420+bhp project

[Lee]

The impending remap is not the begining or the end of my mods, it is just something fun to do that's not that expensive and it will mean that I don't remain a mobile chicane during trackdays. Only done one but I am hooked! Just bought a helmet too!

I am going to miss out the 300-500 bhp steps. The bottom end is going to be strengthened and the oil system, exhaust, head, intercooler etc etc etc will all be changed in anticipation for the 'well over 600' magic figure. I need to make some changes to get some 265s under the arches which is going to be incredibly expensive and laborious....Even before I strengthen the engine I have lots of stuff to sort on the chasis. There will be lots of hardware being upgraded without any additional power added for quite a long time. Then, overnight (not quite) it will be monster turbo, monster injectors and reamp. My car is my hobby and the project will take a long time. Preparation is the magic word for me. I estimate the project to cost in excess of 25 grand UKPounds altogether (10k for all chasis mods and about 15k on the engine/gearbox!!) so I don't want to spend loads making small steps just to throw them away for a little bit more a short while later.

The magic figure is in excess of 200mph, I guess, but that will need about 700bhp+ and some major aerodynamic changes to maintain stability at high speeds. And, before anyone asks, I do anticipate rebuilding the engine every 10,000 miles or so. By then it won't really be a road car although it will be perfectly road legal.:wacked: :wacked: :wacked: Trackdays, rolling road shootouts, quarter miles, shows and meets only....no commuting!!!!

[Pisobiker]

You're gonna get serius than, Lee

Just not to loos too much track over you, bunch of tuning maniacs, I just brought to my garage my new 2.5L block yesterday

Got it from a local braker: block complete with crankshaft, conrods and pistond (the latter totally useless, of course), for 400 euros. everything seems pretty good!


Marco

P.S. If my wife will ever happen to discover how I'm waisting my money....

[Doug_RS2]

FFS - will you guys stop moving the goalposts

Supercharged 2.5L monster turbo S2 - bring it on

[Pisobiker]

Originally posted by Doug_RS2
FFS - will you guys stop moving the goalposts

Supercharged 2.5L monster turbo S2 - bring it on

The supercharger stopped at the "brackets". Got it fitted in (3B "mannequin") together with new positioning of alternator. Still looking around for the SC inlet and outlet aluminum ducts for it.
Could find a way to custom build them, but would like to avoid the hassle....




Marco

[Lee]

What bore and stroke does your 2.5l bottom end have? I will increase capacity but don't want to increase the stroke....I know I would get much more torque but I want a verry revvy engine. Target is 10,000 rpm....hence the anticipated frequent rebuilds! Ti valves and solid lifters too.

@Doug, mate, the goalposts haven't moved for me. I just put them where I wanted them from the begining. My aspirations are very high!! I just want to show what can be done if it is done right. Anything is possible given enough time and/or money! I really like the idea of the ultimate 5 cyl engine and that's why I discounted the V8 transplant from an RS6...an even bigger mass in front of the front axle would be really bad!

I saw a picture once of an S2 with an S8 engine in. Anyone have the picture because I have searched high and low for it recently without success.

[Doug_RS2]

Lee - the ultimate avant would be mid-engined would it not ?

[Pisobiker]

Lee,

long stroke of course doesn't allow high rpms.
Pistons average speed for the stock 86,5 mm engine @ 7500 rpm is already 21,625 meter per second, while on the 95,5 mm stroker @ 7500 rpm it will rise to 23,875.
those are already high values. On a NA engine 24 meters per second will already be a limiting factor for correct "breathing" of engine (above this average piston speed there isn't appreciable flow increase due to the reaching of sonic velocityes in the most critical port's sections).
On a forced induction engine those values could be slightly increased, but not that much.

Take into account that the 86,5 mm stroke will have 24,508 meters per second average speed @ 8500 rpm.

Short stroke engines will of course be superior as for top end power, but as many knowledgable people on this forum (Siena, for example) said, bore is already at its max safe limit. higher bore will not allow to run extremely high boost levels due to too little gasket among cylinders.


Marco

[Lee]

Too much agro with the powertrain! I want to keep the 4 wheel drive, 5 cylinders and seats for 4 people!

Here is the really silly suggestion (I wouldn't even consider it but it would be MAD): Lambo V12 from a Diablo VT. Gearbox in front of engine. Diff just behind it. Small diff up front for the front axle. That is a really beatifully packaged engine and transmission system. They put a lot of though into it. Bloody big engine though and it must be really heavy too. www.douglasvalley.co.uk had a diablo in for breaking some time ago too. I originally was going to fit front and rear brakes off a Diablo but the replacements parts are even more ludicrous than my APs. I looked into it for a long time but disks and pads are almost impossible to second-source. Some makers do aftermarket pads for the Diablo and they weren't that bad really. The disks were the killer!

[Lee]

There are quite a few alternatives to head gaskets. The parts are off the shelf. Its the application that needs a lot of work.

The acceleration of parts is a bigger killer than the avarage speed of the pistons. A large chunk of my degree was engine design and we did a lot on analysing the dynamics of cranks, pitons and rods, fatigue limits etc.

[Pisobiker]

Lee, since the time I bought my ABY S2, thus having the full 3B setup available, I have continously dreamed about building a 72° V10 .

Main issues always where:

1) crankshaft for putting two conrods each journal;
2) cutting modifying and welding togheter the two blocks.

But now that Audi did the V10 TDi.
95,5 stroke 81 bore !! Does it ring any bell?

If the heads could match over the cylinder, could even be possible to run the two banks (dunno if it's the correct term) separatrly with two looms and ECUs.

700++ easy HP and 1000 NM


Marco

[Lee]

This thread has majorly digressed, sorry Doug. This was meant to be about Dougs impressive upgrade and I have taken it off on a tangent! Oooops. I'll shut up.

[Lee]

Originally posted by Pisobiker
Lee, since the time I bought my ABY S2, thus having the full 3B setup available, I have continously dreamed about building a 72° V10 .

Main issues always where:

1) crankshaft for putting two conrods each journal;
2) cutting modifying and welding togheter the two blocks.

But now that Audi did the V10 TDi.
95,5 stroke 81 bore !! Does it ring any bell?

If the heads could match over the cylinder, could even be possible to run the two banks (dunno if it's the correct term) separatrly with two looms and ECUs.

700++ easy HP and 1000 NM


Marco

Mmmmm. Now that sounds interesting! That Toureg engine and transmission is well impressive for a production vehicle.

[Pisobiker]

My engeneering studyes where not specifical on endothermical engines, but I did extensive research on them by my own.
Accelerations can be kept low using longer rods, and inertial forces (the most dangerous on high rpm engines) can be fought with lighter materials.
What I was talking about was bare "breathing" of the engine.
There is no gain in making the engine rev up to 10k rpm if above lets say 8500 rpm you cannot obtain any flow increase.

Just a thought.

Originally posted by Lee
There are quite a few alternatives to head gaskets. The parts are off the shelf. Its the application that needs a lot of work.

The acceleration of parts is a bigger killer than the avarage speed of the pistons. A large chunk of my degree was engine design and we did a lot on analysing the dynamics of cranks, pitons and rods, fatigue limits etc.

P.S. just edited because I got a sudden enlightenment on the right "past tense" for "fighting"

[Pisobiker]

you're right Lee.

Sorry Doug

Those are very interesting topics (for me, at least) so we may furtherly discuss on another thread.



Marco

Originally posted by Lee
This thread has majorly digressed, sorry Doug. This was meant to be about Dougs impressive upgrade and I have taken it off on a tangent! Oooops. I'll shut up.

[Sweeper]

You can take it to dream mods. I won't argue