Turbo Buffs in here please :)

Malt_Vinegar

Malt_Vinegar

Malt_Vinegar

Don
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Hello knowledgable turbo peeps!

I have a few questions as i now own my first Turbo fitted vehicle. Its a volvo 480turbo. It has a 1.7 renault based engine with a T2 turbo.

These engines were very conservatively tuned as standard and are well capable of a lot more boost than the standard 7.5(iirc) PSI. I know i can adjust this by fitting a boost valve. I have it on good authority that these engines are fine up to 14psi.

I have been made aware of a bloke who will adjust my car for 80 quid. He does a full service using the standard boost controller to make it gradually increase boost through the revs to get up to about 14psi.

Is it worth doing this, or spending a smaller amount on a manual boost controller and attempting to use that to up boost (using the standard boost guage to measure increases)

Also, people have been mentioning adjusting the actuator, and i really have no idea of the benefits, or exactly how to do this? Anyone able to shed some light on the matter?
 
I'm not an expert on that particular engine but when I had my old R5 GT turbo I increased the boost to 18PSI and it made a HUGE amount of difference.

On that particular car you could either fit a bleed valve/grainger valve or adjust the actuator in order to increase the boost. The former is the easiest and costs about £17 however you will have to inform your insurance company and they'll naturally increase your premium.

The latter is more difficult but still only takes about 15 mins to do. Basically you're adjusting the threaded arm on the actuator so that it requires more boost to open. It's completely invisible so it's up to you whether you inform your insurance company or not.

Either way, it's definitely best to get a proper calibrated boost gauge as the standard fit one would probably be fairly inaccurate, not what you want when increasing boost!

It's worth checking whether the standard intercooler is up to the pressure increase though, the R5 one needed strapping to stop the plastic end caps blowing off. Also check that the fuelling will be ok, I don't know anything about that particular ECU so I can't help there I'm afraid.
 
I am told the standard intercooler is easily up to it, its larger than many of the uprated ones fitted to R5s.

I spose i could just drop a different guage onto the tubing from the standard guage.

So, but adjusting the actuator, i could easily bump up the boost? (oh and which way is to up boost, and which to lower it?)
 
You first want to check what fueling the standard car is mapped up to. You dont want to be running boost above what the car can fuel to, otherwise you will be running lean, which wont be of any benefit to you.

Get yourself a manual boost controller, then you can adjust it as you like. Something like this. but make sure you get a boost gauge first!
 
Malt_Vinegar said:
I am told the standard intercooler is easily up to it, its larger than many of the uprated ones fitted to R5s.

I spose i could just drop a different guage onto the tubing from the standard guage.

So, but adjusting the actuator, i could easily bump up the boost? (oh and which way is to up boost, and which to lower it?)
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Definitely get a boost gauge before you do anything, without one you run the risk of blowing your engine (seen it done many times on R5's).

If the actuator has plenty of thread on it then yes you can easily bump up the boost. I don't know the specifics of that particular one but if it's like the R5 one then you can adjust right up to about 18PSI, some actuators don't have much adjustment at all though (like the RS turbo if I recall correctly).

I was going to give you instructions on how to adjust the rod but I just found this article which saves me the effort :)

http://www.saab9000.com/procedures/exhaust/baseboostadj.html (bottom of the page)
 
IIRC the 480 lump will take up to about 13-14psi of boost before you hit problems. Any more than that and the ECU overboost detection kicks in and stops your fun. A friend had one in his Clio, but had it converted to carb so he could run higher boost.

They're not that strong an engine - be very careful upping the boost, they don't like it really.
 
i wouldnt up it to near its limit, if its 7.5 already, then 10-11 would suffice. you dont want to blow the engine on your run around that you need.
 
Trickle said:
He could buy 2 more Volvos for the amount that will cost him ;)
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He he, exactly.

Im thinking get the 80 quid mod done. I then have a car that cost me 491quid and yet should do 0-60 in about (perhaps under) 7 seconds?

Had a look at my actuator, the thread looked a bit ropey, however, might give that a go to whip up a couple extra PSI. Then revert to standard once the mod is done :D

Oh, and apparently the ECU on the 480 turbo is pretty clever and adjusts fueling depending on Boost levels :) So Underfueling wont be a problem as long as i leave the factory 14psi cutoff in tact, and dont try to go for more than 13ish.

Lots of other 480 owners say they have no problems with 14, but i think 12 would be fine for me, seeing as this is only supposed to be a runabout!
 
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14psi on a 1.7l engine sounds a lot for a T2 Turbo.

Upping the boost to 12psi should see a nice gain though. Mine from 6 to 13psi makes a massive difference.
 
Hey Stonedofmoo,

Your Nissan GTI-R I used to have one and found it nearly impossible to get parts, or get parts that were not stupidly expensive, how you finding that?? but other then that nice car :)


Stelly
 
djbenjo said:
14psi will be rather warm on a T2 imho.
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It's widely accepted that 18PSI is fine on the R5 GT Turbo (it also has a T2). I ran that boost for 7 years and never had a problem. I don't know about the 1.7 engine though but the turbo itself is certainly strong enough to handle it.
 
eidolon said:
It's widely accepted that 18PSI is fine on the R5 GT Turbo (it also has a T2). I ran that boost for 7 years and never had a problem. I don't know about the 1.7 engine though but the turbo itself is certainly strong enough to handle it.
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No question it will be strong enough, it just will be out of its efficiency meaning extra heating of the compressed air, especially on a bigger engine.

The T2 on the Fiesta turbos isn't much good for over 170hp and most t25s are only goof dor 200-220. How much power was your R5 running out of interest?
 
Stelly said:
Hey Stonedofmoo,

Your Nissan GTI-R I used to have one and found it nearly impossible to get parts, or get parts that were not stupidly expensive, how you finding that?? but other then that nice car :)


Stelly
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Sorry to go off topic. Parts are pretty expensive mate, pays to be in the owners club as you pick up all kinds of tips on saving money on parts. Fun car though arent they :)
 
eidolon said:
It's widely accepted that 18PSI is fine on the R5 GT Turbo (it also has a T2). I ran that boost for 7 years and never had a problem. I don't know about the 1.7 engine though but the turbo itself is certainly strong enough to handle it.
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Isnt it the case the smaller the engine, the higher the boost you can run. 18psi in a 1.4 isnt the same 18psi in a larger engine.
 
saitrix said:
So what sort of power will you get the Volvo Malt?
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Im being quoted figures around the 160-170 mark by other people who have had the mod done :)

They are saying 0-60 of just over 6 seconds, so i thinking sub 7 should be possible with the autobox.

I was told that auto boxes can have problems coping with the excess heat created at top boost levels. However, there is an easy fix. Apparently, you just add in a small rad (heater matrix will do) into the coolant feed for the gearbox, and this just makes sure you dont cook the fluid :)
 
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