Quite the pair in the shop 78 308 and Merak

Such a rare occasion that both a late Merak SS and 78 308 GTS are in the shop let alone that both are in with engines out. Merak (euro bumpers) with a blown head gasket (overheating), 308 blown head gasket (overheating). I swear you can’t make this stuff up.

The extremely stuck 308 head only took 4 days to removed. Minimal violence involved, no animals were harmed, no whacky head puller either. Just lots of patience, soaking of head studs, and heat cycling up to 250F+ over the course of a few days. The bottom end is in fabulous shape so this is just a top end job for another fchatter.

Merak actually arrived here in a million pieces. Someone took it apart, cleaned it up and gave up. Thankfully nothing was mucked up. Absolutely the nicest Merak I’ve ever seen though with a 1 of 1 factory two tone paint job in this combo. 17k original documented miles. The crank showed borderline rod journals so I offset ground the crank with Marine crankshaft, different rods, different pistons and presto we have a 3.3L stroked Merak. Just waiting for the new longer duration and higher lift camshafts to compliment its higher compression and it’s good to go. Maserati was actually a bit more honest about their bhp rating in this era.



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Gents, note the really good old Elring head gaskets are NLA. The new Elring head gaskets are similar but aside from being far more pricey are not what they used to be. Sangalli use Victor Reinz head gasket material, which is good, but Bill at GT car parts hit the nail on the head by adding piping like the old Elring gaskets. I believe Cometic can crank out a fiber gasket using the same Victor Reinz material Sangalli use, but no piping. In the absence of piping I recommend using Permatex Aviation Sealant.

I really like these old Citroen SM/Merak engines. Wider than they are long. Lots of racing success in their day in the Ligier JS2. A freaky rare 4v version was made as well, which I am trying to acquire. Maybe a dozen made. Will keep all posted on that ;D

 

As JCR linked, Marine Crankshaft is just a crankshaft shop in CA. They hands down do the best crank work around. I had them take the rod journals offset down to 50mm as I found the BMW N55 rod fits the application perfectly at that diameter. I snapped up a set of Manley rods (lighter and stronger) and specified the pin location on the new pistons and had Marine balance it all after offset grinding and nitriding. Had to remove quite a bit of weight on the crank due to the lighter components, which is a good thing. The SM/Merak crank is a bit of a boat anchor so removing material from the rod throws is a no-brainer.

This cannot be done with a 308 crank as the rod journals are already pretty small at 47mm. Use a 360 crank

 

Interesting to note is the weight difference of these two units. The Merak drivetrain is together. Total weight of the Maser engine/gearbox is 452lbs while the 308 engine is 608lbs. 308 of course makes up for it with a solid 20bhp more on tap, but over 150lbs weight difference is really something considering they're both otherwise just 3L quad cam Italian units.

 

Update on the 308. Engine is tight again with under 4% leak across the board now. The 5-8 bank had a blown head gasket and the leakdown test showed cylinder 6 was blowing into cylinder 7. Should be together and back in the car shortly.

New front to back stainless system going in as well.
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I agree it's a super weird engine and I completely understand why someone just threw their hands up with this thing and left in in pieces. Sort of like that early 60s odd fire Buick engine later used in Jeeps too, what was it called? Hellfire? Somethin. Anyway, Maser made this engine to be wider than it is long specifically for Citroen's mounting requirements in the SM. The jackshaft driving the chains was also a funky requirement to drive the hydraulic system and ancillaries. I can't be entirely mad at that design as all the ancillaries are so easy to get to. This engine though, in both 2v and 4v variants, has a great racing history in the Ligier JS2, including winning its class at Lemans and 8th overall besting a number of Daytona's and RSRs, and won the tour de France, so I wouldn't say it's a total disaster, just weird as hell. The combustion chamber design of the 4v racing version of this engine, which competed against the Cosworth DFV in sports cars, was also Alfieri's basis for the Countach 4v downdraft while at Lamborghini some years later.

I did not know you offset ground your 3.5L 328, I thought you used a 360 crank. Good to know. Those Honda racing bearings can handle some serious Yakuza level abuse.

 

LOL. Love it. No doubt some head-scratching designs there, I just haven't experienced any Titanic levels of failure with them I guess. I've only done a few now but I'm sure in-period was when stuff hit the fan as so many had no idea how to work on them, which is absolutely the fault of many European brands in the US, lack of mechanics who had a clue what to do. Just like why 90% of the carbureted 308s that come in here are never running right. The early chain tensioner design was a known issue hence why it was changed to the Maserati V8 tensioner design but with an arm and sprocket, never heard of one of those failing. As for the cam nuts, whoever tightened them clearly didn't do it right or use the factory tool as so many over the years used a chisel to both loosen and tighten the nuts, which would absolutely cause failure. I've never heard of one which was worked on by a shop that knew what they were doing with them go loose. RIP Jerry Hathaway who set the 3L land speed record at over 200mph at Bonneville with one.

I just know compared to the NART 308GT4 entry at 73 Lemans, the JS2 qualified 30 seconds ahead and won its category and punched well above it's weight while the 308 never could finish Lemans. 308 was just not a good race engine, not reliable.

I love both for different reasons though. 308 is a better road engine and far stronger gearbox but definitely requires more 3-5yr maintenance as opposed to a properly setup late Merak engine which doesn't need any of that nonsense. Bosch ignition, no timing belts every 3-5yrs, better water pump design, it's far lighter, and not nearly as many shaft seals to leak. That said, why on Earth did Maser approve just 210-220bhp for this thing? Just absurd considering its application.

 

Tension mechanism beginning around 75
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Thanks, thankfully I caught it that day. Forgot the flywheel turned clockwise (when looking at the flywheel directly)

I was always told the early tensioners were the ones failing, hence the change to the arm style. Note the insides of the 75-forward tensioner has a spring-loaded and oil fed detent mechanism, so it's not an oil-fed mechanism, it's sprung so when the chain stretches enough the spring pushes the inside mechanism forward another notch and it locks in place. Same one used on the V8 engine, only on the V8 engines the pad actuates directly against the chain. Never head of one of them failing but who knows.

 

Back to ferrari normalcy. Nouvalari exhaust arrived for this thing. They really do some nice work. Headers look fabulous. The bends, albeit not completely mandrel bent (many are though), are a good bit cleaner than stock manifolds. Definitely a bit of power in these things even if it’s just a little
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And she’s back in. There’s exactly one way these like to go in and out. Fit and finish of the new exhaust components is sublime. Highly recommended.
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