I5 extreme! spoke with jonus about my engine, and general discuss

[vcosmin]

Dutter racing, has listed 9200 rpm, in his 2.5 stroker, it has a gt42, now upgrading to something larger , curenttly around 1000hp. Also, i have my engine unopened for 2 years, and still holding, reving to 8500rpm, rpm and sometimes hitting 9000rpm (first gear) with 95.5 cranck and long block. For rod ratio, there are some high reving hondas with 1.5x ratio, like type R B18C , and it holds fine. So it works, but depends on if is worth it or not, maybe with a close ratio gearbox in 8500 rpm, is more than enough, for almost any turbo setup.

[my2000apb]

At high rpm there is no problem wit filling the lifters with oil. The problem are the springs - they cant return the valves. That's why we put strongest one. And the valve seats - to do not burn, or/and make valves jump. That's why we use beryllium copper. For guides too. That's my opinion...

i have to agree with Repo, the hydro lifter is done at ~8500

[repo]

Does anyone have any footage or dyno plot from Dutter, again, I am not actually doubtful, but just there are so many myths of this type on the web.

I know Kalsket revs his 95.5 stroker 8k+, but I have not heard of 9000rpm revs with stroker. And like Vcosmin said, usually it does not really make any sense to rev that high.

Attached a plot of Paavola's 2.2 liter engine. Turbo is Holset HX60 mfs, 81mm compressor, 86mm turbine. You can see we need to rev over 9k.

[vcosmin]

http://www.youtube.com/watch?v=5VQmIpP59dg

http://www.dutter-racing.at/garage

But you cannot see very clealry. I the specs is stated 9200 rpm, but knowing what gearbox he uses, and diffs, you see that is hitting revlimiter around 400m
http://www.youtube.com/watch?v=2z-iKhOu3FI -
around 265 kmh, that only give around 8500-8700 rpm, depending on tyres.

[|CL|NIKI]

i have to agree with Repo, the hydro lifter is done at ~8500

Agree with that - for me 8500 are high. And Yes - from 7500 to 8500 You can use stronger springs with hydro lifters but that is.
Up than 9000rpm is extreme even with mechanical lifters and they are strongly recommend!!!

[|CL|NIKI]

repo - what about using 100mm crank?

[quattro84]

Who did Dutter's head? TK motorsport? I can't believe a stroker will flow that much at those high rpm's, so no need to go there.
Inertia on strokers does not seem an issue then these days?

[|CL|NIKI]

What is wrong with the stokers? If the head (bottom too) is prepared - why not?

[terrybullwon]

Piston speed goes too high.

[|CL|NIKI]

Thats true....
Than how We can run for example GT4202 - need displacement or high RPM. Which is better? Ive seen many projects with booth done it + high boost (more than 2.5 bars)....

[Rocco]

Thats true....
Than how We can run for example GT4202 - need displacement or high RPM. Which is better? Ive seen many projects with booth done it + high boost (more than 2.5 bars)....

There's not replacement for displacement

[terrybullwon]

2.5 bar is not that high. Paavola drives with 4 bar boost.

Yes, that's right. 5 bar absolute.

[my2000apb]

2.5 bar is not that high. Paavola drives with 4 bar boost.

Yes, that's right. 5 bar absolute.

badass

[quattro84]

Mean/max piston speed is high but due to material quality improvements acceptable since it does not run much in that region.
I'm more concerned at max acceleration overstraining rod bolts messing up the clearance & deforming the rod bore, shearing stresses on the small end for both rod and piston pin.

[|CL|NIKI]

2.5 bar is not that high. Paavola drives with 4 bar boost.

Yes, that's right. 5 bar absolute.

That's why I told more than 2.5.
2.8 - 3..... will be good. I believe don't need so much like 4..... Which is crazy.
I know about garrett special made gt 42 with four bearings, capable to make a little more than 6 bars boost...