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jwscab wrote:Doesn't the b4 have a 25 degree kick up? Which means 25 degree blocks on a standard truck nose give you 30 degrees caster?( they are 'straight up')

Yes, unless your turning them around (bunch of us did with them to start) for a better camber link angle.

it shouldn't matter right? the camber link angle would change, but the caster would still be 25, the spindle and arm pins are drilled perpendicular(90 degrees), no? the location of the spindle would be more forward though.

No a 25 is a zero. So on a 30 degree kick up, it will be 30 degree castor no matter what side its mounted on.

Lets just do this:

Mounted normally:

30 = 35
25 = 30
20 = 25

Or you could do this:

30 = +5
25 = 0
20 = -5

Or mounted backwards:

30 = 25 (-5)
25 = 30 (0)
20 = 35 (+5)

OK, good, Sean, you and I are on the same page. That's how I'm seeing it in my head as well.

so you could use B4 20 degree blocks on a 30 degree nose to substitute for the hard to find rc10 25 degree blocks.

Hmmm, I don't see an associated part number in tower for 20 degree blocks. I'd sure like to try them!

Found it, 9592!
I'll post side pictures of each set up (25 and 20 degree) when my parts arrive at the end of the week.

jwscab wrote:...the location of the spindle would be more forward though.

This is what I believe gives the lower caster effect when you reverse the 30 degree B4 caster blocks. It's kinda like the reverse of using a trailing axle steering block.

jwscab wrote:OK, good, Sean, you and I are on the same page. That's how I'm seeing it in my head as well.

so you could use B4 20 degree blocks on a 30 degree nose to substitute for the hard to find rc10 25 degree blocks.

Its going to be wider than RC10 25 degree castor blocks.

Orange wrote:

jwscab wrote:OK, good, Sean, you and I are on the same page. That's how I'm seeing it in my head as well.

so you could use B4 20 degree blocks on a 30 degree nose to substitute for the hard to find rc10 25 degree blocks.

Its going to be wider than RC10 25 degree castor blocks.

Yes it will be wider, but just by a tiny bit. You can still use the same turnbuckles. Isn't wider better , I think that was Pontiac's slogan back in the 60's. Wide track baby!

It depends... if you are making a bone stock rc10 wider, I don't think its better. As a matter of fact at Cactus, I started out wide and the more I narrowed it back down to stock, the better it got.

Agreed, I was making a broad statement. The front track after the b4 caster blocks makes the front just a tad wider than the B4 itself. Also makes the front a bit wider than the rear which could effect the geometry and track manners. I won't know till I get some wheel time.

Oh muh bad... "Isn't wider better"

Thats what she said!

Orange wrote:You could have used B4/T4 steering blocks with T4 Axles like I have on my Klien arm car (Shown with 30's, I have since changed them to 25's):

At full steering lock do your outer rod ends bind?

No. Everything is good. Car ran like a champ. I only used that car at one race though, but with 25's on it. Its been a few years since I ran it. I would have remembered that if it did. I also have RPM steering arms on it though.

Orange wrote:No. Everything is good. Car ran like a champ. I only used that car at one race though, but with 25's on it. Its been a few years since I ran it. I would have remembered that if it did.

Thanx! I forgot mention an important detail. At full steering lock "with the suspension compressed", do the outer tie rods bind? Also do you recall the length turnbuckle you used on the steering? Thank you again for your help!