I'm not surprised too much by when it comes on with the 2860, that's only about 1500 rpm later than my almost identical HKS GTSS on my SR20. I'm surprised by how it noses over almost immediately! Something's wrong there - I know it's inlet restricted, but that's the sort of revs the 2l IPRA turbos are pulling through the restrictor. A 1200cc engine should be able to go to ~9000rpm through the 36mm restrictor.

If you are wanting power at an earlier RPM, wouldn't reducing the intake manifold volume improve that more than changing the turbo? After all, for a 1.2L surely that large an intake track would be overkill and hindering earlier spool up with all the extra volume to fill.

Good questions,

Topgears results were fantastic, i think the engines are similar and im only up about 25Kw on his carb, non intercooled setup.
Im using a Motec M800 but im not using any special fuctions on it at the moment. The reason i went with the m800 is it can control 8 injectors sequentialy, and i`ll need this for the bike headed engine. Any cheap ECU would do what im doing with this engine. The only thing ive set up a little diferently is MAP over TPS for the load axis. The bigger cam almost made this a must.
With the E85 and intercooling it likes about 3 degrees more timing than the 18deg that Topgear could use (21deg at peak torque).
Ive never put a blowby guage on it, im actually shopping around for one ATM.
It seems ok. It`s not pushing oil out. But i`d like to know blowby CFM.

Im looking into the power falling off fairly fast. The data shows the boost is still there and ign timing is good. I think it could be one of three things. The cam choice, weak valvesprings or the dump pipe where it joins the turbo. This pipe doesnt alow a smooth conversion of the waistgate gasses to the main exhaust flow. its bad enough to make boost creep a problem from about 5.500rpm.
Fixing that will be my next job. Im less inclind to think its the valve springs as power would probably fall alot faster than it is.
And yes, the restrictor is not coming into play.

Topgears setup was impressive for numbers, but werent you making much higher numbers before the meltdown than now?

Also remember been quite hard trying to turn that engine after messing all arvo trying to hook up the box. You mentioned it probably was the hard tension valve springs?.

The intake volume is large and probably too large. It would make a difference to throttle crispness/response but probably little difference to where boost come on. I think of it this way, the maifold volume is say, 1 cubic ft. and the engine is shifting say 120 CFM. Thats 2 cubic ft per second filling the manifold in half a second.
Obviously these are made up figures just to give an eg.

Im going to build another manifold with throttle plates much closer to the valves. it`ll be interesting to see what difference it makes.

I changed to softer springs when i went to the bigger cam because the big springs were binding at full lift.
Ive bought some better springs that wont bind, but i havnt fitted them yet.

The higher Hp number were on a dyno where the figures couldnt be trusted.
I hadnt finished my dyno then. I have calibrated my dyno and trust the figures.

Its always hard to compare figures from different dynos. Top gears figure was about 100KW ATW at 18Psi from memory. This one is about 125KW(165hp) ATW at 14Psi. I`ll do a run at 20Psi(same as i ran at PI) to see what it makes.

I took the datto with this engine in it to Winton on the weekend.
I thought i`d let a mate(very good steerer) race it for the weekend to get some feed back on the suspension etc.

We had a crank trigger fail at the start of qualifying, so started rear of grid for the first race.
Kane drove the car from 24th to 5th in the first race!
The car was understeering a bit so i made some changes before the second race.

With the understeer gone and the car feeling better Kane drove to second in the 10 lapper.

For the final race i gave him another 30-40 Hp, increasing to 19psi boost.

He finished second again. But smashed the long standing Under 2lts lap record by 3.7 seconds, doing a 1.33.9 lap!

I am continually amazed by these engines!!

Geeez all in a a12 with 19psi lol.
Good call getting others opinions for feedback on handling.

If only others game to do same in the lpg mobile lol. Taking liberties in dons words, can't polish a turd but even has more too offer than my car lol

First off- i take my hat off to you sikyne for this build...i love where its at and where your going. I have just sat down for about a hour and read through the whole thing (slow reader and some of the lingo is new) from start to finish.

There seems to be quite a few people throw up the question of 'how good would a a14-15 turbo be' and i think would there be a huge difference?

Also whats the background on this car? Did you build it and run it as a sprint/track car first or did you buy a car already built minus this engine set up.
Top work mate and you have some impressive times around winton and the island. Keep it up
Thanks for sharing it all

Congrats on the lap record, that's awesome!