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ZS Phil 06-08-19 10:02 PM

Quote:

Originally Posted by p_b82 (Post 379771)
Yeah - it was a case of "do we continue to persevere with these issues, or just take that step back and generate our own signal" ... we've done the latter, and things are looking up.

I'll hopefully have some figures of it on SDI's and then the custom injectors - as you say clean burn is more critical with VNT, so hopefully we get some good figures that don't require de-coking every 200 miles :D
the comparison of the curves will be interesting, I've always been worried that bigger units is pushing boost/torque too high up the range for every-day driving.

I use google photos; you can share the direct link in img tags if you open the "long link" by viewing the image itself.
Others I think use one of the apps that enables photos to be attached using that, but I can't comment on it.

Thanks for the tip regarding the photos, had a play and think I've managed to link one picture... the most important one!
You're right regarding bigger units pushing the curve to the right but I suppose when the power does come on its more linear than a smaller unit which can give almost a bell shaped curve as it runs out of puff higher up. Swings and roundabouts I guess.
Cant wait to try some different injectors. Got some new nozzles in the garage to try, just need to get them set up with raised opening pressures. If you still want yours testing (you mentioned it a few years ago) Id be happy to, although I guess you're not far off testing them yourself from the sounds of things!
https://lh3.googleusercontent.com/Q6...g=w493-h657-no

p_b82 07-08-19 08:20 AM

You're still over stock peak torque at 2400 rpm - but given that you've only got a 1200 rpm band of peak torque/power by the look of it, it makes that sweet spot smallish.

That said, if you're not giving it full beans you're not going to notice that in real world with the extra torque that you do have on tap. so looks good :)

We're looking at peak torque around the 2k mark - inline with the crappy stage 2's; with the aim to hold it flat until 4k (might not be possible but that's the aim), maybe 4200.. but unfortunately our head design just doesn't make sense to tune it up to the 5500 limit as you can see it just runs out of puff.

RE the offer of testing, I think at this point we're close ourselves so I'll pass; I'm happy that they flow enough fuel as I fitted them previously, the issue will be what the combustion is like...

There are more nozzles that can be tried in the catalogue than there were a couple of years back, so if they don't work, I may well fire these ones your way (not having the soot aspect to content with) if we end up doing some trial and error. If you're interested in experimenting that is.

ZS Phil 26-08-19 08:13 AM

Always up for a bit of trial and error so just keep me posted. Last week I dropped off some spare injectors and new bigger nozzles to a local specialist to rebuild/ balance and most importantly play with the opening pressures. We'll then see what happens.
Regarding the graph I can see what you mean from how it looks but actually (and I agree it's a very personal/subjective thing this), having come from naturally aspirated petrol engines which all like to be thrashed to make progress (cammed v6 race car, v8 ZTT and recently added vx220), I actually like the linear power curve. There is something satisfying about building the revs and the more you work it the more power you get. My hardcut is set to kick in between 4800 and 4900 but you can see from the graph there is still over 190bhp at the limiter. Also, the fact that power and torque gradually build puts less stress on the drive train.
That said, a huge lump of low down torque does make the car feel "muscular" and with a vnt, assuming it can be properly controlled, I guess you can hopefully make it cling on to the top end too and have best of both worlds.
My 330d always felt like that, a low down hit but still pulled and pulled up to the top.
Hopefully you'll make it to POL or similar at some point as I'd love to see how they drive differently.

p_b82 27-08-19 09:25 AM

Tbh - I think the aim is to be looking at about the same sort of torque peak as you've got, just starting a bit earlier in the range.
Like you, I've got a bit of awareness of mechanical sympathy; but we'll se what the pressures are all looking like as well as smoke/soot levels etc.

venturing into the unknown, but the test bed runs all suggest it'll spool like a 15 and is an 17/18 hybrid so should also give me more up top.

It is not going to pull as hard as the mustang regardless what I do, less torque & fewer revs; but I think it will corner better and be more "real world usable" with the power/torque it will have.

As you say it is all subjective & once it's on the road more than happy to meet up, hoping to make more events when it's allowed on the road again!
Worst case mini meet half way one time!

gAZ 02-10-19 08:02 PM

Quote:

Originally Posted by ZS Phil (Post 379754)
It's been 4 years since I updated this thread!
Upon our return from the road trip in 2015 I thought there were a few "niggles" to sort with the car. A proper strip down revealed a bit more work than that was needed! So much so in fact that the sensible thing to do would have been to scrap it. Being a sentimental old fool, that was never going to happen.
So, after lots and lots of work (which I will try to document with pictures at some point), 4 years later she was back in action.
I've done less than 100 miles in her since the full rebuild but just had to get her on the dyno.

On well used SDI injectors and a "max fuel" map she pulled a healthy 203HP / 373Nm.

Can update the spec list if needed.

:trampoline: 200+ bhp L series?

Wouldn't mind seeing the complete spec list for those mods that got you those gains? + price of parts.

:trampoline:

peterzs 02-10-19 08:35 PM

still loving my derv

158 and 238 but goes like a train.

great cars.

ZS Feels more planted than my 160 TF AND I HAVE NEVER HAD A TWITCHY moment going fast round a bend. Not like the TF where I have to keep my foot down to keep it balanced.

gAZ 06-10-19 07:19 PM

Quote:

Originally Posted by peterzs (Post 379939)
still loving my derv

158 and 238 but goes like a train.

great cars.

ZS Feels more planted than my 160 TF AND I HAVE NEVER HAD A TWITCHY moment going fast round a bend. Not like the TF where I have to keep my foot down to keep it balanced.

I agree.. They do handle exceptionally well for a 15 year old car! :bow:

Although their 'refinement' especially at lower speeds does leave a little to be desired. :horse:

I'd say I love my mk1 ZT190 a lot more overall but when pressing on and taking twistys , the ZS TD feels far more fun and rewarding than the big ZT190 .

As a track car, I bet the ZS is a real hoot to race on track!.. Just wish it felt more like the ZT in all the other areas . :)

peterzs 08-10-19 03:32 PM

:):):)


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