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Can you ?


Dnk

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you can, how long they last is another question

 

what is the problem with running them at 1.5 bar ? this is one bit of how the turbo works that i dont understand.

 

could you enlighten me, is it down to its internal design size etc

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I wouldn't :eek:

 

EGT's :blink:

 

I think IanC also tested running his hybrid's at 1.4bar v 1.3 and found no gain, it was a while ago so, have a dig around. (It was on Jspec)

 

What would you do for the fuelling to keep AFR's in check ?

 

What is the limit of the MAF ?

 

Changing the hardware and running the same boost 'should' give you more power.

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what is the problem with running them at 1.5 bar ? this is one bit of how the turbo works that i dont understand.

 

could you enlighten me, is it down to its internal design size etc

 

They will be so inefficient they will heat the air up by more than you will get back from the extra boost basically. That's ignoring the fact you would need a way of increasing the fuelling etc etc.

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I dunno how many times it needs saying. Turning the stock turbo's be they JorUKspec much past 1.2 bar is counter productive. If you really want the optimum performance from your stockers take your car to a dyno and set it up there. Start with 1.1 bar and advance the pressure from there. If you have an EGT gauge that would be helpfull and use the dyno's afr meter as well. As the car starts to lean and power increase drops off with accelerated EGT's stop upping the boost. I'll put money that without WI you'll get as far as 1.2 to 1.25bar before it all starts to go pete tong.

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My appologies for asking about something that's been done to death but when Turbo Technics said i could run there stage 1 up to such a high boost i thought i'd ask.

 

I've done search's but get too much info and was a bit swamped so thought i'd ask and hopefully get straight to the answers.

 

Thanks for the input.

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I think IanC also tested running his hybrid's at 1.4bar v 1.3 and found no gain, it was a while ago so, have a dig around. (It was on Jspec)

 

1.4bar was best power, 1.5bar+ was a significant power drop off. They were good hybrids and are still going in their 3rd car now :) Stocker j-specs I wouldn't go past 1.2bar though. UK spec, unknown.

 

The EGTs at 1.4bar were, on a hot summers day doing a top speed run at TOTB, 920degC (measured at #1 exhaust runner very close to the cylinder head). So just under the generally accepted 950degC limit, which means it was safe under worst case scenarios. With good fuelling and intercooler etc etc of course.

 

-Ian

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1.4bar was best power, 1.5bar+ was a significant power drop off. They were good hybrids and are still going in their 3rd car now :) Stocker j-specs I wouldn't go past 1.2bar though. UK spec, unknown.

 

The EGTs at 1.4bar were, on a hot summers day doing a top speed run at TOTB, 920degC (measured at #1 exhaust runner very close to the cylinder head). So just under the generally accepted 950degC limit, which means it was safe under worst case scenarios. With good fuelling and intercooler etc etc of course.-Ian

 

So really to be ultra safe 1.3 bar is a good place to stop on hybrids with the mods that ive already got ?

 

I was thinking when i have the head rebuilt and do the turbo's i'd change the injectors as well, will new o/e ones be up to the job or would it be better going up to say 650's rather than the 550's ?

 

What power did you see at 1.4 bar on the hybrids you mention above and who did them ?

 

Thanks for the info its most helpfull

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What are you going to control the bigger injectors with? Also if you are on the dyno setting up the injectors you can do what I said previously and keep upping the boost until you see the drop off point and have your system set up to its optimum.

PS

My appologies for asking about something that's been done to death but when Turbo Technics said i could run there stage 1 up to such a high boost i thought i'd ask.

 

 

They are going to tell you that as they are selling you the turbo's lol. Perhaps in another system flowing different air etc they can boost to 1.5 bar who knows. Just as a comparison duracell say their batteries last 6 times longer than ordinary batteries but do they and do you believe it lol?

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What are you going to control the bigger injectors with? Also if you are on the dyno setting up the injectors you can do what I said previously and keep upping the boost until you see the drop off point and have your system set up to its optimum.

 

 

Ive no idea and was just thinking outloud, my cars done 120k so thought while im doing the head and turbo's a new set of injectors wouldnt hurt even if im just replacing like for like.

 

Totally agree with a session on a dyno and keep raising the boost gradually to its optimum level.

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They are going to tell you that as they are selling you the turbo's lol. Perhaps in another system flowing different air etc they can boost to 1.5 bar who knows. Just as a comparison duracell say their batteries last 6 times longer than ordinary batteries but do they and do you believe it lol?

 

I was supprised when they said this hence the thread, i dont believe hardly anything anymore, ive asked supposed specialists the same questions and get so many varying answers its becoming difficult to know which way is best.

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Im thinking a back to stock rebuild is possibly the way to go and stick at 1.25 bar which ive been running for a few years now with no problems.

 

I just thought if while im doing all this work would it be worth getting a bit more hp if it can be done safely without having to add more and more mods.

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So really to be ultra safe 1.3 bar is a good place to stop on hybrids with the mods that ive already got ?

 

 

Nah, it'd be rude not to run a good set of hybrids to 1.4bar :D the fact they can run more boost is where they get most of their gains over the stockers.

 

I was thinking when i have the head rebuilt and do the turbo's i'd change the injectors as well, will new o/e ones be up to the job or would it be better going up to say 650's rather than the 550's ?

 

440cc injectors aren't man enough for a good set of hybrids, but the 550cc ones are fine - 650 are overkill unless you want future proofing for a T61 or the cost of the injectors are less than the 550s.

 

What power did you see at 1.4 bar on the hybrids you mention above and who did them ?

 

Thanks for the info its most helpfull

 

They saw 480bhp on a dyno ages ago - how accurate that is I don't know, it's probably a large overread to be honest. However it'd hand a BPU its arse nicely, and would hit over 170mph in 1.25miles from a standing start (TOTB1 and 2).

 

Alas we have no idea where they came from or who did them or what spec they are. The previous owner of the car had them installed and he didn't keep any records.

 

-Ian

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I was supprised when they said this hence the thread, i dont believe hardly anything anymore, ive asked supposed specialists the same questions and get so many varying answers its becoming difficult to know which way is best.

 

Yes, it's difficult. All the stuff I've said is from my experience with my car and hybrids, and I measured stuff as scientifically as I could, and I wasn't trying to sell anything (and aren't now!) :) The bit I trust the least is, ironically, the dyno reading I got :cool:

 

-Ian

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You have 550's already so fuel wise you are good for 450bhp. You will still squeeze the best power available from hybrids with those injectors. Want to tune it a tad higher stick a WI kit on and that'll give you a bit more confidence and latitude to go above 1.25. Without dyno tuning though you are scrabbling in the dark especially if you haven't got an EGT gauge.

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Thanks guys great info.

 

In a nutshell then

 

I shall get the head rebuilt as the stem seals need doing and will have new guides etc,,,get the turbo's hybridised by the best place i can find,,, get an EGT gauge plumbed into the manifold,,,fit new 550's to be on the safe side seeing as there getting on a bit and then off to a dyno.

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Ah but you have "guages" and used timing equipment at the likes of TOTB to prove extra power instead of the old "well it feels faster" line.

 

Ah right :) Good point. Hurrah for gauges :nana:

 

Won't new 550's be an uneccesary expense? Surely its cheaper to have them cleaned and flow tested?

 

Definitely yes. Especially as you have to get the new ones tested and cleaned anyway!

 

-Ian

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