helmets would be impossible. So far Tuetonics solution looks the best as we need to gain real height from the mounts and also from less thick seat cushions. Thanks everyone for the quick responses. Pete

[rfw 911]

I had this problem in my Euro Carrera,
I am 5' 10" and with the helmet on I had to srunch my
butt forward to keep from ending up compresing all
of the disks in my neck! Needless to say this didnt
make having the harness on a worthwhile thing since I could slide all around.

On my stock seats between the mounting tracks and the seat bottom I found that there was a stack of 2 aluminun spacer blocks
that are approx. 3/4" each. I removed them and re-installed the seat without them, I had to get some 8MM (?) grade 8 bolts that were only about 1 1'4 long. It was a bear to get in there with a
socket but the end result was well worth it. I still have to do the other side. I think the way to go is probably to use allen bolts so there isnt any issue with the sockets.

Good Luck!

Rich
77 Carrera 3.0 (Euro)

[BGCarrera32]

You had the optional riser blocks for short people installed. I found those under my drivers seat and yanked them out too...

[jyl]

I thought it was interesting that the Allen bolts securing my seat rails were metric 8.8 which is actually a bit weaker than regular grade 5. Then I looked up the shear strength of a 1/4" grade 5 bolt and saw it is something like 3,500 lbs. 6 bolts x 3,500 lbs/bolt = 21,000 lbs = 10 g x 200 lb me. Enough strength, d'you think?

[Wil Ferch]

I didn't re-check or follow your math, but....

In general...Euro 8.8 is commonly taken to be equivalent to US grade 5.

Shouldn't be a problem...

--Wil Ferch