Iva Series 3

[dlovettuk]

I've acquired a barely started series 3 with mostly new/reconditioned sierra parts from a friend. I'm wondering whether there's any structural reason, once built, that I wouldn't be able to get this through an IVA. I've had a look at the IVA manual and can't see anything obvious but would appreciate any thoughts. My other option is just to use it as a track day/ sprint car but I'd like to get it on the road if possible.

[Steve Walker]

I've acquired a barely started series 3 with mostly new/reconditioned sierra parts from a friend. I'm wondering whether there's any structural reason, once built, that I wouldn't be able to get this through an IVA. I've had a look at the IVA manual and can't see anything obvious but would appreciate any thoughts. My other option is just to use it as a track day/ sprint car but I'd like to get it on the road if possible.

 

Somewhere recently I've seen a thread (either here or on locostbuilders) mentioning a fail (I think it was on an S7) as the tester didn't like the monocoque design and wanted to see box section to stiffen it. However, I don't know if this was a one off or not as there hasn't previously been a problem with SVA and I don't think think IVA changed anything that would affect this.

 

I'm sure there will be a few more series 3s coming up for IVA, so I'd just wait a bit and see what people report.

[Steve Walker]

Whoops, just spotted it a few threads down this section of the forum!

[dlovettuk]

Whoops, just spotted it a few threads down this section of the forum!

 

 

Thanks for the info. I saw the s7 thread but wasn't sure of the differences. I noticed the IVA is very specific about seatbelt mountings so this may require box section.

[Steve Walker]

Thanks for the info. I saw the s7 thread but wasn't sure of the differences. I noticed the IVA is very specific about seatbelt mountings so this may require box section.

 

The seatbelt mountings always required spreader plates, box section or similar, there's no change there - IVA may be more specific in some areas, but in practice most is the same as examiners were already requiring. The "monocoque problem" seems to be a new thing though and it'll be interesting to see where it goes. Prehaps your best bet would be to try and talk to the examiners at your local test station and see what they have to say - they should be able to say if there is a problem and suggest solutions that would satisfy them.

[Guest Sharky]

Steve

 

Sorry to hijack the thread, but is the seatbelt problem confined to certain marques of RH?

 

I am building a Zero which is a stainless box section chassis, so will this be OK or will I have to do some fabrication of some ilk?

 

Also, while we are at it, I have seen threads somewhere on here talking about a problem with seat mountings direct to the floor pan - do I need to run angle underneath the floor and seats as load spreaders?

 

Again, sorry for the hijack.

 

Sharky

[Steve Walker]

Steve

 

Sorry to hijack the thread, but is the seatbelt problem confined to certain marques of RH?

 

I am building a Zero which is a stainless box section chassis, so will this be OK or will I have to do some fabrication of some ilk?

 

Also, while we are at it, I have seen threads somewhere on here talking about a problem with seat mountings direct to the floor pan - do I need to run angle underneath the floor and seats as load spreaders?

 

Again, sorry for the hijack.

 

Sharky

 

It's not a problem at all. It's a feature of the monocoques that because they are formed of folded and welded steel or stainless-steel, the positions that you would want to mount the belts to are thin and a bolt would be likely to pull through - therefore spreader plates are needed to distribute the load over a larger area. There's nothing wrong with that and the plates/angle were provided as part of the kit (or at least they were with my series 3). Where you have a chassis, it will probably be designed so that strong mounting points are included as part of the chassis - I don't know about the zero, but would expect that this would be the case.

 

On the series 3, the floor is just flat plate with no additional support, therefore it was necessary to include angle (in my case welded frames), both to spread the load and to transfer it to the rigid areas. I don't know what provision has been made on the zero, but as there is a chassis, it would probably be easy to weld additional rails to cross the points where the seat bolts will be and ensure a very solid anchorage.

 

SteveW

[Snapperpaul]

I got my S3 through the SVA last July.

Modifications i made specificaly for SVA were to weld a tube across the roll cage behind the seats at a bit higher than the specified seat belt mounting height. The rear seat belt mounts to the rear of the car but goes over the cross bar which is now higher than the original mounting position.

I ran two reinforcing angle irons from the rear seat belt support bar to the roll cage, 1 from the seatbelt mounting point and 1 from the end of the seat belt mounting bar.

I put plates under the roll cage where it rests on the boot floor and as well as using the u clamps to bolt the cage in i had two crush tubes welded in the the down tubes of the roll cage and used M12 bolts through that and the boot sides bolting through the suspension angle with spreader washers.

The inside seat belt mounts had captive nuts welded to thick plate so i made similar for the out mounts.

Seats were bolted through angle iron under the floor which go fore and aft connecting to the rear lip and a cross section of angle forming a rectangle for each seat connectint at the front to the gearbox support member.

A spreader plate was made for the diff mounting bolts which go through the boot floor.

 

The steering column support hoop was to flimsy so i ran 2 3mm thick peices or bar from the column bolts to the rear of the scuttle/bulkhead and used spreader washers again.

 

The pedal box was flimsy so i added another peice or 3mm bar from the scuttle over the pedal box to the mounting plate.

I then added at either edge of the mounting plate 2 peices of thick threaded bar to the bulkhead, it still flexed so i added a cross peice of angle, now solid.

 

I know that some have run two peices of angle from the boot rear down either side of the tunnle top this adds strength and also provides a small tunnel to run pipes and electrics, i used the side box sections.