Diesel Turbocharger On Petrol Engine

[Liam1805]

Been looking into this cant find much info and the info i do find is mixed views, some say yes it can be done and some say no it cant be done. They say that they are low rpm boosting but does that really matter and also they mention difference in heat. Looking at maybe doing a conversion on my 8v engine when its all in and running, diesel turbochargers are much cheaper brand new etc plus i have two knocking about one from a frontera and the other from a combo

What are peoples information on this

[nige-p]

its been done a lot in the saab community with people putting large holset diesel turbos on saab 4 cylinder petrol engines the turbo they use is from a dodge ram pickup diesel and is 5.9 litre straight 6 diesel engine

[Liam1805]

Do you know the reason why they use them chargers off the bigger engine, can the frontera 2.5 charger work on the 8v engines

[nige-p]

they use the holsets really for cheapness and they are over engineered and will take up to around 900 degrees and will still provide good spool for there size

cant see why a frontera turbo wouldnt work

[Liam1805]

Sounds pretty good that, i will have a look into the chargers that the frontera use now see what info i get on them, i dont see how it wouldnt work personally either as they are all the same principal

[Gordo]

Turbo's don't care what engine they're on, just that they don't overspeed. Size it correctly and go for it.

The only thing I can think of, off hand, doesn't ally - some don't like operating in a low pressure condition, as when used in draw through applications, as the oil seals aren't designed for it.

[Liam1805]

Just looked it up and they use the GT15 turbo, im not too clued up on them etc not sure how much power is to be had from them or anything. When you mention they dont like operating at low pressure what exactly does that mean as in what are the symptoms etc

[debeerd]

They work well, but like Gordo said, just need to size them correctly.
There is a formula to calculate the size match.
I think you devide the diesel engine capacity by 1.75 to see if it will be big enough.
So a 5.9L turbo should work fine up to roughly a 3.3 liter petrol.

My one friend fitted a turbo from a 2.7 diesel to his 1.8 engine, it spools quick with 0.4 bar boost at 1400 rpm and full boost at 1600rpm.
But it runs out of puff at 4500rpm.
That turbo would maybe work better on a 1.6 engine (ideal maybe 1.4).

That should help you I hope.

[Liam1805]

Yehha, just worked it out to 1.428 so that would mean it is too small for my 1.8 8v engine or could it still work, its good that they spool up quicker im not too worried about running out of puff higher up

[Gordo]

Just looked it up and they use the GT15 turbo, im not too clued up on them etc not sure how much power is to be had from them or anything. When you mention they dont like operating at low pressure what exactly does that mean as in what are the symptoms etc

In a diesel, or blow through installation the impellor (boosting) side is at atmosheric or higher pressure all the time.
With a draw ( or suck) through installation, the turbo is mounted between the carb' or throttle body and so the impellor side seal may be subject to high vacuum (low absolute pressure) when the throttle is closed at high engine speeds. There may also be a problem with the thrust bearings, but can't comment on that.

[Gordo]

If you just want more torque at lower rpm, and aren't concerned about power, it may be a very good application for it.
Would also be good for offroading and high altitude applications, where pure power isn't needed.

[Liam1805]

Yehh i would be happy with just the low down torque to be honest so would be perfect

[Liam1805]

Just a quick question will a 1.7 TD turbocharger work on a 1.8 8v for a conversion ??

[chip]

Just a quick question will a 1.7 TD turbocharger work on a 1.8 8v for a conversion ??

no because it cant flow enough air

if you want a 200bhp petrol engine, look at turbos capable of 200bhp plus, which wont be on a small vauxhall turbo engine

[Liam1805]

no because it cant flow enough air

if you want a 200bhp petrol engine, look at turbos capable of 200bhp plus, which wont be on a small vauxhall turbo engine

I just checked on garretts information pages and it shows the GT15 has a power range upto 150 bhp, so will it technically work upto 150 bhp which is a 35 bhp gain really speaking, im not looking to build a monster just get used to some boost off a budged

[chip]

Fair enough then mate, yes it would work, just bare in mind it will move the torque right down the rev range and will strangle the exhaust at high rpm so it will be all over by about 4Krpm realistically I would expect

And be careful with det when putting boost into a fairly high comp engine at very low rpm

[Liam1805]

Fair enough then mate, yes it would work, just bare in mind it will move the torque right down the rev range and will strangle the exhaust at high rpm so it will be all over by about 4Krpm realistically I would expect

And be careful with det when putting boost into a fairly high comp engine at very low rpm

Yehh i would take that no worries, i dont use much top end anywhere i go so be nice to have the lower down torque, as long as i know it will work i can go and buy one. It is a low compression engine mate it is a 9.2:1 c/r as it is but may use a de-comp plate if needed it to go lower

[Tathan]

Potentially, EGT could be a problem as petrols will see another couple of hundred degrees on diesels and the turbo might not be of suitable material.

[Liam1805]

Potentially, EGT could be a problem as petrols will see another couple of hundred degrees on diesels and the turbo might not be of suitable material.

So it will not work then will it mate, anything that can be done etc to reduce that problem etc

[chip]

might not last as long as on the original diesel, but i cant see them just melting, these things are generally pretty over engineered anyway, but why you dont just use a 50 quid 200sx turbo instead of insisting on having to use a diesel one is confusing me TBH, lol

[Jasovanooo]

plenty of ****ty t25 turbos floating about from old saabs for £50 or less good for 250 or so

[chip]

yeah another good option, cant see the obsession with turbo diesels when petrol turbos are so readily available at that level anyway TBH

[Liam1805]

Mainly for the lower down torque but im not really really into them if i can get a petrol one then all the better, cheapest saab ones i can fine are around £115 mark, aint had a look for the 200sx ones yet shall have a check now

[chip]

post on the uksaabs forum asking for one, you'll get one for less than that im sure.

[Liam1805]

post on the uksaabs forum asking for one, you'll get one for less than that im sure.

Will do now mate thanks for that