Help me learn how to make a stock 1978 Spitfire handle better.

I just bought my second Spitfire. I had my first one for about a week in 1981 when someone decided they wanted it more than I did. I'll probably keep this one long enough to autoX. I've had some successful MGs and Sprites but never tried to do anything with a Spitfire. My plan is to build to the rule book. I thought about leaving the suspension stock but I know I'll never be satisfied with that.

I've been looking for on the shelf parts and haven't found anything yet. Last night I googled z-bars and camber compensators because I know that there are still successful race cars running with this mod. I haven't yet found anyone stocking such items.

So how to I proceed from here? Your advise would be appreciated.

Grae, be careful who you ask around here. They'll have you trying to stick spinning triangles in it in no time.

What year? That'll matter a bit.

Ian F wrote: What year? That'll matter a bit.

It's in the title, 1978.

In reply to Graefin10:

Doh! Sorry.

Build to what rule book? F-Street Prepared?

Ian F wrote: In reply to Graefin10: Doh! Sorry. Build to what rule book? F-Street Prepared?

Probably. I started reading the rules a couple of nights ago but haven't gotten back to it yet. I need to give the car a thorough going over before I make a firm decision. The rules have changed a lot since I quit running my D S/P MGB. That car really handled well. The best thing I did to it was put Hoosiers on it. I haven't been active since about 93 or 94.

nicksta43 wrote: Grae, be careful who you ask around here. They'll have you trying to stick spinning triangles in it in no time.

Yeah, the car that GRM built is incredible. I intend to keep it relatively stock but safe. I know I want a roll bar if I can find one for a reasonable price.

Guy in my club put a new rear suspension on. I don't remember which one, but it eliminated the swing axle stuff. Took 6 seconds a lap off of Hallett.

A 1978 will have the 'swing spring'.
That will control rear camber and keep you from getting upside down.
You can follow the tried and true path for better handling:
1) lower and stiffer front coil springs.
2) stiffer front anti-roll bar.
3) Increase rear camber, to perhaps 1-2 degrees. Use a spacer block to get it down to 3-4 degrees, and then fit air shocks to allow you to 'tune' the rear camber. Near 0 for daily driving, more neg for auto-X.
4) Better shocks all around.
5) Alignment settings.

Voila, instant handling!

Yup ^^^^^^

And throw in some good brake pads.

That sounds better than I expected. I'll have to study the swing spring to understand how it works. I saw the diagram but was too sleepy to really get it. I replaced several springs while working at a dealership in 78 & 79 but never paid any attention to them. At the time I had no interest in Spitfires. I've never been crazy about the way they drive. They tend to shake a rattle worse than some of the other British sports cars IMO. I do know that they can make some really good race cars though. When I sold my MGB it was too stiff for road use but I drove it 10K in 10 years anyway. It did it's share of shaking and rattling too.

Where would be the best place to look for the front anti-roll bar and the rear air shocks? Also bushings. The stock ones look decent but I don't like the way it feels. I want to tighten it up a bit. It appears to have too much negative camber now. I an try the air shocks first and see where I am then.

I looked at Moss Motor's site for performance suspension parts and didn't see anything at all. I'll have to order their paper catalog.

It'll depend a bit on if you want to be competitive or just have fun. The rules haven't changed a whole lot since '93, but the cars in FSP have. Still... an old classic can do well - a current example being a particularly well driven early 70's BMW 2002. Hoosiers are still the way to go. Do you still want it to be a w/e street car?

For parts:

http://www.tsimportedautomotive.com/ (kinda crappy website, so you have to call him to get anything, but Ted is very knowledgeable about Spitfire race cars)

www.spitbits.com (better website; sells poly bushings and some other things)

Join the Yahoo North American Spitfire Squadron list/group. A couple of guys there have FSP cars. One of the guys has a website with a crap-ton of technical jargon: http://auskellian.com/paul/links_files/performance_enhancements.htm (if it sometimes reads like he's a rocket scientist - it's because he is)

All the above. GT6 stuff is a cheap/easy bolt on upgrade for brakes, springs, front sway bar etc. but don't do the Rotoflex rear suspension because it's a step backwards from the swing spring. SPAX adjustable shocks are nice but not cheap.

There's a place called PRI Race, the web site should be prirace.com but for some reason it's not coming up, they have all KINDS of Spitfire stuff. OBTW, they offer an 'IRS conversion' which, to my tired old eyes looks like a real halfway deal, as in no I wouldn't do it that way.

The car should already have a roll bar, unless you are looking for a thicker one. To me if you need air shocks, something else is wrong. Too much neg camber at the rear is a tired rear spring, but neg camber (some) is what you want for competition. I would go with Koni shocks instead of Spax, but all I've ever used is the standard old Woodhead shocks. You can get lowering springs pretty cheaply.

Spits really do shake rattle and roll. That comes more from its body of frame and not unit body construction.

spitfirebill wrote: The car should already have a roll bar, unless you are looking for a thicker one. To me if you need air shocks, something else is wrong. Too much neg camber at the rear is a tired rear spring, but neg camber (some) is what you want for competition. I would go with Koni shocks instead of Spax, but all I've ever used is the standard old Woodhead shocks. You can get lowering springs pretty cheaply. Spits really do shake rattle and roll. That comes more from its body of frame and not unit body construction.

Yes, you WILL need a thicker one (you said you WANT it to handle, right?)
The PROBLEM is that camber for good handling and camber for daily driving are two completely different values.
And the optimum camber for each of those may be different on any given day.
Best camber for handling depends on tires, the track, the temperature, etc.
Best camber for daily driving depends on what load you are carrying.
Air shocks enable you to quickly and easily ADJUST to whatever you want.
They are not a Band-Aid, they are a TOOL.

Curmudgeon wrote: ... There's a place called PRI Race, the web site should be prirace.com but for some reason it's not coming up, they have all KINDS of Spitfire stuff. ...

Be sure to bring the BIG wallet.
I'm not knocking PRI, there are some folks that really like it, and custom work for a niche market isn't cheap.

If you want to compete with the car, carefully check the rulebook before spending money.
I'm not aware of any competition Spitfire that uses the PRI stuff.
AFAIK, all the things I listed are legal mods in most organizations.

In reply to erohslc who said: Air shocks enable you to quickly and easily ADJUST to whatever you want. They are not a Band-Aid, they are a TOOL.

Yeah, that's the way I see it. I would think they might be the perfect solution for an S/P car.

I was working for BL back in those days too...

my one remaining sensation about squeezing into a Spitfire and driving them was the overwhelming sensation that if I hung my hand out the window... my knuckles would drag....

oldeskewltoy wrote: I was working for BL back in those days too... my one remaining sensation about squeezing into a Spitfire and driving them was the overwhelming sensation that if I hung my hand out the window... my knuckles would drag....

Wear driving gloves with little rollers mounted on the backside ;)

So are the air shocks adjusting camber by adjusting ride height?

nocones wrote: So are the air shocks adjusting camber by adjusting ride height?

Yep.

In reply to nocones:

The rear suspension is a swing-axle: fixed at the hubs & pivots at u-joints at the the differential which is bolted to the frame. Camber changes through suspension travel. Lower ride height = more negative.

Are you looking to do any engine mods?

There are some good ones that are relatively bolt on- like a euro dual SU intake and an LCB exhaust header. I know Vizard says a single flows better, but I know of people that swear by them.

You can delete the fan clutch assembly and add in an electric fan. Or wait- was that just on the Midgets?

Anyway, you are in the right place. The most limiting factor may be your pocket book...

Edit:

And another thing, here is a good guide to prepping a 1500 for performance:

http://www.spridgetguru.com/TA0012_1500.html

In reply to paranoid_android74:

I'll have to make a firm decision on which class before deciding about doing anything internal. The S/P rules used to say that you couldn't do anything internal. But was anything ever actually checked? IDK. Not that I'd want to cheat or anything though. Doesn't really matter that much anyway. I doubt I'd ever hinder a serious competitor from qualifying for the national Championships. I've had periods of success in the past but I know that everything physical that counts in autoX is slowing down. That's why I want to have one more shot at it. I know I'll still enjoy it. I think my autoX experience has saved my butt more than once during my lifetime.

Right on- I have no knowledge of those rules, so I don't know what's allowed.

The performance manual is worth a read though, as it also increases the life span of the engine. The weakest part of the 1500 engine is the bottom end. Readers digest version- enlarge the oil gallery on the center main as it tends to starve easily, baffle the oil sump for the same reason, bottom tap the main cap bolt holes and upgrade to grade 8 hardware, etc.

But you have to go though the hassle of pulling the engine and taking it apart. Not so fun if you are looking for plug-and-play auto crossing.

Just food for thought!