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cally turbo boost settings

2K views 40 replies 10 participants last post by  Bren 
#1 ·
i've just bought a standard cally turbo. could someone plz tell me what's the highest boost i could run without ****ing up the car??
thanx......
 
#28 ·
Surely its the same principal as computer CPUs...

CPU Manufacturers build in a certain level of tolerance into CPUs to allow for fluctuations, differing build quality, overclocking, etc. Most CPU manufacturers also make CPUs using the same core throughout a range - an Intel Pentium 733 has exactly the same core as a Pentium 1Ghz, for example.

I guess what Im saying is like CPUs (and clutches) manufacturers build in a certain level of tolerance that ensures they have very small numbers of returned faulty items. Upping your boost to insane levels probably wouldn't damage the engine in the short term, but would almost certainly reduce its life expentancy - much like CPUs.
 
#29 ·
Durzel said:
Upping your boost to insane levels probably wouldn't damage the engine in the short term, but would almost certainly reduce its life expentancy - much like CPUs.
Yes it would - it would melt the pistons in seconds.
Try running 20psi with a standard engine setup (just screw the actuator rod all the way and disconnect the Amal valve, or disconnect the actuator pipe altogether)

If you let the turbo push more air in the engine, you have to match it with extra fuel, and cool it down to (at least) what it used to be. Even this will push the effective Compression Ratio to beyond 15:1 during full boost. Unwise mate...
 
#30 ·
Can i ask about the pros and cons of fitting a bleed valve is.
i presume these are a simple way of knocking the boost up slightly without overdoing it.
as Dilly's question was all about in the first place, this is also what I would like to do,
1st, buy a bleed valve,
2nd buy a chip (collins chip) ???
3rd, buy a charge cooler.
 
#31 · (Edited)
Pros -

Easy way to up the boost as it fools the ECU into thinking it is runnin gless boost than actual so doesnt cut it back as normal


Cons -

The ECU has no real control ovcer the boost so the bleed valve/owner is under control which can be risky.

The spring on the bleed valve can fail causing the engine run unlimited boost and then blowing up.



If your going to buy a chip then get a Phase I/II and do the boost control properly rather than using a risky bleed valve.
 
#32 ·
i pulled both the little pipes off the valve yesterday and was shocked at the power i got,
until the cut out came in and i nearly hit the windscreen with me noggin..
thought a bleed valve would be a cheep power compromise for the boost setting.
 
#33 · (Edited)
Bren said:
Can i ask about the pros and cons of fitting a bleed valve is.
i presume these are a simple way of knocking the boost up slightly without overdoing it.
'Slightly' is the key word here. If you're gonna run a couple of extra PSIs on max boost, that wouldn't really hurt, as the fuelling would be within the manufacturer's safe limits.

But it's very-very easy to go overboard and effectively cripple the actuator. That would leave you with lean mixture under boost and excessive charge temps. Not a nice combo.

First things first: a front-mounted intercooler is the way to go. It can reduce inlet temps down to 20-30C above ambient. 130C can become 60C, which your engine will appreciate massively.

Then you can look into improving fueling and chipping.

That's the way to go, not the other way round.

I used to run 22psi with the stock intercooler, and the power increase was miserable - inversely proportional to the risk of blowing up. The charge temps can reach 200C with the stock turbo producing 22psi in the summer. Not healthy.
 
#34 ·
Thanks John,
I do have a Astra MK3 though, and am not sure if The front mounted intercoolers will fit my car,
which is why I was thinking of a charge cooler,
I don't know much about these, will I still be struggling for space with one, and will it benefit my engine as much as the intercooler would?
Is there much difference in price between a charge cooler and an intercooler?
 
#35 ·
Depends on location.

A front mounted intercooler thats average size will pip the chargecooler once you are moving.

A chargecooler has the advantage of cooling the charge even f stopped for a small period (traffic lights etc) whereas intercoolers dont.

If you can fit an intercooler then get it... if not then chargecoolers can achieve around 15-20 extra BHP and 20 lb/ft on an average day (mine made 16 extra)
 
#36 ·
Richie said:
Depends on location.

A chargecooler has the advantage of cooling the charge even f stopped for a small period (traffic lights etc) whereas intercoolers dont.

If you can fit an intercooler then get it... if not then chargecoolers can achieve around 15-20 extra BHP and 20 lb/ft on an average day (mine made 16 extra)
Actually there's not much need for cooling the charge while you're stopped and idling.
But the chargecooler will get heatsoak in these conditions, while a properly placed i/c won't.

If it's absolutely impossible to properly fit an intercooler, then a chargecooler with a big water tank is the next best thing.

Why don't you consider a standard intercooler (which is smaller) mounted at the front. It should give similar results to a chargecooler, without the heatsoak.
I'm talking about the standard chargecoolers sold by Courtenay and Regal. I suspect there may be better designs around with proper rads, heat exchangers and tanks.
 
#37 ·
If I should use a front mounted intercooler, does the standard one still get used or can it be taken away for extra space.
also, should i get a smaller radiator from a smaller engined car so there is enough space to run the intercooler pipes around the front, or will this not be addequate..
 
#38 ·
Bren said:
If I should use a front mounted intercooler, does the standard one still get used or can it be taken away for extra space.
If you use a super-duper front mounted i/c (IF it fits in front of everything!) then the stock one should go. It's not just the extra space, it's also that the pressure drop it creates won't be justified by the temp drop it will create in the new setup. It will be more of a liability.

also, should i get a smaller radiator from a smaller engined car so there is enough space to run the intercooler pipes around the front, or will this not be addequate..
NO! If anything, you should go for a Bigger water rad, not smaller. I went for a SuperCore rad, which is a direct replacement of the stock unit, but with larger core holding about 0.5lt of extra coolant.

Remember, that the i/c should be placed in the direct airflow, in front of anything else. And the plumbing should be as straight as possible. No sharp turns.

If you have a space problem, try fitting the stock i/c up front. It will make a big difference.
 
#40 ·
Tommy G said:
i've heard of some sort of bolt on kit from germany that ups your power to 300bhp-ish - know any details? Would that sort of thing be a set of big intercooler, chip, accumulator or what?
It's the PhaseIII kit.

Gavin at walaceperformance.co.uk imports them.

It's a kit of chips, FPR, spark plugs and intercooler. Does what it says on the tin (but your turbo won't live too long doing these kinds of boosts)
 
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