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N9T based Formula 2 engine?

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From the article on the history of the N9T motor: N9T history

A few years earlier, the ROC firm developed a high powered version of the Chrysler/Simca/Talbot OHC for Formula 2 racing. This engine had a 16 valve cylinder head and produced around 300hp at 8000rpm.

From the french forums, it sounds like this was quite the engine, and that ROC fitted/adapted a 16V head to the N9T block and used in F2/ Formula Alantic race cars. What would be cool - is to find out what that head was! F2 engines included the famous Ford BDA engines, so if the N9T based motor was built to play with those engines - that's a HUGE testament to how good they are.

I used to think the Danielson head was the holy grail - now I'm thinking this 16V head they used is! How cool would a 505 16 valve turbo would be! B)

Rabin

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I wonder what the deplacement was. Asuming it was a 2,2L N/A engine, 300 hp @ 8000rpm calculates to something like 120% VE B)

And I wonder what parts they used in the bottom-end...

16v 505 turbo would be totally awesome!

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It's definitely a 2L - no idea on specs.

Since I posted, I've found the following with the help of some friends:

http://membres.lycos.fr/rocauto/eindex.html

http://www.racecarsdirect.com/listing/2186...rts_2000cm.html

The ROC website clearly shows a picture and it does look like the Peugeot N9TE block... Now I just need to find out if the head is custom made, or if it is modified from another make. From the advert in the second link - I'm guessing it's a custom head and those are raw castings.

Cool history though!

Rabin

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Yep. That's Chrysler 2L engine block. Looks like at that head is un used and eaven not drilled.

V-M

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They did a prototype fuel injected 16valve Murena as well...in an attempt to make it competitive with the surge of gti cars that flooded the marked in the early 80's.

Power was supposedly in the 180'ies,which isn't bad for an early 80'ies 2.2 engine!! but the Murena range was supposedly killed off by Renault before it could be put into production.

s41.jpg

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Big question for me is what the origins of that head are for sure.

Was it based on a production head, and they sourced raw castings to modify? or was it all proprietary? I find it hard to believe they designed and built cast heads for such a small run of engines - but ya never know. Be so much cooler if it was based on a production unit.

That being said - even if it were a production unit, finding one, and then modifying the cam drive system and everything else necessary to fit it on an N9TE would likely be a show stopper.

I may be the only odd one here that's getting stoked about some really cool racing heritage these engines enjoyed that isn't widely known at all. VERY few engines are worthy to make it into Formula car racing - and the fact the same block was used to go against the legendary Cosworth BDA engines in F2 is pretty damn impressive.

Rabin

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Im pretty sure that none of the 16valve heads were based on actual production units.

And as for the dreams of finding one and getting it to work... I think it only has relevance if you are building an all out N/A race engine.

With a turbo it's no problem to flow plenty of air with the 8 valve layout.

I see why the roc heads might be appealing .. but if people want 16 valves.. I'd say.. get another engine. B)

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That has always been a dream of mine I to design my own cylinder head. I'm watching some real hopeful developments in the 3D printer space. Removing stereo lithography from the cost equasion leaves mold making and casting as the unknown expense items. I'd figure a cost of 2-3K.

The real cool thing is you could source the rocker and valves from a modern car!

Anybody know why the N9T uses a chain instead of a belt to drive the cam?

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Chain is much more reliable and longer lasting... Mercedes and BMW is gone back to chain is some engines.

V-M

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Chain is much more reliable and longer lasting... Mercedes and BMW is gone back to chain is some engines.

V-M

Perhaps longer lasting, but not more reliable. I've never heard of a belt going unless it's many miles past it's change-out perior. They it also rob power and are noisy. I've messed with both and actually prefer belts.

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Perhaps longer lasting, but not more reliable. I've never heard of a belt going unless it's many miles past it's change-out perior. They it also rob power and are noisy. I've messed with both and actually prefer belts.

Tell that to the Audi and VW owners of the 1.8T that had the timing belts snap well BEFORE the recommended change interval. :)

It also wasn't long ago that the Camry went back to chain drive as well - that should speak volumes.

While I don't mind belts, I certainly don't mind chain either. In a well designed system the losses are going to be minimal anyway. Having the security of a chain on an interferrence engine would also be somewhat re-assuring.

As an aside - when I was wrenching on the that RS200evo at Pikes Peak and the turbo let go, pieces of the turbo jammed the belt driven dry sump, and that in turn stopped the crank. Sadly - the timing belt that was running off the crank did not stop with the crank and the top end continued to rotate. $30K engine and a $10K turbo lost in less than a few minutes. Ouchy!

As for the 16V head - you're right about outright performance. But the coolness factor is off the chart with a purpose built 16V race head!

I'll be quite happy once I can get the Dani engine in and dialed in. Should give me plenty of giggles at 20 psi boost. B)

Rabin

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I think a possible resource would be to find an existing head that had the same cylinder spacing as the N9T, then modify it to fit.

The Ford 2.3 Turbo guys found a Volvo 16V head that can work, and the Turbo dodge guys figured they can use the Neon 16V heads on the old 2.5L bottom ends. I've heard of many other engine families that can swap heads with some work as well. (Suzuki comes to mind as well.)

LOTS of skills needed to make it work - but definitely possible if you can find the right head. (Chain drive cams and the right cylinder spacing would be critical I think.)

Rabin

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Perhaps longer lasting, but not more reliable. I've never heard of a belt going unless it's many miles past it's change-out perior. They it also rob power and are noisy. I've messed with both and actually prefer belts.

I prefer a chain, but most belt problems are because people don't change them when they should.

Ive heard many stories about them going 30,000 miles past their time.

Chysler 2.2/2.5s are one of the few I know of that wont bend their valves when they go, and some mechanics on those engines will tell you drive them until they break !

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This is the translated response I got from the Swiss seller of the ROC 16V castings:

hello I think in Canada you speak english like me in Switzerland.

Photo 874 and 875 and cylinder head covers CAMSHAFT special ROC

16 valves (manufacture ROC 200 copies)

Photo 876 and cylinder head covers CAMSHAFT ROC special 16-valve

imitation BMW F2 (making ROC 5 copies)

there is only the engine block from the series.

all else is special ROC

So definitely sounds like this was a custom casting designed and produced by ROC for the block. It's highly unlikely a complete ROC F2 engine will ever surface - but I'll always have it in the back of my mind just in case... :(

Rabin

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I found some old article on the ROC engine.

post-114-1233523514.jpg

Here's the source:

http://forums.autosport.com/printthread.php?threadid=93266

They're disscussing some chrysler/simca 2L JRD-engine, whatever that means.

Here is some info from the article:

4 cylinders

Displacement: 2000cc

Bore: 92mm

Stroke: 75mm

Compression ratio: 11,3:1

Power: 285 hp / 9200rpm

Torque: 36 mkg / 6200rpm (=353Nm) :(

4 valves/cylinder (Intake 37mm, exhaust 32mm), 2 ACI - triple ignition.

Fuel injection: Kugelfisher

That torque can't be right... it would mean 311hp/6200rpm and 176% VE :D

Also, VE at peak power with these numbers is now around 108%.

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Can anyone tell me the bore spacing of the Simca-Chrysler engine? I know something you don't about this head design...

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What you mean by bore spacing? Total length of block? Bores equally distance from each? Space between bores (depends 1,6-2L)?

V-M

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0.400 in picture is ~11,5mm with 92mm cylinder. So spacing is ~103,5mm.

V-M

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That was a random picture to explain it, it's probably less than 11.5mm on the Chrysler with 92mm bore.

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Eh... seems my english is so bad. I try to say... I measured it from actual block. 11,5mm is that wall thikness in 92mm bore. So its 103,5mm what you was asking.

V-M

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Interesting, the Chrysler engine is probably based on the BMW M10 engine layout but this one has a 100mm bore spacing. The design of the ROC 16v head is really, really close to the M10 based Schnitzer 20-4:

112470965.jpg

A really close head design was also used on the 6 cylinder version of the M10:

640px-BMW_Engine_M49_from_E9_CSL.JPG

Finally this 6 cylinder made his way on the Motorsport street cars (M1, M6, M5) and for the DTM aimed M3 E30 they chopped 2 cylinders and made the S14:

S14-car-engine-750x477.jpg

Unfortunatly with a 103.5mm bore spacing using the S14 head is probably too complicated.

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There :) Saab B204 and B234 engine head gasget fitted (basically same as 205/235), spacing looks okay.

post-43-0-73289700-1439915346_thumb.jpg

post-43-0-71790600-1439915365_thumb.jpg

post-43-0-49025200-1439915386_thumb.jpg

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