Markus L
Veteran Member
My 1.9 VE made over 370 bhp with just slightly ported head so why CR wouldn't do big power? These are not naturally aspirated engines so if you want more air just add boost. 2260 is not even near to choke with 250 bhp.
Not me, i'm still reading, all this is very good info.I literally give up.
Clearly some people are beyond reading.
16 valve heads easily outflow even slightly ported 8v heads. Problem with those is valve control when having increased flow on boost and emp. Luckily there is a fix for that. gtb2260vk is indeed good for 300+ hp so plenty of room there.My 1.9 VE made over 370 bhp with just slightly ported head so why CR wouldn't do big power? These are not naturally aspirated engines so if you want more air just add boost. 2260 is not even near to choke with 250 bhp.
Well, this kind of basic stuff like stiffer valve springs should be done before you judge the head is too restrictive. Of course if you ask vendors what to do they recommend head porting and lots of other stuff they want to sell you. I think it's just wasting money.16 valve heads easily outflow even slightly ported 8v heads. Problem with those is valve control when having increased flow on boost and emp. Luckily there is a fix for that. gtb2260vk is indeed good for 300+ hp so plenty of room there.
No need for bigger turbo, GTB2260VK is good for 300+ bhp.Johan has consistently gotten 270 to 280 hp on his cr tunes. He would also agree that 28xhp is the flow limit of the head. You can put a bigger turbo on to try and push more through but emp just goes much to high for gains to be reasonable. The emp will have direct impact on peak cylinder pressure and how long your engine will last before it destroys itself, for those who think just putting a bigger turbo is answer.
It's quite obvious that you don't get any gains with regrind cam if valves are already floating. I agree that a headwork needs to be done; stiffer valve springs are definitely needed.As already pointed out, head work is necessary. Johan and myself have already test a regrind cam on OEM head and it did not help. There has to be head work done to support the cam grind. Head work includes valve changes.
What is it exactly then?Like pointed earlier the problem is not in the head flow.
Not me, i'm still reading, all this is very good info.
You have a very nice car btw... congrats.
I've reread again your build thread, so with your set-up you'r still running on Lambda calculation in the ECU?
The only thing I find strange, is the linear figure of what's supposed to be maxed out, the VE efficiency of that engine is not linear, when there is not enough air, you should have more and more smoke as the RPM increase.
I'll be curious to see VCDS log of the various fueling parameter of your car.
I think you need to reread my post. Gtb2260 is good for more than 300+hp on lots of engines but not on OEM cr engine. You missed my point.No need for bigger turbo, GTB2260VK is good for 300+ bhp.
It's quite obvious that you don't get any gains with regrind cam if valves are already floating. I agree that a headwork needs to be done; stiffer valve springs are definitely needed.
#68 onwards for example.What is it exactly then?
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umm, on my vm 2.8, It has the cp3 pump. It's also timed so the impulses coincide with TDC. You better believe there are impulses.. even with the internal cascade type pressure valve, it does have variance. Ever put your bare hand on a common rail when it's running? By statingIt seems you just want to make things complicated when they are simple , reliable and work well already.
Pump piston and TDC events are not important in multi piston pumps. 2nd piston is always off and this would mean it has no sense, its a parasite.
Instead The entire system works as an accumulator of pressure, i'm told they teach this in mechanics university here where they study this stuff.
Also rotating the pump at half the speed just because you imagine there is a cavitation problem might not get you far.
Right.#68 onwards for example.
Read again. Valve control ... Indeed more boost will fix itRight.
I believe the shaft on the VM 2.8 cp3 is keyed such that it can be timed to injection events. I doubt it makes any real difference though. The fuel rail probably absorbs most of the pump pressure wave pulses.Would be nice to see a print of that manual stating how to time the CP3 LOL
There are no marks on the cp3 to align it ..so how do you do it? Please enlighten us once more.
Maybe you open the head and put a dial gauge inside and bring it to "tdc" ..but then you torque the bolt it goes bananas for sure ..
Good point, and I wondered about this (reduction of possible underhood noise) a couple years ago after watching hundreds of posts on this exact same subject on Lostjeeps.comWhy VM wanted to clock the cp3 on their 2.8 is a bit of a mystery. One theory is that it is for NVH, specifically that the pump operates slightly more quietly when the pressure pulses are timed to injection events. I don't think you'd see any difference at all on a dyno.