Which Stroker Kit

[323GT-R]

The standard turbo can make way more than 1.2 bar... BUT! Boost doesn't neccesarily make power, the important factor is the MASS of air. As a general rule of thumb, more boost will produce more torque, but it won't always produce more power. To make power, you need the mass of air to be high at high engine speeds, and this is where the restrictions come into play.

You could take a bog stock GTiR, stock exhaust, stock fiter, stock everything, wind the boost up to say 1.4 bar, and probably end up with less power than if you for example fitted a decent exhaust, filter, front mount, cams etc and only ran 1 bar boost still on the stock turbo On my own car, I've gained a fair bit of power without increasing the boost, all through paying attention to all the small details of maximising the amount of air that can flow in and out of the engine.

The stroker kit does only increase the capacity by 10%, but due to the altered rod / stroke and bore / stroke ratios, the whole characteristics of the engine are different. The standard turbo is now mis-matched with the engine, which is crying out for a big turbo... :lol: It's hard to say what exactly is the situation with Ed's stroker on the stock turbo, but my guess is because the stroker produces more low down torque, it's feels less powerful than it really is at the top end. It seems strange that injector duty is higher in the mid rpm than the top end though :?

 

[J-GTi-R]

Again I already understand the turbo theory and why Edd needs the 3037 to make full use of his stroker kit and why there's more to power than just more boost but....

If in Edd's case the head is not the restriction over 5.5k rpm at only 0.8 bar, all I'm saying is it isn't going to be the turbo either because the turbine wouldn't be restrictive at 0.8 bar on a 2.0l engine and even with the different characteristics afforded by the rods and crank etc., at a 10% increase of capacity it's still not going to be expelling that much more exhaust gas to cause excessive back pressure in the exhaust manifold due to a restrictive turbo.

 

[323GT-R]

By the same token, how can the head be the restriction, when other people are running more power with the same head? The head is surely less of a restriction than the standard turbo...???

 

[Nad]

Just a quick note to add, Turbo Dynamics said my 2.2bar turbo would max out at around 1.6bar with the stroker kit. If the stroker consumes more air at higher rpm than the turbo can supply at 0.8bar would this not be the issue??

I prob missed something out as I got lost a few pages back :lol:

Nad

 

[dpmc21]

Hey guys,
Sorry if what I'm saying is totally wrong as I don't claim to be a whizz with this stuff, but I had similar problems with my car to what edd's was having and I only have a standard 2.0L with the following mods. HKS cams, forge front mount, boost solenoid and controller and standard turbo, now when I ran it a 1.2 bar it struggle and hesitate at around 5000rpm up untill gear change (say (7500) Now I spent a lot of time and money on trying to figure out what was wrong, plugs, leads etc even a rolling road, but fueling etc was spot on, now just over a week ago I had a Greddy TD-06 turbo + manifold + external wastegate fitted and guess what disappeared all the way through every gear, the hesitation. Why is that, I dont know but I can only say it must be due to the bigger turbo. I had my standard one checked and it is in mint condition so why it did this I don't know. Any ideas???

Dom
www.justinks.co.uk

 

[Fast Guy]

Maybe it's something to do with compressor surge/stall?

 

[J-GTi-R]

By the same token, how can the head be the restriction, when other people are running more power with the same head? The head is surely less of a restriction than the standard turbo...???

Yeah, I have realised through this discussion that the head isn't realistically going to be the restriction, but others have then said it must be the turbo then, but at that boost I doubt it would be that either.

Just seeing if anyone has a conclusive answer really.

 

[J-GTi-R]

Just a quick note to add, Turbo Dynamics said my 2.2bar turbo would max out at around 1.6bar with the stroker kit. If the stroker consumes more air at higher rpm than the turbo can supply at 0.8bar would this not be the issue??

I prob missed something out as I got lost a few pages back :lol:

Nad

Not really as if the engine was consuming more air than the turbo could supply, you'd see a drop in boost.

 

[Fast Guy]

Not really as if the engine was consuming more air than the turbo could supply, you'd see a drop in boost.

Would you tho? Wouldn't the wastegate actuator sense this drop and keep the wastegate closed longer to supply more air? but wether the standard turbo will still supply enough air or not I don't know :?

 

[MarkMc]

When I was looking at getting the motor rebuilt I asked the tuners about the strokers last year. They said to add another 20kAus to the engine rebuild to get it done properly and that would only use blocks from JUN. They said there are issues with sleeves floating .

Just for interest(Mark’s believe it or not) :shock: :shock: :shock:
The last time I picked my car up they actually had a 200sx with the stroker( Full JUN) kits in it, but were talking BIGk motors with 1000HP laugh if you will. But they also said these engines don’t last long.
They also had a GTR just behind my car lazily turning up 509 kw :shock: at the wheels on the dyno ( I was looking over head to see where the jumbo was going to land) while over in the corner they had Honda Civic with 800+hp :shock: and should not forget they also has a 8.7 :shock: second 200sx(more powerful 1000+) sitting next to my piddly little GTIR with just 190 kw at the wheels. F :shock: :shock: k they had some cars in that garage

 

[J-GTi-R]

Not really as if the engine was consuming more air than the turbo could supply, you'd see a drop in boost.

Would you tho? Wouldn't the wastegate actuator sense this drop and keep the wastegate closed longer to supply more air? but wether the standard turbo will still supply enough air or not I don't know :?

It would stay closed longer, but if the turbo is the restriction, then even with the actuator fully closed, you still wouldn't be producing any more boost than it could manage. If 0.8 bar was the absolute maximum for the T28, then as the engine continued to rev, it's demand for air would then drop the positive inlet manifold pressure. 0.8 bar isn't the limit for a T28 though, hence my questioning the turbo being the restriction.

 

[323GT-R]

This is where the turbine restriction comes into play, as the back pressure rises in the exhaust manifold, the intake pressure doesn't always drop away, however you still end up with less mass of fresh charge air in the cylinders, as the engine is having to work harder to expel waste gasses.

BTW, i'm only suggesting ideas, not saying they're right or anything!

 

[J-GTi-R]

Yeah that would work at the limit of the turbo, but 0.8 bar isn't the limit of the T28 regardless of what's pushing air through it.

I'm only working through ideas as well, I certainly don't have the answer but it would be interesting (for me at least) to find out what the answer is.

 

[Nad]

Yeah that would work at the limit of the turbo, but 0.8 bar isn't the limit of the T28 regardless of what's pushing air through it.

I'm only working through ideas as well, I certainly don't have the answer but it would be interesting (for me at least) to find out what the answer is.

But maybe it is the limit with the stroker. Just going back to TD comment, which was that a 2.2bar turbo would max out at 1.6bar.

The T28 may be able to run 1.4 but maybe on the stroker its maxing out at 0.8bar for the same reason why off the top of my head I can remember the explanation.

Nad

 

[J-GTi-R]

It's a possibility certainly, but is it really going to be the reason at only 0.8 bar?

 

[Nad]

Been sitting here and still can remember why and its starting to bug me now.

I think I will have to mail TD and see if they can help.

Nad

 

[J-GTi-R]

yeah let me know what they say.