silverboy

Due to living outside of the US, I decided to proceed with a 4.05L kit from the Capricorn Group. They supply liners, pistons/rings...etc to ALL of the F1 teams except Toro Rosso and Ferrari so their credentials look EXTREMELY respectable. Cargraphic and Manthey also use them.

Anyway, I dont want to lose the dynamism of the Metzer engine in terms of revs and was pleased to find out that the weight of their pistons/rings weigh only 440gms which is less than the stock weights over 500gms.

All machining will be done in Germany. I'm getting new OEM bores from them too for them to work on.

Can't wait.

Peter

CRex

Ooo exciting... I assume you have one heck of a good mechanic to take care of you locally? Pls post a link to this 4.05 kit!

BBMGT3

silverboy, I am extremely interesting to hear your feedback on this kit. I also live outside the US and my only option at the moment is to somehow ship my engine to one of the rebuilders. But you'd need a DAMN good mechanic and some kind of software support to retune all the electronics etc...

silverboy

Yes an Brit with extensive race experience and is based in Singapore.

http://www.capricorngroup.net/no_cache/en.html

silverboy

Yes as mentioned to Crex I have a British mechanic who has extensive race experience. Will also do a custom tune to suit local conditions. Cheers.

P.J.S.

Subscribed
Awesome

Erik

Sbuscribed. I presume they are changing the crankshaft too ?

sharkster

be careful on that set up mate... seriously the hardware is heavier and different than the slightly smaller 3.9 bore. The temps will also change and there's very little margin for error with the machine work (also you can't go back to stock afterwards). Obviously best of luck though!

Carrera GT

I think you've asked the crucial question: Will this 4.05l have the same or better character than the Mezger in stock 3.8 or factory 3.9? For all the cost, complexity, question marks and resale issues, if you have the opportunity, surely the 4.0 RS is the path of least resistance. No doubt you've weighed the two in comparison.

When I researched the various 4.0 and other stroker and big bore upgrades, I encountered references to tuning and drivability issues as well as concerns about long term reliability, especially when driven, as is my want, at the red-line and often in searing track temperature conditions.

silverboy

Yes the ideal goal is to have increased power, reliability and of course the character of my old engine.

Manthey and Cargraphic who we all know and respect use their kits so hopefully I'm in the right direction.

The piston weights are lighter and will be using the stock crank so hopefully chances are I'll be able to achieve my goals.

Regarding the 4.0RS, I am in the camp of the 'new normal' in terms of the economy as PIMCO would say. Also my money tree is showing fatigue and my kids will be entering college in three years so reality bites.

I just have fun on having a project car. So far I've got Motons, GMG sway bars, droplinks/toe links, RG5's so I feel the car handles pretty well.

silverboy

Hi Alex,

I wanted to ship my engine to you but it'll take a month and back just on the boat not to mention the hassle of dealing with our corrupt customs officials on import duties.

Capricorn said they will machine and enlarge the critical water jackets...etc to increase water flow and keep it cool.

Thank you for your best wishes and as I said this is my only recourse due to living out of the land of milk and honey.

silverboy

Erik - no change in crankshaft. They will supply 105.4mm pistons and will change the sleeve.

CRex

Silverboy: this is definitely an interesting route. Being in HKG i have the same problem--Sharkey is too far away yet I'm skeptical of trusting the local guys to something akin to open-heart surgery. I'll be closely following your build!

So to clarify, the stroke of your rebuild remains the same while the bore goes up by way of thinner liners. Are there modifications to the block itself? How are you doing the ECU reprogramming?

You and I are in equally hot climate so it'll be interesting to see how you deal with longevity/reliability issues.

p.s. were you at Sepang last weekend when PCHK & PCS took out the track?

Serge944

This kit is proven. In fact, it was one of the first big-bore kits developed in so-cal by Wrightwood racing. The first engine built was back in 2003...way before sharkwerks started experimenting with increased displacement. I have not heard of a failure yet.

I'm using the liners from Capricorn as well, except the OP is using 106mm pistons while I'm using 105.4 for exactly 4000cc displacement. Good luck with the build!

CRex

Serge, with the bigger displacement what have you done to the intake tract? I wonder what's for show and what's necessary--the Sharkey guys haven't done anything to the OEM air tract, but the RS 4.0 obviously had the whole thing blinged to the nines...