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I suspect I've been well and truly out-done, turning up in a Volvo estate is not going to cut it when the other visitors are turning up in V12 Ferrari's.
With regards to my engine there are a lot of unknowns - but that's why the heads have spent eight hours on a flow bench, and why the designer has both a full intake and a pair of tubular exhaust manifolds, so he can calculate exactly what cam profiles we need.
The camshafts in the 3.4 (which I have) are shared with the 2.5 - and if we kept them unchanged when we go to 3.7 litres then we'd be using camshafts that were designed to operate an engine almost a litre smaller in size, which would not be using the new capacity to its best advantage.
Unknowns currently concern the throttle body to use, I think that the exhaust side of things would be tubular (FVD style) tubular manifolds, 200 cell cats and the current Cargraphic sports exhaust. I'll need to check that we have enough injector to give us safe headroom, the goal is to achieve both a strong, linear delivery of power from idle and (in have your cake and eat it style) hit a volumetric efficiency figure of 100 bhp/litre.
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@NurseHolliday does your MX-5 have a coolant reroute? I've now got my Fast5 aluminium rad from Dan (thanks again) and pretty set on doing the reroute too. Won't be for a few months as spending £100-ish a month is my rule but think it's the right thing to do.
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Damn - that's a whole heap of complex experimentation you're taking on. Surely there must be a well established prescription for reliably bumping up the poke in those motors that doesn't require such a ground up design? All custom heads, cam and headers sound a bit Ker-F'ing'Ching, especially for a street motor.
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The 3.7 litre upgrade route has been extensively tested by Hartech, it's a development of their existing rebuild - the difference being 100mm diameter liners instead of the 96mm stock, and new pistons. They keep everything else the same as the rebuild, but that includes closing the deck as part of the rebuild due to the new liners.
What we're adding to that proven recipe is new cams, possibly some head work (although from stock the heads seem to flow exceptionally well) maybe a compression bump.
Port velocities on the stock head at stock capacity are actually very low for a modern engine - the increase in capacity both unshrouds the valves and increases pumping efficiency which brings the port velocities much closer to what we'd expect to see - but the cams are, as previously stated, a compromise for the 3.4, let alone the 3.7.
I don't think we're doing much that is totally new, hopefully what we're doing is, via testing and calculation, adding to and refining an existing recipe.
Fitting a Mezger might be cheaper, it is true - but I enjoy the project, the research, design, finding the parts etc. Also, it's fun to make the (very much unloved) M96 into the engine it might have been - an extension of the X51 program, if you will.
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This is cool stuff. What was the motivation? Just to get more contemporary performance or just because you can't help hot rodding? Both reasons equally valid.
I wanted to rebuild it to engineer out the weaknesses that Porsche left - the IMS, the bore ovality, the unsupported crank and associated RMS issues, the heating and oiling (under severe load).
Doing this involves (amongst other things) the new cylinders - at which point it's the cost of new pistons to get the capacity increase.
But - the issue with upping capacity and changing nothing else is that whilst you move the entire power band up you also move it left, so peak power rises to (say) 340 bhp, but it also moves to 6,000 rpm rather than 6,500.
I started thinking about what we could do to keep the engine revving out to it's previous peak, which lead to the discussion with the engine designer, his flow bench, new cam profiles being created and so forth.
I'm also going to use the oiling and cooling upgrades from the X51 Power Kit, including the new sump, scavenge pumps, and additional centre radiator.
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All makes total sense and will be a unique cab for sure. Good thing it's being done properly and taking oiling into account. So many engines blow because novice builders ignore it.
When you get to exhaust make sure you plan to swap a few things around and try different combinations. Last thing you want is a good note at high rpm but droning or booming on light throttle or cruise.
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Ever wondered what it costs to look after an F1?
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Looks like it might be the same one: http://uk.businessinsider.com/pebble-beach-mclaren-f1-lm-auction-sothebys-2015-8
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I don’t have a coolant reroute. It’s supposedly only needed for forced induction, and I didn’t have one on the supercharged car, so who knows?
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Yeah, you need both back seats down, then both wheels off (any decent sized mtb/ enduro!) and they will stack up with plenty of space for about 5 days travel.
Take two blankets / old carpet, one for under the bikes to flop over bit of back seat fabric (derailleur will sit on it) and another between them. Managed for years like that before getting a diesel powered Iso container -
Car ownership has been postponed. 'Full service history' meant 'no history at all'. 'Nice and clean' meant ashes in the ashtrays, sticky seats and seatbelts that didn't retract. 'Power steering' meant 'No power steering' etc. As my 9 yo put it during the test drive: 'This is shit - I really don't think we should buy it'...
The sellers profile suggested it was a female pensioner selling - reality was a guy who just 'sold it for a mate who had a used car dealership'. So he was basically just trying to shift shit stock, without having to give a warranty...
Dammit
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Car appreciation... the aesthetics, the engineering, etc
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^ Is like a 1:1 toyshop homage.