Stroker build

[sailaz]

few months ago I couldn't find... now there is, and on aliexpress.com as well with even better price

[diesel des]

So just an update. Now the exhaust is quiet I can hear a small noise in third gear when on the overrun. So I will try rebuilding the s4 v8 gearbox I have that is noisy in almost all gears. I have a new input shaft and first gear for it and will change whatever bearings that are making the wine noise. I can then put that into my car and as it has a higher 6th gear than the rs2 box it will suit the stroker engine torque.

When the rs2 box is out I will strip it and find why 3rd gear is noisy and rebuild it.

Cheers des.

[cardcrash]

Wow! That's some mightily impressive power output, I can't imagine getting 518ft/lb's of torque... must really punch you in the back!

[diesel des]

Cheers. Yea 700nm torque is kinda useful. You need to be careful though as I have had it come out of roundabouts in third gear in a 4 wheel drift a few times . My wife thinks a bit less would do lol

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[Quattronaut]

Congratulations, that sounds impressive :-) 700nm...be honest: Little bit afraid when starting it?
It´s just what I took for minimal goal, but wanting to exceed it. Good to have someone to compare

Could you post something about the spool and pressure behaviour at highest gear?
Something like what you told us earlier

 0.5 bar at 2k rpm, 1 bar at 2.5k rpm and over 2 bar by 2.8k rpm.

may be with peak boost, and boost held at 6500/7000rpm? As accurate as possible :-)

It´s still 2,5L tall block diesel with EFR6758, what CR do you have? Some headworks or porting? Very nice power curve :-) Is it the final mapping?

[macspring]

My wife thinks a bit less would do, lol

You're lucky, I not allowed use what a standard oem S car has when we're in the car together.

[Quattronaut]

You're lucky, I not allowed use what a standard oem S car has when we're in the car together.

Thought that´s why we build them???

[diesel des]

Congratulations, that sounds impressive :-) 700nm...be honest: Little bit afraid when starting it?
It´s just what I took for minimal goal, but wanting to exceed it. Good to have someone to compare

Could you post something about the spool and pressure behaviour at highest gear?
Something like what you told us earlier

 0.5 bar at 2k rpm, 1 bar at 2.5k rpm and over 2 bar by 2.8k rpm.

may be with peak boost, and boost held at 6500/7000rpm? As accurate as possible :-)

It´s still 2,5L tall block diesel with EFR6758, what CR do you have? Some headworks or porting? Very nice power curve :-) Is it the final mapping?

Yes it's still tall block 2555 ish cc with 6758. I like the way it drives! Head is ported with new valve seats and supertec inlet and exhaust valves. I have played with the mapping since the power graph but just to change its driving style slightly as on the dyno it needed the boost played with a bit for peak power but on the road it would over boost.

The boost spool up points in 6th gear up a hill are as described. Typically full boot is normally at 3k rpm in lower gears and is 2 . 25 bar. Boost falls to 1.5 bar at 7k rpm. There is slight surge between 3 and 4 k rpm when over 1.8 bar boost but on the dyno increasing boost here to 2.25 bar didn't increase surge but brought up power and torque. The surge is only slight so not really a problem.

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[diesel des]

Yea my wife hates it when the turbo spools. Starts grabbing for door handle etc. She isn't a good passenger since she spun her mini Cooper once on a wet road.

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[A1QSHIP]

You're lucky, I not allowed use what a standard oem S car has when we're in the car together.

Yes, I get complaints from the co-pilot too. When we were first dating I kept hearing a "thump" from her side of the car every time she thought we were getting too close to another car. She was trying to apply the brakes! Started counting to three every time she would do that & put an end to it.

[Quattronaut]

Head is ported with new valve seats and supertec inlet and exhaust valves.

Stock diameter valves or bigger ones, with cutback or normal? Are the valveseats 3-ankle machined, combustion chamber machined?

The boost spool up points in 6th gear up a hill are as described. Typically full boot is normally at 3k rpm in lower gears and is 2 . 25 bar. Boost falls to 1.5 bar at 7k rpm. There is slight surge between 3 and 4 k rpm when over 1.8 bar boost but on the dyno increasing boost here to 2.25 bar didn't increase surge but brought up power and torqu

So 0,5bar at 2000, 1bar at 2500, 2bar at 2800and 2.25bar at 3000, down to 1.5bar at 7000 with very little surge between 3000 and 4000? That is driving like a TDI :-) That torque at lower rpm...Start in 1st gear, then switch to 3rd and then into last gear to stay there :-) everytime enought torque :-)

My girlfriend likes the turbopunch :-) sometimes she´s looking a bit weird, when I´m braking little late behind other cars, but when I hit the floor on free road, she "Yiehaaaas"´s like a Kid running around a christmas tree

[diesel des]

Your lucky to have a girlfriend like that!!

Valves are stock sizes but are cutback with 3 angle seats.

In 4th gear it is very useful as it pulls well from 40mph to over 100 easily. It's easy to get carried away with big turbos and high bhp numbers but I always feel that a wide power band at lower rpm is better. I think an efr 7163 would also be a great turbo on this engine with just slightly more lag and 525bhp. .. But that's chasing numbers again!

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[Quattronaut]

Jap, this powerband is in 90% of the daily driving more usefull and faster than a high peak power setup with 600+hp.
7163 would also be a great deal. I think your turbo is running nearly at limit from 3500 to 7000, that´s a hard life. Maybe here the 7163 won´t only give more power, but maybe more reliability- or safety feeling :-) but I can´t estimate how much more lag it has, so before loosing that driveability, I think I also would keep it as it is.

[sailaz]

Des, You have Main radiator and AC condenser at the front, correct ?

http://www.s2forum.com/forum/showpost.php?p=815866&postcount=51

[diesel des]

Yep stock radiator and ac cooler. Intercooler in front of them. Non stock bumper.

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