kpr's starlet

[Roman]

True good point! Didnt think about overlap. 

[kpr]

maybe plausible its avoiding fuel going out the exhaust.  orange is rough injection window at 9500rpm.  around 4ms.   some guesstimation and poor math says would take almost 1ms more to get to intake  valve.  but that doesn't take into account the intake valve would be shut at the time.  and making it out the exhaust valve for that matter

It did have a bad day when running at 300 but mostly through the low/midrange. lost all the power.      possibly didn't like the fuel hanging around in the intake port,  rather than going out exhaust.    who knows, maybe majority of the fuel is going through on the overlap and mixes  better.    Interesting there is something in it though.  have tried in the past with smaller cams and didn't do shit so left it locked to 400.

 

[Roman]

@kpr I think the numbers on your otherwise magnificent MSpaint diagram are the wrong way around...

So 450 BTDC end of injection means its happening earlier in the cycle not later

[kpr]

Ah yes, that was the part i wasn't sure on.     out of link manual, should have scrolled down further.   kinda makes more sense, kinda doesn't  

 

 

[Roman]

Man this thing sounded awesome! 

So cool to see it back after a long break from drags, and 13.2 / 105.5mph in those conditions is friggen flying. 

Well done. 

[rusty360]

Bloody hell over 200hp N/A!

That's farking awesome man!

I need to read back though the thread and YouTube vids but what do ya reckon it would cost to build that engine?

[kpr]

Nothing too exotic in the engine itself, other than the vvti setup of course. All off the shelf parts in the bottom end.    Head mostly the same. but is a bit of money in getting the bigger valves in there. new seats and stuff.  Once start adding all the  supporting stuff on guess is going to be pretty spendy. dont really want to add it up haha.  If counted the time Ive spent on it, that would be by far the biggest cost

[Roman]

I know that this is a punishing request,

But it would be interesting to see how good the fuel economy can be with your vvti able to go into prius mode! 

Would be cool to: 
Drive at 100kph and see what load/rpm you end up at. 

Go to this load/rpm on the dyno and see how much horsepower is needed for cruising. 

Then adjust the vvti / ignition timing / air fuel to see how little fuel you can use to acheive this much horsepower. 

Might be that you can dethrottle the shit out of it by retarding the cam by heaps, so make 30hp at 70% throttle or whatever 

Will really get some internet people mad if your car gets exceptionally good fuel economy as well, haha.

[kpr]

I get asked punishing requests every day.

just happened to read this before going to fill up at gasser.     absolute zero effort to tune any thing for economy. and its borderline tuned properly for cruise atm.    but put this here for reference next time is on dyno as i'll forget the numbers.  
yeah it pulls 4000rpm at 100k.  so never going to be prius spec haha.
its like a cyclone out, and road wasn't completely flat  so somewhere.   ran it both ways.  probably 8.5% throttle is 100k on dead flat.   vvti 40 degrees.   so have 40 to go full prius/retard.

the dyno hp readout doesn't have enough resolution to do cruise stuff.   but using the torque numbers  and running in a lower gear to mulitply the torque, for more resolution  works well.

 

 

 

[BiTurbo228]

Man that's impressive! A mate of mine has a 106 GTi race engine which is a not entirely dissimilar 1.6l, great flowing high revving engine. I thought his one was doing well making 197hp @ 8300 crank (147kw).

On the VVT front, I wonder if you knew off the top of your head whether the pulley diameters were the same for the 16v and 20v VVT cams. If it is, then there's a slight chance that I might be able to pinch a 4AGE pulley for my 70s Rover 2600 engine (seems to be the same OD as the 16v 4AGE pulleys). I've been searching around but found a lot of conflicting information, usually regurgitated by people who haven't come across the real versions themselves.

[kpr]

sorry just seen this.  the cam pulley sizes are the same between 16v and 20v engines.   36 tooth.     is the bigger round tooth pitch.  i forget the numbers now.    I couldn't find much that  matched to pitch and tooth count when was hunting for pulleys awhile back.  most were 40 tooth. or the smaller pitch

[Dudley]

Wadiyatalkinabeet

[BiTurbo228]

Love that your 'midrange' is about 5000-8000rpm 

[kpr]

Was slightly intimidating pulling 10k after having the 7a in there,  that was lucky to do 7500rpm

[sheepers]

I am continually blown away by the never ceasing progress you make with half an engine. 

Great work man,  just great. 

[Dudley]

Pretty good gainz for a crusty old 7age

[shrike]

@kprwasn't sure what thread to throw this in or if youd be interested but Barry has the below for sale

Can't remember if your running factory pistons or not

[kpr]

I run toda pistons.      wonder why he took them out haha

[Dudley]

He took them out cause he’s building a 9age that’s 11k rpm capable