Zep
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520 ps is 512 bhp, metric horses aren't quite as manly. They must do some porting and cam work too to get that number if a 4.7 GTS makes 454 bhp (460 ps) at best. I'm intrigued as to the price
4.2 engine - internal mods?
- Thread starter m1980k
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520 ps is 512 bhp, metric horses aren't quite as manly. They must do some porting and cam work too to get that number if a 4.7 GTS makes 454 bhp (460 ps) at best. I'm intrigued as to the price
If they still offer the conversion I bet you wouldn't see change from about £25k, maybe more. Simply not worth it. Does their conversion include updated brakes? If not, add another £5k just to be sure!
I have to warn you, they are not cheap. And they do not reply on time. If you take a look at their web site, you'll find out prices and info.
I know a chap in Germany who has the bi-compressor 551 hp mod. If you are seriously interested, i can bring you in contact.
Sorry for the following question, but i can remember since your very first posts, that you were always looking at changing bits on your car. Are you sure that the GS is the right car for you? have you ever thought if you need something more fast and more track oriented?
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Hmmm, the more expensive it is, the more I have to think about it! I've requested a price list from Dimex/Leo Nardo.
I'm not looking for a stripped out track car. I know some people don't get why anyone would want to change a car. That's fine. But there are plenty of people on here with exhaust upgrades and remaps. People put the GS bodykit on a 42 or change the seats. Cars don't often come out of the factory in a perfect state. Some people want a bit more torque, some more top end power. Some want stiffer suspension, some softer. But the basic ingredients are there for these cars: wonderful V8 in a beautiful body.
A bit more bhp, better brakes, more precise handling, less (especially unsprung) weight - am I wrong to want those things?
From what i read, you want a lot more power and a lot-less weight.
The 4200 engine can either get 30 hp more or 150! There is no middle path.
I agree all of us have made some mods, including me, i just wanted to show you , after seven years of ownership that a 458 will always have 590 hp, handle a lot better and brake better than a GS, and maybe ask yourself deep inside, if you need something different to avoid all this period (time and money) changing something that maybe you won't be happy in the end.
In the meantime, have some whiskey, cause LeoNardo price will be high
The 4200 engine can either get 30 hp more or 150! There is no middle path.
I agree all of us have made some mods, including me, i just wanted to show you , after seven years of ownership that a 458 will always have 590 hp, handle a lot better and brake better than a GS, and maybe ask yourself deep inside, if you need something different to avoid all this period (time and money) changing something that maybe you won't be happy in the end.
In the meantime, have some whiskey, cause LeoNardo price will be high
Contigo
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Unless you go forced induction you won't see any really worthy gains. Best bang for buck is either a pulley or a blower.
GeoffCapes
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Was there not one on eBay a while back? Or was that a 4200?
Typically, there's a damaged facelift 4200 in my preferred colour combo for £12k right now. Bit soon for me as I'm still in the planning stage (and I really need to get a decent drive in the GS when temperatures rise above single digits before I think about my next car...)
http://www.ebay.co.uk/itm/like/2005...6824&clkid=3896844461027846114&_qi=RTM2065553
Gents, I too was toying with the 4.7 litre into a 4200 Coupe idea but I think it's a no no due to all the reasons you have mentioned, wet sump etc.
However, if the liners are the same size and it's just the crank stroke that gives you and extra 500 cc then it may be do-able.
I have been studying the supercharging option. I have built a supercharged Alfa using a Rotrex. The German Modena Sports twin Rotrex option is way too expensive at around £22k. There may be another way using the Jaguar / Range Rover supercharger from the 5 litre engines. ( its not the 4.2 litre Eaton unit ). I have such a supercharger and a spare 4.2 engine and I think it could work having offered up the charger to the engine. The main issues are moving the alternator and the oil accumulator under the plenumb chamber. ( not too difficult ) Of course, low compression pistons from JE pistons in the USA would be required, £1500 for eight. The water to air intercoolers and separate water pump from the Jag would have to be used. For the extra fuelling required a "pigging back" set of injectors would be needed. I would think that using an upgraded 'smaller' blower pully would mean around 530 BHP. If I can swing funds and the wife's permission I may start to rebuild my spare engine later this year. What do you think ?. john.
mjheathcote
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Regarding the extra 500cc, its a combination of increased bore size and stroke, not stroke alone unfortunately.
The Modena twin Rotex may be £22K, but on a DIY basis the component cost is nothing like that.
Think I would be looking at the same, or single Rotex, instead of removing the inlet manifold/alternator/oil accumulator.
The Modena twin Rotex may be £22K, but on a DIY basis the component cost is nothing like that.
Think I would be looking at the same, or single Rotex, instead of removing the inlet manifold/alternator/oil accumulator.
I think this is one of the most exciting posts I have read on this forum! I do not have the knowledge to create and build a supercharger conversion myself, but if somebody has the know-how and makes it work i will be a very willing student, or commissioner of a build for my GS.
I am now convinced that dropping in a 4.7 engine is not viable - too many unknowns with regards the electronics and they're all wet-sumped and so susceptible to variator failure. I wouldn't want to spend ££££ on a used engine and find a £4k problem lurking. Nobody yet seems to know for sure if the pistons and liners are the same for 4.2 and 4.7 engines - I suppose it would be easy enough to find out with a little investigation.
mjheathcote
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4.2 engine has a bore and stroke of 92mm x 79.8mm
4.7 engine has a bore and stroke of 94mm x 84.5mm
Thanks, Mike. I was told that the pistons, liners and crank should be able to fit the 4.2 block. I'm not sure it's worth the expense for a 40bhp increase and I'd be surprised if they come up for sale very often.
mjheathcote
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The liners might be the same size on the outside diameter, but of course slightly bigger bore for the 4.7 pistons.
Guess only one way to find out, have 2 engines to strip and play with.
SPX
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Unless you're simply after headline bhp figures, I'd be inclined to stay away from the engine initially.
If I was to start modding a Maserati I'd start with bigger brakes and forged wheels, if you get the set-up right then you can use the cars power for longer because you can brake later.
These were the Brabus brakes I had on mine (should have gone for lighter wheels but just love split rims!):
Cost was over £20k brand new and about £5k second hand, they were brutally sharp and made you feel sick when pressed hard.
If I was to start modding a Maserati I'd start with bigger brakes and forged wheels, if you get the set-up right then you can use the cars power for longer because you can brake later.
These were the Brabus brakes I had on mine (should have gone for lighter wheels but just love split rims!):
Cost was over £20k brand new and about £5k second hand, they were brutally sharp and made you feel sick when pressed hard.
alfatwo
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Unless you're simply after headline bhp figures, I'd be inclined to stay away from the engine initially.
If I was to start modding a Maserati I'd start with bigger brakes and forged wheels, if you get the set-up right then you can use the cars power for longer because you can brake later.
These were the Brabus brakes I had on mine (should have gone for lighter wheels but just love split rims!):
Cost was over £20k brand new and about £5k second hand, they were brutally sharp and made you feel sick when pressed hard.
That's the sort of stuff we need on our 3200,4200's .. as the standard Brembo's are far too small!
Dave
I'm starting to come around to this way of thinking - the weakness of these cars is not their engines!
I don't want to fundamentally change the character of the car, so superchargers (and 8 piston brakes) are out, but I think small tweaks in a lot of areas would add up to a lot. You could save between 50-80 kgs by changing the exhaust, brakes, wheels, battery, bonnet and seats (but I'm rather fond of those). Exhaust mods and remap can take power up to 440bhp. So you could increase power/weight by about 15% quite easily, with sharper handling and more stopping power.
I'm thinking about fitting the Formula Dynamics springs and anti-roll bars this year. The car came with brand new front discs and pads, so I might just go with stainless steel hoses and better pads until I replace the discs with larger ones. Might get the exhaust done next year.
Then, when you're talking 5,10 or 20k on superchargers or other engine mods, to me it makes more sense to go down the weight-saving route instead. Couldn't you get a carbon body for 20k?! Surely there are kilos and kilos of bolts and brackets etc. that could be replaced with titanium? Might not want to use plastic windows or anything like that (to preserve the car's GT capabilities), but a few lightweight panels might be good.
I reckon a c1500kg GS would be a lifetime keeper along the lines of this:
http://petrolicious.com/one-car-to-do-it-all-jack-olsen-s-911
BenjaminBraddock
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Or why not just enjoy the car as Maserati intended - it is a Maserati after all with 390HP and not a Ford Fiesta...