Tuning turbo time!

[Munkul]

so, we agree then. 9's are a good choice, which is what he went for in the first place

Remember - NGK's grading only goes from 2 to 12. I hardly think his engine needs the coldest grade available! When most turbo engines run 7 to 8 anyways!

 

[fingers99]

And most turbos run antilag?

I agree on the choice (with reservations). But the method, and logic.............. and see here.

It's a really ambitious project, worthy of much respect, but (given that something is bound to go wrong) I'd like to learn from what really goes wrong, if you see what I mean.

 

[craigb244]

I just dont know why you say im comparing my engine to a t-jet. ive never once compaired them.

anyway noticed something funny today. on the 8v at idle the turbo would spin pretty slow... (easy enough to stall it with your finger by touching the end of the shaft)

on the 16v and with a much larger turbo you would expect it to be slower... but the turbo is going like a nutter at idle. you can hear a faint wizzing and it is pumping out a considerable amount of air.

very odd

 

[fingers99]

I just dont know why you say im comparing my engine to a t-jet. ive never once compaired them.

Because:

I have a 1.2 16valve engine that I have fitted a turbo too.

I need to find out if the spark plugs in the T-jet have the same thread and length as the normal 1.2/1.4 16v engines.

I expect them to be identical (after all they are all the the same engine)
I have done lots of research and the only thing I have found is that they are 1 grade colder (which is to be expected for a turbo engine) and that they are iridium.

So, in substance and logic.................

But we should bury this here. Peace?

anyway noticed something funny today. on the 8v at idle the turbo would spin pretty slow... (easy enough to stall it with your finger by touching the end of the shaft)

on the 16v and with a much larger turbo you would expect it to be slower... but the turbo is going like a nutter at idle. you can hear a faint wizzing and it is pumping out a considerable amount of air.

very odd

But the new tub is a BB one, is it not? If so, I'd expect, at idle, that the drag on the journal would be much greater than the drag on the BBs. Still, the effect probably wouldn't be so marked just off idle.

 

[craigb244]

ah i see but i did mean as in engine design in which they are identical... they are all fire based engines.

but no mine is nothing like a standard t-jet... mine has a smaller displacement/higher flowing/better design manifold (anything beats a log manifold lol) and a larger turbo/much lumpier cam (specs i found show the t-jet to be very tame)



as for the turbo...no its not a BB turbo. but i guess that compared to the old astra turbo it is much much more modern and efficient...

 

[fingers99]

Could well be more efficient and etc. But I suspect the better mani may have some impact, too. Be ininteresting to see where the boost comes in -- my guess is that the biggest reason for the 8v cars becoming unmanageable is/was the horrible boost (and consequent torque) spike at around 3.5k rpm. So, what's really needed is coming in early, but gently, with a gradual torque/power increase.

 

[craigb244]

IT LIVES!!! took it for a few laps around the block... no problems

yet to weld a silencer on the waste gate so it is loud (scremer pipes really do scream.) but not as loud as i thought.

the power output is VERY smooth compared to the 8v but right now its running way to rich (using munkuls maps with the required fuel bumped up) and has an on throttle misfire. oh and the throttle only opens 60% because ive yet to mod the cable so hard to say what it will be like. but so far im happy

 

[fingers99]

The other day I did some googling on WW2 aircraft. Looks like one (maybe the) first use of the rear mount turbo was the P-47 Thunderbolt. Whatever the limitations of the system on a car, the T'bolt was probably the most sucessful high altitude fighter of the period (and one of the most loved by its pilots).

Great that it's mobile. Keep up the good work!

 

[craigb244]

ill get pics and video tomorrow

 

[craigk]

gongrats craig
cant wait to see the pics and vids

 

[craigb244]

no videos im afraid... wont be any for a while... got more important things in life to sort out now.

all I can say is the waste gate has a 0.5bar spring in it (so low boost) and atm at anything above 70%throttle and 3500rpm the engine has a massive rich missfire thats like hitting a brick wall but up to that point the car accelerates faster then the 8valve ever did, even when it ran at 3bar due to a split hose.

it is truely fecking rapid.

 

[craigb244]

 

[blu73]

there really should be more white cinqs.. I always wanted one

 

[fingers99]

I'd not realised you'd put the TB on that side -- makes for a shorter, cooler path from the intercooler. I've even thought of cutting a hole in the wing to accomodate the pipe! Strange how white Cinqs look good, while white Seis look pants!

 

[craigb244]

yeh white sei look poo.

took the car for a blast down the lanes today. its sooo much nicer to drive the power output is so smooth that you can really get on the throttle without fear of boost sending you into a fence/ditch.

its got a bad miss fire at above 80% throttle and on boost that is not nice. tired to sort it but nothing seems to help. its a strange one. if i take it easy it wont miss at all all the way to full throttle/boost 100+mph

 

[Munkul]

looks good apart from all those pipes/cables everywhere! Surely you can do a neater job than that

IMHO sounds like a weak spark... could be low dwell but if its same as I had it should be fine... could also be a weak coil or HT lead.

Ive had similar problems and it was a HT lead causing it, and you're still running standards which are pretty wanky. K1 ones are reasonable and have a lifetime guarentee

EDIT: oh you said it makes full boost strange... it isnt the ECU losing sync then? Have you done a lost sync log?

 

[lxfusion]

Those rear wheels are looking badass!

 

[craigb244]

:O bugger off! Id like to see someone do a better 16vt with oil cooler/remote filter with less and neater hose work! lol

after I posted on here i did think that maybe the dwell is a bit low (not changed it since the 8v with the two single coils) the coil stays cool so might crank it a little and see... could be the HT leads also i guess.

No its not losing sync or restarting. I run hall sensors on both cam and crank and the signal is perfect.

 

[craigb244]

Those rear wheels are looking badass!

haha cheers... need to get new tyres for the fronts.

 

[craigb244]

been taking the car down the lanes and racked up about 150 or so miles and the engine is really bedding in well.
ive been using auto tune on a really low setting so its very slowly building it a map up.

the miss fire is almost gone now and i can see on the map exactly where is was

going really really well atm... no real teething troubles either:slayer: