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Ian F
Ian F UltimaDork
10/23/13 1:27 p.m.

In reply to tuna55:

That's one of the reasons for going with a Miata front subframe - the space-hogging upper control arms go away so there will be a bit more room for things like exhaust manifolds. Unfortunately, there are other pitfalls that make the Miata subframes harder in the 1800 than in the MGB... but NOHOME will find them eventually. I just hope the car isn't beyond saving when he does, or he can find solutions where I wasn't able to.

JoeyM wrote: He's a GRMer....stock firewalls are more a suggestion as to engine placement than a mandatory requirement.

If he were building a race car, I'd agree with you. But a car for his wife to drive? Adding in that criteria adds a level of complexity to the build far beyond simply making an engine fit.

Seriously... see if she can get a ride (or drive) a Cobra around... as that's basically what the car will end up like from an ergonomic point of view. Only with less ventilation since it's not a convertible.

tuna55
tuna55 PowerDork
10/23/13 1:38 p.m.
Ian F wrote: In reply to tuna55: That's one of the reasons for going with a Miata front subframe - the space-hogging upper control arms go away so there will be a bit more room for things like exhaust manifolds. Unfortunately, there are other pitfalls that make the Miata subframes harder in the 1800 than in the MGB... but NOHOME will find them eventually. I just hope the car isn't beyond saving when he does, or he can find solutions where I wasn't able to.

Wait, the Miata doesn't have upper control arms? I don't understand. I agree on the room, though, the V type thing doesn't fit well, it's too narrow, the inner fenders were too well integrated into the car to move, the frame rails were in the way, the master cylinder was in the way, etc. We could get it in there, but working on it would be a super challenge.

Keith Tanner
Keith Tanner MegaDork
10/23/13 1:47 p.m.

Nice! I'm not gonna apologize at all though. I love the 1800ES.

I wouldn't try to fit the Miata subframe. I built my own front end using the Miata pickups. It's about the same amount of work, but you'll get more space and save weight. Then you can move the inner fenders around.

The Miata does indeed have upper control arms. But they may be more compact than the Volvo ones.

What's the stock front track on one of these? Will the Miata track fit under those fenders?

NOHOME
NOHOME Dork
10/23/13 2:10 p.m.
Keith Tanner wrote: Nice! I'm not gonna apologize at all though. I love the 1800ES. I wouldn't try to fit the Miata subframe. I built my own front end using the Miata pickups. It's about the same amount of work, but you'll get more space and save weight. Then you can move the inner fenders around. What's the stock front track on one of these? Will the Miata track fit under those fenders?

Keith...

Keep in mind that I have yet to slide the sub-frame under the front chassis rails of the Volvo. A lot of things will begin to happen once physical realities collide with my ability to engineer solutions. It's not like I am expecting this to bolt on. The tool arsenal is well stocked for any eventuality.

I am aware of your solution with the MGB GT. Certainly not rejected out of hand.

A interesting approach that might come into play if it makes sense is where the entire Miata substructure is grafted under the Volvo shell. There is a good example of this on the Miata V8 forum using a Saab shell.

No one says I have to keep any of the Volvo from the nose forward; I can do a tube frame front clip. While I hate to waste the perfect chassis rails on the tub, If they gotta go and get replaced with something else, then so be it.

And to all the Volvo lovers out there, ....yup...there is a possibility that this will go all wrong either in the results or on the way. Avoiding that is what makes this fun!

I also agree that firewalls are not trivial. Heat, noise and safety all need to be considered. I already have an MGB GT that feels like across between an oven and a small airplane when traveling; the heat and noise are exhausting (bad pun there).

Ian F
Ian F UltimaDork
10/23/13 3:00 p.m.

Grafting the Volvo body onto a Miata pan is actually something I had considered as well and possibly the best way to approach this.

The track and wheelbase very close. The NA track is a bit wider, but there's a lot of "wheel tuck" on an 1800 so as long as you don't go nuts with wide wheels, it should be pretty close. The wheelbases are close enough that you may be able to shift the front and rear openings without it looking weird.

Where are you located (update your profile! )? I would definitely interested in any ofhte Volvo parts mechanical or sheet metal you don't need.

I don't really mean to be discouraging... it's just that guys have been trying to stuff V8's into these car for almost 50 years (pretty much since they were new) and while there have been a number of completed cars, none have been done well (heat? foot room?). This is a path heavily travelled and littered with failed hulks.

alfadriver
alfadriver PowerDork
10/23/13 3:04 p.m.

In reply to NOHOME:

Just out of curiosity, are you thinking of using the separate front and rear sub-frames, or the entire rollerskate frame?

I've "dreamt" about both for an alfa- including stretching the driveshaft and mid-frame for the GTV or Berlina- (both of which have longer WB's than the Miata).

for my application- there's already a cross member that holds the suspension- it would appear to be straight forward to cut that out, and replace it with the Miata equivallent. The big worry being it's relation to the wheels. Should be clear i've not done any measuring, yet.

I very much look forward to this build.

tuna55
tuna55 PowerDork
10/23/13 3:07 p.m.

Good call Alfa, using the whole backbone thing might help out with locating some parts.

Nohome, don't let us discourage you, we're just bench racing for you. I hope we're helping!

volvoclearinghouse
volvoclearinghouse HalfDork
10/23/13 3:30 p.m.

I actually measured the wheelbase of a mIata and compared it to a 122 (close to an 1800); the Miata WB is something like 85". The 122 wheelbase is about 100. Having parked an 1800 next to a 122, I think their WB are almost identical. So that's a 15" difference. That's kindof a lot.

I've thought about a 2.3 Duratec in a 122/ 1800 frame. That would give you pretty decent power and good fuel economy, too. The 302 is a pretty narrow V8, but it's still a Vee-freaking-eight.

Or turbo the volvo B20. Those engines have stupid tough bottom ends, blocks, and heads. I saw one on youtube pushing 400HP. Of course if you're stuck on an automatic trans, beefing up the mediocre BW35 might be tough. Adapt a Turbo 350? ;-)

Keith Tanner
Keith Tanner MegaDork
10/23/13 3:34 p.m.

The only thing you get out of the entire rollerskate vs front and rear subframes is mounts for the trans and diff. FYI.

NOHOME
NOHOME Dork
10/23/13 5:04 p.m.
volvoclearinghouse wrote: I actually measured the wheelbase of a mIata and compared it to a 122 (close to an 1800); the Miata WB is something like 85". The 122 wheelbase is about 100. Having parked an 1800 next to a 122, I think their WB are almost identical. So that's a 15" difference. That's kindof a lot. I've thought about a 2.3 Duratec in a 122/ 1800 frame. That would give you pretty decent power and good fuel economy, too. The 302 is a pretty narrow V8, but it's still a Vee-freaking-eight. Or turbo the volvo B20. Those engines have stupid tough bottom ends, blocks, and heads. I saw one on youtube pushing 400HP. Of course if you're stuck on an automatic trans, beefing up the mediocre BW35 might be tough. Adapt a Turbo 350? ;-)

Volvo wheelbase 96.5" Miata wheelbase 89.2"....so 7.3" difference. I'll chance it.

Volvo track 51.6" Miata: front track 55.5" in...rear track 56.2 in so roughly 2"/side I have to absorb under the fenders. Not trivial, but the wheels on the Volvo are way tucked in.

The Volvo list width as 66.9" and the Miata is actually narrower at 65.9, so while this does not really mean much due to fender shapes or knowing where it was measured, it offers hope that we can get under the fenders with Miata wheels.

No need worry about offending me unintentionally or otherwise! I know how far out on the limb I am standing. I also know that if it all goes wrong I won't have lost anything, but gained more experience. I do feel for anybody watching this who could use a rust free shell to kick start their project, but then again this one was for sale for a long time and nobody was interested, so it must not have much value.

Keith Tanner
Keith Tanner MegaDork
10/23/13 5:06 p.m.

Let me know if you need any dimensions off the Miata, such as the distance face to face on wheels. Your offset will have an effect here, of course.

NOHOME
NOHOME UltraDork
10/23/13 9:08 p.m.

Well guys, the good news is the bad news!

Everywhere that the Miata sub-frame needs to be, there just happens to be Volvo using up that piece of 3D reality. I have work to do.

Here is the money shot:

The numbers on the frame are outside dimensions of the frame rail. The upshot is about 100% interference between the Volvo frame rails and the Miata sub-frame.

Not a big deal, but it demands a decision to move forward; Do I edit the Volvo frame rail from the firewall forward to fit the sub-frame contours, or do I decide that I will ditch the Miata sub-frame and do a combination of sub-frame mods and pick-up points for the Miata a-arms? Or...do I go looking for a scrap Miata to carve a front clip? I am starting to like option 3..any of you canuks got a lead to a dead miata that wants to be reborn?

On another subject, I gotta admit that I feel like I am about to stab the last unicorn! This shell is so rust free that it just feels wrong to be defiling it! I looked at a few Volvos during the hunt, and pretty much every one had rust in the frame-rails where they kick up into the firewall. This thing is not only rust free, but some nice person paid to have all the nasty crud removed!

You gotta love the foreplay part of a project just before the first cut!

tuna55
tuna55 PowerDork
10/23/13 9:37 p.m.

In reply to NOHOME:

If it were me, I would stick to the Volvo front suspension. You could spend the same amount of time tweaking the existing geometry, fabricating new control arms, sourcing new knuckles, whatever, and you would be time ahead of making this Miata front suspension fit. Not only that, but I bet it would handle better as well. We love the Miata for a lot of reasons, but it isn't magic. If anything, I would look at swapping the rear suspension instead.

My opinion only, we're watching with bated breath for updates and I love your detail, as compared to my hack n' slash.

Ian F
Ian F UltimaDork
10/23/13 9:44 p.m.

Yes... I will likely shed a tear after seeing the first irreversible cutting picture... that car is so clean compared to mine... I'd give a lot to have that shell... it would save me so much work. I basically look at the Wolf Steel website and go, "yep... give me one of everything..." and I'll still be fabricating a lot of sections from scratch since patch panels aren't available.

I never saw it for sale... but it depends on where it was advertised... CL is not the place to sell something like this... it should have been posted on the 1800List and I have no recollection of seeing it posted there. But again, the issue is: "Where is it???" If it's hundreds of miles away, there's simply no practical way to get it to PA.

Keith Tanner
Keith Tanner MegaDork
10/24/13 6:53 a.m.
tuna55 wrote: In reply to NOHOME: If it were me, I would stick to the Volvo front suspension. You could spend the same amount of time tweaking the existing geometry, fabricating new control arms, sourcing new knuckles, whatever, and you would be time ahead of making this Miata front suspension fit. Not only that, but I bet it would handle better as well. We love the Miata for a lot of reasons, but it isn't magic. If anything, I would look at swapping the rear suspension instead.

Actually, the Miata suspension is quite good from a geometry point of view. Roll center control in particular is very well done. If you're going to pick a small car for a suspension donor, it's an excellent one to use - especially since you have a good selection of upgrades when you're done.

NOHOME
NOHOME Dork
10/24/13 7:15 a.m.

So, pondering right along!

I need to nail something down here to make any progress, and I suspect that without giving away any trade secrets Keith and or Warren can point me in the "right" or "wrong " direction by either confirming or negating my assumptions. Ian, the Volvo one is up to you.

The two pictures show some assumptions that I would like to be correct.

alfadriver
alfadriver PowerDork
10/24/13 7:18 a.m.

How much of the subframe can you knock out before it changes the pick up points?

It's pretty clear that something has to budge on the car, but hey....

Remeber, Andy took a really solid and very rare Fiat 1200 and made that into a Challenge car with a V8. It's just a car. And if you do a good job, and it gets a lot of driving time, IMHO, it's worth it.

Perhaps I need to give my buddy a call who has a Giulia TI. I'm pretty sure I can source the Miata sub frames. Make a great car to leave in Puerto Rico.

Where Alfisti will really hate me- I would also change the powertrain. Just like you.

If it helps- I know of a V8 GTV that was done in Canada- totally cut up a great car for a V8. And I know of a second GTV where it was "converted" to an S2000 engine- lots of cutting there. And a third that has some Nissan engine installed.

While I really respect the P1800, GTV's are considered quite a bit more valuable.

Go for it.

alfadriver
alfadriver PowerDork
10/24/13 7:21 a.m.

In reply to NOHOME:

To your pondering right along.

Where that top part of the subframe is- where you indicate the axle centerline.

How high is that off the ground in a proper ride height Miata? (or even slightly lower)

Correspondingly- how high is the same point on the Volvo?

Which is to reall ask- if the subframe COULD rest there, is that the right height, or would that have to move?

volvoclearinghouse
volvoclearinghouse HalfDork
10/24/13 7:42 a.m.

The Miata front end would give you rack &/or pinion steering, which should be a big improvement over the stock Volvo steering box. That would be the main improvement in my eyes. If you could maintain the stock Volvo suspension and adapt the rack/ pinion setup that might be a good compromise.

The indie rear would be more worth fighting for. But then, if you have stock Volvo up front and Miata in rear, you'll have two very different bolt patterns. There are ways to rectify that, however.

I've parted out a few very rusty ES's. Even those rusty shells it pained me to scrap, because the ES is somewhat rare. But they were beyond any reasonable restoration. I hate to be this guy, but if I were planning a project that involved significant altering of the car shell/ frame/ unibody, for a car this rare, I'd pick a less pristine example to start with. ES values have been going up lately, I'm surprised this shell didn't find any takers.

Keith Tanner
Keith Tanner MegaDork
10/24/13 9:23 a.m.

If someone wants to save the shell, they should have bought it. The fact that this one is pristine (well, as pristine as a bare shell can be considered, it's not exactly a concours winner right now) only makes it a better example to start with. Rust repair sucks.

I'll see what I can determine on those subframe pickup details. Honestly, it's not something I check often - the angle of the subframe is determined by the car, and that was Mazda's job I'm 95% sure it's level, though.

NOHOME
NOHOME Dork
10/24/13 12:48 p.m.

Thanks Keith...

I have fished around the internet asking this question before, and the consensus is that is sure seems to be flat. If it is not perfectly so. Anti-dive and caster are kinda at stake here.

If I can use the upper mounting pad to establish a plane relative to my surface plate, and establish an x-y relationship with the Volvo using the centerline holes I have a good footing to start from. From that point, my measurements can be relevant to decision and design needs and not just eye-ball observations.

As to Alfadriver's question, I don't know yet, but assuming a 205-50-15 size tire, I can set the height of the sub-rame with the lower a-arm parallel to the ground and measure. I was never intending to use the top as an attachment point, I only need to verify that the hole gives me a datum point representative of the front axle centerline.

I have been looking at the Exocet and can't help but want to cut the front clip off of that and graft it on to the front of the Volvo's firewall. Do you want to sell me some tubes Warren?

As to the shell being too good to cut up Keith got that right!

"Rust repair sucks."

I agree, and I happen to be someone who does a LOT of it as a hobby.

Ian F
Ian F UltimaDork
10/24/13 2:23 p.m.
Keith Tanner wrote: If someone wants to save the shell, they should have bought it. The fact that this one is pristine (well, as pristine as a bare shell can be considered, it's not exactly a concours winner right now) only makes it a better example to start with. Rust repair sucks.

The problem is he (and the car's previous owner) are in Canada and it appears to have been poorly advertised for finding a buyer.

If I'm being honest, that's a $2000 shell in the States. Easily. But the market seems to be different up there.

Keith Tanner
Keith Tanner MegaDork
10/24/13 2:32 p.m.

That's not a problem, it's an opportunity for nohome.

JoeyM
JoeyM Mod Squad
10/24/13 2:49 p.m.
Ian F wrote: The problem is he (and the car's previous owner) are in Canada and it appears to have been poorly advertised for finding a buyer.

I seem to remember a certain zamboni being a really great deal because it was poorly advertised (i.e. typo in the name.)

Sine_Qua_Non
Sine_Qua_Non Reader
10/24/13 3:32 p.m.
Ian F wrote:
Keith Tanner wrote: If someone wants to save the shell, they should have bought it. The fact that this one is pristine (well, as pristine as a bare shell can be considered, it's not exactly a concours winner right now) only makes it a better example to start with. Rust repair sucks.
The problem is he (and the car's previous owner) are in Canada and it appears to have been poorly advertised for finding a buyer. If I'm being honest, that's a $2000 shell in the States. Easily. But the market seems to be different up there.

Regardless, cars from Canada is usually notoriously rusty. Seems strange that it is rust free to begin with.

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