I have been doing some measuring and am curious on how much room I should leave between the wheel and the body.

If I build a book chassis I should have about 3 inches but If I build a +4 I will have about 1 inch.
Is this enough room or do I need the 3 inches?

The real clearance issue is the distance between the inside of the tyre and the trailing links of the rear suspension . so it will be important to have the wheels and tyres that you intend to use as you are laying out your build . (or at least their paramiters ) some builders have used rose joints and narower brackets on the body to give more clearance for the tyres . I know of a couple of builders here (in Australia) who had to have some coustom wheels made at great expense because of a lack of clearance. I hope this is helpfull
Best wishes
Iain

Ohh, I should have said it was IRS. Sorry about that. So there will be no trailing arms, just A arms (well one will be a N) in the back.

Thanks for the tip though, I realy want to get the rims first but the rim money pays for the begining of the chassis build. Oh the delema

Hi Spotty
well the same things are important that the wheels and tyres do not touch the body or chassis as they move up and down , Can you get a wheel of the same size / offsett as those you intend to use or even borrow one ? even if it is a bit different if you know what the diffence is then you can check your clearance ,any way a bit more for you to consider
best wishes
Iain

I would love to get just one rim to see if it would work but they are 15x7 with 0 offset so finding them too borrow is tough.

It looks like I will just have to build a stock chassis. I was hoping for the extra room but whats 2 inches in each seat area? Besides, now I dont need seats with leg support

Hi Spotty.
You may be able to gain some room width wise in your cockpit by slimming down the transmission tunnel especially as you are going with IRS have you considered having some steel folded to make the trans tunnel you could very easily get 2inches that way maybe even more .Remenber that with IRS you do not have to allow for movement of the drive shaft . a folded and welded steel tunnel will contibute as much to chassis stiffness as the book design. just a thought
best wishes
Iain

Hey, thats a great idea! The drivshaft is pretty small too. I'll just have to put in some bracing for the just incase it breaks moment.

Thanks again, I think the book chassis should do fine.