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Starglider Wrote:stunned_monkey Wrote:JZD was trying to buy the Renault 2.5 turbo. The car could have had the same powerplant as wne into the GTA
Maybe, but this car comes from a timeline where Legend stayed on board, at least for the twin turbo. Although we have to assume alternate universe Martin G got hold of it in the early 2000s and replaced the K-Jet with EFI
No way he wouldn't have switched to the Renault engine IMO, otherwise he was paying to develop something independently of the manufacturer of the engine... wouldn't have made business sense.
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stunned_monkey Wrote:No way he wouldn't have switched to the Renault engine IMO, otherwise he was paying to develop something independently of the manufacturer of the engine... wouldn't have made business sense.
The GTA Turbo didn't appear in the US until 1987 and only made 177 HP (in US emissions spec). Legend would have been ready by 1983 and the TT would have been at least 240 HP. So while I can see the Renault 2.5 turbo powering a single-turbo DMC-12, an option which was always going to be introduced later than the twin, I can't see it replacing the TT as the top end model. Of course, you may know something critical about Renault engine development I don't.
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While I haven't actually *seen* the correspondance between JZD and Renault, I have had much of it read to me down the phone! JD was trying his best to convince them to let him have engines without actually paying for them up front. There was also talk about branding the GTA turbo as DMC in the US.
The GTA was never available in the US but the D502 models would have been suitable from 1987 onwards as you say. The engine was designed to support the lambda system and other than the cat, the lambda sensor pin on the ECU being wired up and fractionally lower compression pistons being fitted (which has as much to do with fuel quality as it does emissions) there were no changes.
As for single versus twin turbo - there's no reason why twins couldn't be fitted in place of the native single - it just requires a bespoke exhaust, extra oil plumbing (the drain being the bigger challenge - supply is easy. FWIW the standard single turbo config doesn't fit in the DeLorean engine bay by about half an inch, and gets very hot.
From a technical point of view, I'd be interested to learn when the Renault engineers elected to bin odd-fire and move to even. *probably* due to limitations to the early EFI they planned on using, but they never revisited it, even going as far as addiing a counter rotating balance shaft on euro 3 litres. Going back to odd-fire would have fixed the balance issue.
So why would DMC have abandoned Legend? If the manufacturer of the engine is already designing a turbo version which you will be able to buy outright, why would you instead buy an older design and out-source its conversion or bespoke parts sourcing (and getting into the engine-building game at the same time)?
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stunned_monkey Wrote:So why would DMC have abandoned Legend? If the manufacturer of the engine is already designing a turbo version which you will be able to buy outright, why would you instead buy an older design and out-source its conversion or bespoke parts sourcing (and getting into the engine-building game at the same time)?
Because all of the 80s Alpines were under 10 psi of boost and didn't even meet JZD's original 200hp power goal? AFAIK Alpine didn't get up to Legend levels of boost and power until the later A610s, in the mid 90s. I assume Alpine wouldn't just leave power on the table, so Legend must have been doing something (custom pistons and heads?) that wasn't available from Renault or viable as a custom on Alpine volumes. Legend development would have been a sunk cost by the time any Renault turbo became available, and the PR build-up was already in progress for it. Given the DMC-12s reputation at the time, I think JZD would've wanted the fastest possible car ASAP to challenge the 'slow DeLorean' perception, even if it ended up a low-volume range topper vs a more profitable single turbo.
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The gta runs 10psi where it pushes 200hp before emissions controls as standard but is mapped to 1 bar. The legend prototypes are all non cat equipped I believe. Also hp figures are only part of the story as they're extremely torquey. An a610 will trounce a v6 clio 255 for example
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stunned_monkey Wrote:The gta runs 10psi where it pushes 200hp before emissions controls as standard but is mapped to 1 bar. The legend prototypes are all non cat equipped I believe.
I've seen 320hp quoted for a Legend prototype on bench, although that was most likely with more boost than could be made reliable in production.
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I think Marc Levy once told me it was running over 20psi boost - could've imagined it though.
Renault saw fit to increase the oil pump throughput and to cross-bolt the two middle bearing caps on the later engines. They also redesigned the liners and seats, presumably due to failures in the marketplace (Renault 25 as well). Steve Wiggins' #3352 which I finished last year has one of these late generation engines - 100% original internally. Hopefully one day he'll get bored of 200hp and let me play with it some more
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Found these badges, will put one on the engine cover and one in the engine bay;
Might slightly reduce the number of 'what engine does it have' questions.
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Starglider Wrote:Found these badges, will put one on the engine cover and one in the engine bay;
Might slightly reduce the number of 'what engine does it have' questions.
you hope!!
The question I get is "who's engine is it then?"
I often reply - mine, I bought it with the car
I'm getting far too sarcastic and less tolerant of the great unwashed the older I get........
Claire Wright - Club Treasurer
Jul 1981 DeLorean - Flopsy #2292
Aug 1989 Cavalier 1.6L - Guinney
Apr 2021 Mokka-e Launch Edition - Evie
#170
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Guinney1971 Wrote:The question I get is "who's engine is it then?"
I often reply - mine, I bought it with the car
HA-HA-HA-HA-HA!!!!!!!! :lol:
Rissy
(Forum Member 288)
(DOC Member 663)
May 1981 vin#1458 "LEX"
Grey, Flapped, Black
Chassis: #1073
Engine: #2839
Main Car(s):
2005 BMW M3 in Velvet Blue
2010 Honda Civic Type R in Sapphire Blue (1 of 115 made)
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Windscreen fitted, car is coming along;
VIN plate;
Didn't have original horns so fitted a pair of new Bosch units. They sound good but draw about twice the current of the originals, so spliced in a horn relay along with John Hervey's lighting circuit relay (to prevent arcing destroying the switches);
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Horn relay is a great idea, even the standard two horns draw a lot of current. On mine, either horn works great independantly and there is 12.4V at each, but if both are connected at once you only get a faint 'pheep'. I think that's lack of current.
Was the middle of your boot floor cut out?
Richard Hanlon
Derbyshire
DOC 393
1981 DMC-12 VIN 06126
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Rich Hanlon Wrote:On mine, either horn works great independantly and there is 12.4V at each, but if both are connected at once you only get a faint 'pheep'. I think that's lack of current.
That's probably a bad connection somewhere. The horn switch itself doesn't have a significant resistance, I just didn't want it eventually spot-welding itself the way the main lighting switch often does (in the original non-relay running lights design).
Quote:Was the middle of your boot floor cut out?
No, there was no boot floor in the pile of recovered parts. Chris made one but it isn't currently fitted.
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Just purchased this new vehicle to complement the DeLorean (e.g. tow it when it breaks down ). It has a film history only slightly less illustrious than the BTTF trilogy - and there are even less of them in the UK than there are DeLoreans! This one is converted to LPG to tame the fuel consumption, it's a fun drive but definitely needs some dynamatting. Also the previous owner had some funny ideas about suspension height which I will adjust.
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