Another "Stroker" Project

[Billman]

I read the table with the comparisons of 3B, Vasislis and Justin's engine and wonder how the ~30% increase in max piston speed (and friction) is possible. there must be further treatments to the cylinder surface to go with that. To me that is one of the most important figures to look at.
Anyway what sense does it make to have big torque @ low revs and not using that to excess and go for high RPM's? I notice my driving style is that I very seldom even go over 5500 and rather ust the torque @ lower revs. I only have a chipped ABY. It is not allowed to drive in 3rd gear @ >5000 here in Switzerland. Even on the highway.
The administration invested heavily in speed cameras everywhere across the country.
Another point I would like to discuss is driveability. With the new F430 Scuderia it is possible to change gear in 60ms. This means the engine must change revs that fast. My ABY feels sooo dull reving up & down. A lighter flywheel and other litghter parts in the engine can improve this but how much? Sure I can change gear quickly but soon I will have to replace engine and gearmounts at least. I don't want to lash my baby.

The original Engine has 21.62 M/s Piston speed. My engine is going to have 23.9 M/s. this is an increase of 10 percent. This increase is minor and with the margins of the general rule of thumb not to go over 25 m/s.

Either way it has to do with moving mass and interia load and not with friction. About the friction the Rod/Stroke ratio is crucial. There i am also going to be in the "green" region.

About the 60 ms gear change. You own a Ferrari or do you want to install a Ferrari gearbox on the S2?

P.S.: Am Grüsch bin ich mitgefahren bei einen 530+ Lehman RS2. Die geschwindigkeit regelungen sind nur für die Haupt-Autobahnen.

[Billman]

Any details on those allroad gearbox mounts and the modification required to fit them?

I already installed them. There is better feeling but i dond feel at this point a very big difference. Maybe if i had more horsepower it will be more noticable. When i had both on my hands the difference was very big. They are much harder than the original ones.

in order to fit them you must remove the metal plate from the Allroad mount and place other ca. 5mm thick washers with a smaller diameter. You also need 2 new bolts. Appart from this they fit right in.

[fendent]

Meeting in Grüsch and others

About the 60 ms gear change. You own a Ferrari or do you want to install a Ferrari gearbox on the S2?

Unfortunately I don't own a Ferrari. But a gearbox operateable from the steeringwheel in my S2 would be great.

P.S.: Am Grüsch bin ich mitgefahren bei einen 530+ Lehman RS2. Die geschwindigkeit regelungen sind nur für die Haupt-Autobahnen.

I know which one you mean. Last year Urs took me on a short ride with his red Sportq. that has the prototype engine from the same company installed. Very impressive car. Also the themal management under the bonnet is by far better. Riding hard and stopping. The radiator does not need to cool the bay.
After the meeting we went on a tour and I was not able to follow at all with my car but enjoyed the passes massively.
To all the other folks here I highly recommend to come to Grüsch next year. You won't regret it.

[caterpillar]

very NICE project billman!!!!

[Billman]

Thanks! Prob is i dont have a space (garage) where i can mod the car whenever i want. Thats why it is moving so slowly forward.

[Billman]

UInfortunately not

I am going to look if i had any pictures.

[GazzaG60]

nice project.

holset hx turbos are regarded as being at least on a par with a garret GT. problem is they are mostly made for diesel's and big ones at that. my mate used to make them for the huddersfield factory.most cars we have over here are under 2l and only really the hondas have enough flow for these. ive seen 1.6 and 1.8 hondas running mabe 500-600hp with these. maybe hx35s

[Billman]

HX35 is a ta dsmaller than mine but with all the High tech gimmics : Extended Tip, Map enhanced groove etc.

Regards

[maRS2]

Billman you seams to have study the holset option's.

Do you think a Holset HE300 or HE400 could be fited to our car's?

The vnt system seams much stronger than the garret one.
the turbo look also to be watercooled so might be able to cope with the egt from a gazer.

next question: would it be possible to wire the electrique acruation directly with the N75 wire and then with a remap control the boost that way?

Sorry to highjake your thread.

http://www.holset.co.uk/files/2_1_2_...et%20HE300.php
http://www.holset.co.uk/files/2_1_2_...et%20HE400.php
http://www.holset.co.uk/files/2_5_1_5-VGT.php

[Billman]

I was also thinking about it. Not the N75 but the Holset VNT option (problem is i dint find any in a reasonable price). The E400 seems to be closer to the HX40 i have.

The think one should consider is that the VNT option is nice and well but there are also limitations. The Turbine is VNT but the compressor not! This means that it could surge in low RPM because with the smaller turbine exducer it will spin faster thus providing more air than the engine can take. If it goes like this then you must open the VNT further so at one point the VNT positive side is away.

[maRS2]

But this turbo offer all the feature from the holset like the Antisurge ....

[Billman]

Yes but antisurge doesnt mean that it doesnt surge but that it prevents surging to a certain point. I believe though that it would be nice to find and try something like this out.

[maRS2]

So i should find a turbo flow map for those to check where is that surge line

[Billman]

Yes the that what we really would like is a turbine map. I think that that with a VNT you have the posibility to be nearer and easier at the perfect turbo that with a non-VNT.

We must see. If find any Holset VNT at a good price i would get it.

[Billman]

Yes Jamo is right at this point. Internal Porsche informations claims the same at the designing of the new 911 Turbo engine with 2 KKK VNT Turbos they have had many reliability problems. The only hope there is that the Holsets we are talking about seem to have a more robust VNT than the Garrett. They are also big diesel engine turbos and not like the small Garretts found i.e. on the VAG 1.9 TDI.