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yeah im going to mould off another GTR quarter I have here.

I suprised how much crap is there!

not mine I hope, I was expecting it back soon :P

Random questions....

Wheel base/track is free.. Yes?

Wheel width can't be wider than 10"?

no and no!

basically this is a very different style of race car compare to what pretty much everyone with a skyline does. Most of our cars would be considered "improved production" except that they require 2x 28mm air intake restrictors. As a result almost no-one builds legal improved prod skylines ( I know of only 3).

But sports sedan are much more serious. the actual chasis in a normal ss is all spaceframe, the rules only require the same "external shape" and even that seems to be pretty liberal. So track is anything you like, as long as the wheels fit inside the bodywork - and the bodywork can be up to 100mm wider per side than standard - and assuming Brad is using gtr shell as the template that means 200mm wider than standard GTR.

And as demonstrated here the chasis underneath the bodywork does not have to be anything like factory - spaceframe is the go.

Wheel width is definately not limited to 10", that would be considered on the very small size. Not sure what the front runners use in tyres but dunlop have up to 325 width for 13" rims.

the big "but" for skylines is that you can only run 2wd under these rules. If you want to run 4wd there are a whole lot of special rules to make sure you can't be competitive outright including you must keep the factory floorpan, and you must run the factory block. To me this means gtr is the only 4wd which would even have a chance in 4wd ss. I'm building a 4wd sports sedan but it is anything but guaranteed that it will be faster than this :)

Random questions....

Wheel base/track is free.. Yes?

Wheel width can't be wider than 10"?

100mm wider each side, you can lengthen or shrink the wheelbase 100mm. max width of wheel or tyre is 370mm.

Edited by Riverside Racing Parts

Not free no.

Wheel base has a 100mm+- tolerance

Track is free but the body cant be anymore than 100mm per side wider and the wheels must be under the guards so that limits track to +200mm really

Maximum rim width is 370mm

Thats my interpretation of the rules.

I've decided how the basic chassis will be constructed tonight and the rough design of the cage.

Still working on suspension geometry but its coming along.

The suspension is a real learning curve. Guys who are trying to tune suspension on floor pan GTR's are doing it the hard way. Working with roll centers and calculating instant centers etc is an art that im having to learn. I thought my GTR had pretty good suspension under it (Duncan is pretty impressed by it to say the least) but this is going to be so much better!

haha, we were all posting at the same time..

In comparision my current white GTR is built to 3d AWD rules and its no where near quick enough to be a front runner.

Brandsters GTR which is very similar to mine is still off the pace as well but has shown some speed at times.

Thinking this car will now use a 2.6L engine again.

A few reasons. First being we have recently tested a killer RB26 which is certainly something different.

If its a 2.6 I can drop some more weight 1050kg compared to 1200Kg if im reading the rules right and doing the correct math.

We currently use 2.6L engines so only need to keep one or two spare for the three cars instead of two for each capacity.

The question will be reliability making the power over race distance but im more than confident they can do it.

I can mount the engine alot better in this chassis which will help the long straight six stay in a straight line and not flex. (yes we've had them flex in the block before)

Edited by Risking

So what are your plans with this car Brad,,,are you going the play Nats or NSW stuff.

Nats are a big call...but so is the state stuff.

Can you please brace the bottom so the whole thing doesn't buckle and bend.

Neil.

Duncan and I were talking about this tonight,

Im going to play NSW stuff for the time being. Ill spend the time and money getting it reasonably competative before racing it but thats the initial goal. Ill see how it goes but I know the national series is a big ask. I may do some of the local national rounds.

I think the thing could be pretty competative, I wouldn't have started it if I thought it would be a nugget. Without blowing my own trumpet I can steer but still have alot to learn as well.

I always planned to race the white car in the NSW series but its just not feasable. its bloody quick for what it is though. I Know id be leading from the 3rd row of the grid by turn one but after that id get my arse handed to me. I dont mind loosing but I hate loosing miserably.

This will no doubt be quicker than my current car but I haven't really got anything or anyone targeted. Im more so building it for personal satisfaction and reasons I guess.

Yeah I have made some slow progress

I've been getting Duncan's production car back up and running but i've managed to do a bit.

I've cleaned up the remaining body shell and laid down the two main chassis rails. I've knotched tube and tacked them together so they are parrallel at the distance I want. I've also got the two outter rails made up that the main body will be mounted off and the supports to join the main rails and the outters are knotched up and ready to TIG in. Made a dumby hoop and front legs from 15mm OD tube that I can use as a template for the main stuff.

I started machining the uprights from billet tonight, (ill probably do one to start with to make sure it will work)

I've done a few CAD drawings of the suspension and worked out control arm angles, roll centers and everything else I could think of. Still deciding how im going to do the shock mounts. Id like rocker arm but not convinced as yet.

Im still not sure what sort of ride height the Chassis should end up with but looking over it thats governed by the wheels, uprights, suspension angles and so forth.

The best procedure to building this is not really clear to me yet, Im trying to look at it from as many angles as possible always looking into the future before doing anything.

The iritating part about this is the time i've spent thinking and designing the car I could have built the cage in my white GTR all over again. Something different though.

Edited by Risking

Actually save me writting an email.

Liam what do you typically use for steering racks??

Im almost set on using a woodward rack I have with an electric power steering pump.

I currently use a nissan rack with electric pump and it works really well, problem is the nissan racks don't have any decent mountings without using silly shaped brackets.

The knuckles on the rack are 800mm apart. So within the chassis rails. I was contempating manual steering but with an 11-12 inch rim on the front I think thats out of the question now.

I've used a Tilton pump on the GTR but planned to use the TRW pump like Dave has done with the new car.

The Tilton required an external resivour and is pretty heavy.

I used to throw a steering belt atleast once a round. Its not had any problems with the steering since the change and its so much smoother to use.

Sorry the mounts on the rack are 800mm apart. There is another 60mm of rack each side before the rack arm begins

Here's a few photos from the garage.

I built the entire white GTR in this garage but the new one is going to outgrow it and have to move to the workshop or the parents workshop shortly. I like having the garage heated and being able to work of a night time at the moment so it'll stay till I can't do anymore.

Plus the lathe, mill and machinary are not here.

The surface rust on the material is nothing, the whole car will be bead blasted and powercoated/painted depending on the final weight.

I've just finished milling up some alloy blocks with scallops taken out of them to rest the chassis rails on at the desired ride height. Those wooden blocks are not really accurate but closish representation of the rails height.

You can see where the front end has been cut off and the fire wall used to be.

Chassis.jpg

This is from the rear of the car. You can see whats been cut out of it. The tires at the front are 300wide michelins that will be the front tires.

Keen eyes will see how much has been removed from the sill panels too.

chassis1.jpg

Photo of the rear quarter, or where it used to be. There is still more material to be taken out of the internal skins around here

chassis2.jpg

Random shot of Jay cutting up the rear section.

cuttingup.jpg

Another random shot to stir duncan, He actually managed to get in and out of the R32!

Duncan.jpg

This is the cage in my other GTR, ill be pretty much replicating it ontop of the space frame

cage.jpg

Edited by Risking
I used to throw a steering belt atleast once a round. Its not had any problems with the steering since the change and its so much smoother to use.

out of interest what balancer were you using when it was throwing off PS belts?

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