just bought a T25 will it be ok to use on the vts?

[spencer_cammedvts]

take a look at the pics.

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=140119020700&ssPageName=STRK:MEWA:IT&ih=004

[Toad]

Spencer, what are you up to! lol.

If it were me, I would NOT buy a used turbo, especially from Ebay...

Good luck on the project though. Have you got a thread going?

[bullit]

no it wouldnt

[AXracing]

Its a odd one that and a bit on the small side. Its using the 3 bolt exhaust housing and the offset actuator. The studs even are on the flange. All this will make it quite a bit harder to fit and much harder to get hold of upgrade turbos after. I would avoid it. You can get new turbos for a few hundred pounds if you look about, that would be the better way to go if your planning on turbo charging your car.

[spencer_cammedvts]

what mods would i have to make to the turbo to get it to fit good & proper?

im not really fussed about an upgrade turbo. this should see near on 300bhp if done right. im running just shy of 170bhp at the minute so...

im only looking for about 260 @fly though anyway as you cant really use much more than that. IMO

the downpipe and manifold will be self fabricated so can make that fit.

iv been very carefull when buying my parts and have quizzed people a lot. iv been assured that there is no play anywhere and to be honest it doesnt look all that bad to me. i will be getting it reconned before fitting anyway though.

[AXracing]

You should get a copy of the flow map as I think you will fined the turbo will be spinning its little heart out well before you get to 250bhp. I have a the newer GT series turbo that spool up much faster and hold the power for longer and that’s a GT25 with a 61 compressor and 52 exhaust and that would struggle.

[mallboy]

doesnt look that bad, best to look at it for play first. the turbo will show some increase but i doubt you will get that much of a increase. dont forget when turboìng it, you have to lower the compression and that will lose some bhp for starters. the turbo will increase the torque well but im not sure on the bhp hike. best to as someone like tweeqd or gmc as he would be able to advise you on waht to do for the power you want.

[spencer_cammedvts]

well from what i am told... and correct me if im wrong... when simo was using the t2 it ran out of puff at about 180bhp@wheels. id guess that to be somewhere near 220/230 @ fly al least?

the t25/t28 is a bit more "hardcore" and can produce more power than the t2. i did think about a t3 but after research i found that they would have too much lag

[mallboy]

well from what i am told... and correct me if im wrong... when simo was using the t2 it ran out of puff at about 180bhp@wheels. id guess that to be somewhere near 220/230 @ fly al least?

the t25/t28 is a bit more "hardcore" and can produce more power than the t2. i did think about a t3 but after research i found that they would have too much lag

your right about the t25, they have more power. if your car has good acceleration know, then a t3 might not be that bad aslong as you use a bigger bore exhaust so that the turbo spools up faster. that will probs give you the power increase you want

[bullit]

rsearch before buying comes to mind

[spencer_cammedvts]

tbh i thought you could fit any turbo to any car! as long as it fits under the bonnet and you buy the relevant parts to make it reliable e.g. forged pistons, uprated clutch & diff etc...

what different types of turbo unit are they?

[mallboy]

loads, the prism 300bhp saxo on ebay has used a turbo from a vw golf.you can put any turbo on in theory but the best bet is to get the right one for the intended purpose!!

[spencer_cammedvts]

its ok its just that i dont see what is different with the turbo i have bought to any other turbo? and if it is different then what is it and what effects will this have on my mission to make my car a beast?

[tweeqd]

finding the correct turbo is quite a difficult job to do corrrectly, you should flow test your head then with them figures you can choose your cams, with the cam figure and flow results you can work out a turbo using compressor maps, then chosse the turbo depending on where you want the power in the rev range.

there are also loads of different T25 turbos, you can mix and match exhaust and inlet housings to suite what you want but you need to know the flow of each setup.

plus the boost you run at is not what will determin the power its the volume of air, a T34 at 30 psi will flow the same volume as a GT28 at 22psi due to the designe of the turbo, the same works with a T2 and T25 the T2 at 14psi will be roughly the same as the T25 at 10psi

you can bolt on any turbo to any engine to to make it work correctly takes time to work out, its taken me monthes of testing and trial to find the correct turbo for my new engine

[AXracing]

what different types of turbo unit are they?

There are different size turbos. Each turbo has a optimum operating range. This varies on the pressure it runs at. These are normally shown in a flowmap.

If you try and run a turbo below its optimum range it will be very lagy, not flow enough air to maintain boost and or simply stall.

If you run it at over its optimum it will over spin, it will radically reduce turbo life, it will produce massive amount of heat, you will use a lot more fuel for the same power output, you will get massive back pressure and ironically your turbo starts to get lagy at high end as well. if your pushing a turbo well past what it can do you will simply not get enough air. But if you get to that point your doing something very wrong.

But don’t mistake all T2s or T3s of being equal. For instance take a T3 off a metro turbo and put it on a VTS and you will see its way to small. Yet you get a T3 of something like a cossie and it will be very lagy. The T refers to a Garrett format basics the turbo is constructed to, that is all.

Then there are different formats of turbos. There are so may I would not know where to start. But needless to say one is not directly interchangeable with another. Some of them are actually quite poor for performance but most of them are for some sort of legacy compatibility.

Also turbos have different operating designs. For instance many can not handle the corrosive gasses of exhaust. Many come with only small waste gates as there never intended to run at high boost.

[spencer_cammedvts]

well im running 708's at the minute and pushing 147bhp@wheels so id say that my head flows fairly well! lol im on standard intake too. where can i get the head flow tested? is it not possible to work out the flow rate from the cams & other mods i have and the power they are making?

(prob just made me sound really thick but hey!)

also does the head have to come off to test the flow rate?

[tweeqd]

also does the head have to come off to test the flow rate?

to do it properly the head needs completly stripping, then needs to go on a flow bench. ive got a mate with one in his garrage, hes well in to his 5 turbos so weve used all his knolage from them to do mine and spec the engine right.
you can just bolt on a turbo and it will work to some degree, and going by previous experiances of other conversions you could use there findings but to do it 100% it will need a full strip and test but this is very labour intencive so unless you can do it yourself then it gets very expencive

[spencer_cammedvts]

well i know my way round the vts angine as i did the conversion from vtr, stripped the engine,fitted my catcams, port & polished my head thenrebuilt the thing and timed it up. iv never paid a garage to do a thing apart from mot's and my remap at chipwizards.

just turbo technology in not really up to date with. im kinda learning as i go though. slowly buying the parts ad reading up on lots of different aspects. im gonna be fitting forged pistons and refurbing the bottom end anyway so may aswell get the head flowed then!