Well, I bought this little LBC with a SBF...

In reply to Winston:

There are lot's of detailed walk throughs on shortening a miata steering rack. Start with the power rack though.

MG_Bryan wrote: There are lot's of detailed walk throughs on shortening a miata steering rack. Start with the power rack though.

I have a power Miata rack as well as Miata spindles and brakes... the problem is that they're front-steer, and it looks like I'll be going rear-steer with the Spit to keep the V8. I could probably pull an '80's Corolla rack and spindles from the junkyard without too much trouble, but I would rather not have to adapt a McPherson strut to accept an upper ball joint if I didn't have to. Oooh... maybe Honda! Those have upper and lower front control arms, right?

Doh. You could use a RHD miata rack. No thoughts on spindles though

Edit. Saturn S series racks are supposed to be rear steer and pretty light weight. I don't spend enough time with front wheel drive to know what has spindles that will work for you. LocostUSA can probably help you out though

Honda front knuckles are tall which would make it tough to mount the upper control arm.

FWIW, there's no reason you couldn't swap the stock spindles side to side, thus pointing the steering arms rearward. For that matter, the steering arms bolt on and could be moved to point them rearward, but I think that would probably interfere with the calipers.

The Dodge Omni rack is supposed to be the best rear steer rack around. Have not used one, though. But honestly, I'm thinking you may have more issues with that than you'd think. Follow me on this: you need to have the steering tie rods level all the way across and parallel to the lower control arm to minimize bump steer. For Ackerman to be correct on a rear steer setup if you look at it from above the tie rods have to sweep back, i.e. the inner tie rod pivot has to be ahead of the outer tie rod pivot. That means the steering rack will have to be very close to the front crossmember and above the frame rails. Which means it will be fighting for real estate with the crankshaft.

You might consider a different approach: build a conventional or 'parallelogram' steering with two idler arms. Sort of like this:

With that system, you can put the center link height pretty much anywhere you want it and that link can be shaped in a lot of different ways, meaning you won't have to move the engine much if any. Once that is done, you can use the Spitfire rack to move one side of the steering (probably easiest on the drivers' side) and the linkage will move the other side. Of course I'm oversimplifying, just tossing out an idea.

Sorry Im late to the party...did no one mention F20C?

Did you say F20C? http://www.britishv8.org/Triumph/JoeCurry.htm

Thanks for the ideas, Curmudgeon. One thing to keep in mind is that this Spit has a completely custom tube chassis (I did mention that, right?). Things like crossmembers aren't necessarily where they would be on a stock Spitfire. You're correct about the engine sitting low in the chassis, so it could very well interfere with proper rear-steer rack placement.

The rear steer idea may yet work, but I will certainly consider the parallelogram steering. Good thinking.

Can I really swap front-steer spindles around? I thought that there were all sorts of issues with things like kingpin inclination, caster, and other arcane stuff like that. Time to pull out my copy of Chassis Engineering...

4cylndrfury wrote: Sorry Im late to the party...did no one mention F20C?

We're back on "make the V8 work" for now :)

Check out why the control arm is so out of level. I have a 79 that I cut the front springs on to lower and the control arm is level. I think you have something else going on there.

As for the rack being out of square or 90deg to the wheel, the arm that the outer tie rod attaches to bolts to the spindle. You could fabricate a new arm to replace it and eliminate that and bump steer. Doesn't help with the linkage.

Custom fabricated front spindles are not rocket science, stock car folks use them all the time. Just have be sure that they are strong/tough enough. For years many Toyotas used a system with a stub axle running in a bearing/seal housing that bolts up to a flat surface on the upright. It's proven, tough, cheap, and available everywhere.

Carter

In reply to porksboy:

Yeah, I think that I've convinced myself that the suspension is compressed due to the weight of the V8. That explains the angle of the steering rack tie rod as well as the lower control arm. This was mentioned by someone earlier in this thread, and after looking at the car last night I think they're correct. The wheel gap looks normal because the custom chassis is dropped in comparison to the stock chassis so that the V8 can fit under the hood without cutting. At least that's my current theory.

Smart thinking re: the bolt-on steering arms! Though that would make the steering slower :( Still, that may be the best solution.

Some earlier model Spitfire front uprights already feature seperate removable steering arms. Look for Mk I (also called Spitfire 4).

Swapping the uprights side to side won't change the KPI. Flipping them upside down will. Been a while since I actually gazed upon them but I thought all Spitfire front uprights had bolt on steering arms. But I've been wrong before and will be again, just ask my ex...

About the rack position: on a stock Spit the center of the rack is right over the lower control arm front bushing. Dumb design, it points the steering tie rod in the wrong direction which makes for really weird Ackerman, the outer wheel turns further in than the inner (should be the other way around) and at big steering angles this can yank the wheel out of your hands! That's why I repositioned the Abomination's rack.

Here's the stock Spit layout. It is possible yours might be a bit further forward.

Another shot:

Looks like the MkIV Spitfires have them too.

Here's one bolt, the other is obscured:

Edit: Curmudgeon, thanks for the info and pic. That certainly helps because I have no idea what the stock setup looks like. I'll get some pics of my front suspension setup this weekend and post them up. You can probably see from my eariler pics that my rack is pushed farther forward than stock. This was done in order to clear the crank pulley on the 5.0. EDIT: NOPE, looks like I was totally wrong. Page 2 has a pic of the passenger's side and the rack clearly sits directly above the front LCA bushing. Wow, I guess this is another example of how eye-witness accounts are untrustworthy because your brain tends to make stuff up!

Aha. The other bolt (just barely peeking out under the control arm) is actually the nut for the stub axle. Do you think it's possible to sneak the rack in between the balancer and the front cover, the way it's done in the pic of the Spitfire? If the engine is scooted back an inch or 3, those together could get the steering where it needs to be without resorting to rear steer, etc. You only need 3/4" or so clearance.

I don't think that there's much room between the balancer and cover, but I'll check.

There are crank pulley spacers available for Ford 302s if that helps in regard to what Curmudgeon just suggested.

You could address the slower steering with a faster rack. They are available many places. The 1500 Spitfire has detachable arms.

Maybe the oil pan could be notched at the front for rack clearance. As I say, it won't need much. You might be able to get enough clearance with a ball peen hammer. Of course be careful of the whirly bits inside!

I once saw a picture of an oil pan with a tube running through it for a steering center link.

If you plan to go through with all this, I suggest shortening the rack as well. I don't remember the exact dimensions but I know it helped with the steering a LOT. You shorten a Spit rack the same way as a Miata, the only real difference is the Spit rack has a bronze bushing at the outside of the right side of the tube.

I am really late to the party but why am I thinking of a flat6 out of a Subi?

Na form 200-250 HP add boost and 300-400 hp with out a problem depending on the $$$$ available. Really no issue with hood clearance (it is flat) The question would be the width. IT sure would lower the cg and take some weight off the front as well.

I have no idea about motor mounts, transmission, engine management but hay It sounds like a really cool car to me.

Very wide engine. And exhaust ports tend to be where the frame is.

Hotlinking still not working for me. Here's a link to something really crazy involving a GT6 and a 620 Datsun mind meld. http://forums.24hoursoflemons.com/viewtopic.php?id=12787

Curmudgeon: I'll certainly check into what I can do for additional clearance at the oil pan. Not sure I'm ready to add a tube through it, though Thanks for the tip on shortening the rack. I'm planning on running the whole suspension through Wishbone to see how the geometry looks. Also, interesting LeMons link!

Dean1484: Pick two: (1) Front suspension (2) footwells (3) Subaru engine. Good thought though, that crossed my mind when I tried to think of short engines that are readily available.

If I were to do some crazy engine swap into a Spitfire/GT6, and didn't want to use a rotory, I'd probably go with a GM V6 (2.8 to 3.1) or a Rover V8. Both are pretty low and easily had with a manual transmission.

Tegler - the guy who built the previously linked set-back Spit 6 - also built a MGB GT with a GM V6 a couple of years ago. He also has a stock GT6 in his stable. When he had the engine sitting in the garage, he got curious and did some measuring and was pretty certain the V6 would fit under a Spit bonnet w/o difficulty.

I have pictures of a GT6 with a Rover V8 under the bonnet, but no information on how it was done or detailed engine bay pics. In the pics I do have, the car looks stealthy.

There's probably enough room under a GT6 bonnet to stick pretty much any pushrod V6, the 60 degree GM would be cake. But that's not the ideal engine for the car IMHO, it's just too pedestrian. It cries out for something more radical. But when you get into the OHC engines the fit problems begin.

Turbo? In theory, the short V6 engine would allow a turbo to be mounted ahead of the engine... which actually might simplify exhaust piping a bit.