how much power turbo or n/a m20?
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- john-rambo
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how much power is every1 getting from a turbo'd325 m20 and what boost also how much power is affordably possible from a n/a 325
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Turbo-Brown
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I've got 270bhp on 7psi 
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Turbo-Brown
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Was quite a lot more than I was expecting to be honest! I was aiming for around 240bhp when I started out (foolish me!)thats got to be good for only 7psi.ive got to run 17 psi to get my power figure ,and more boost usually means more expensive rebuilds
However, my power figure for the boost is undoubtedly helped by having 6 throttles instead of 1, massive overkill in the flow area of the intercoolers (I've got two 2wd-cossie ICs running in parallel), the tubular manifolds and then the straight through twin 2" exhaust system which all add up to give a nice easy breathing system
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fuzzy
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never thought about 2 intercoolers before.atm ive got 1 cossie 2wd cooler above the radiator and as space is tight i could try fitting a second underneath the rad behind the slots in the tech 2 kitTurbo-Brown wrote: massive overkill in the flow area of the intercoolers (I've got two 2wd-cossie ICs running in parallel),
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Turbo-Brown
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Should improve cooling of the charge air as it's in the ICs for longer, and it also provides a lower restriction to flow than just the one IC.
That said, those massive Volvo ICs Ant, Fozzy and Toby are using can't provide much of a restriction and certainly fit an awful lot better than mine!
That said, those massive Volvo ICs Ant, Fozzy and Toby are using can't provide much of a restriction and certainly fit an awful lot better than mine!
I've not fitted the volvo one, mines a Pulsar GTI-R with custom end tanks, much smaller than the volvo one, infact a 1/4 of the size! In terms of volume it's 1/3 of the volvo one...... fits nice thoTurbo-Brown wrote: That said, those massive Volvo ICs Ant, Fozzy and Toby are using can't provide much of a restriction and certainly fit an awful lot better than mine!
HI
For N/A engines some of the Khumo cars have been dyoned at 250BHP, my 2.7 makes around about that but as I am about to do an efi conversion i hope to get it dynoed and confirm the figure. The hartge e21 323i group 2 cars made 310hp but that was a full race engine.
Jason
For N/A engines some of the Khumo cars have been dyoned at 250BHP, my 2.7 makes around about that but as I am about to do an efi conversion i hope to get it dynoed and confirm the figure. The hartge e21 323i group 2 cars made 310hp but that was a full race engine.
Jason
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Turbo-Brown
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Any idea on the spec of the 250bhp N/A Khumo cars Jason? Must be a nightmare at low revs?
How you getting along with your TBs by the way dude?
How you getting along with your TBs by the way dude?
http://i56.photobucket.com/albums/g196/ ... 45_IMG.jpg
This engine is in a friends E30 tarmac rally car. Its based on a 2.7 crank, M52 2.8 rods and custom forged pistons. Ported head, Schrick cam (can't remember which- quite tame though) Motec ECU, Jenvey throttles, carbon trumpets and airbox etc etc. It makes 262bhp, and 220 lbs ft at the flywheel. It is very drivable, very flat torque curve from 3000 to 7000 rpm(really!) BUT it was not cheap. It would have been cheaper to buy and S50B32 than build this. Shows what can be done though.
This engine is in a friends E30 tarmac rally car. Its based on a 2.7 crank, M52 2.8 rods and custom forged pistons. Ported head, Schrick cam (can't remember which- quite tame though) Motec ECU, Jenvey throttles, carbon trumpets and airbox etc etc. It makes 262bhp, and 220 lbs ft at the flywheel. It is very drivable, very flat torque curve from 3000 to 7000 rpm(really!) BUT it was not cheap. It would have been cheaper to buy and S50B32 than build this. Shows what can be done though.
- john-rambo
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im only 21 and am not a millionaire guys how much is realistic to spend doin a turbo conversion? will it make much difference 2 a n/a 2.5 if i just add a chip full stainless system including a manifold induction kit and a ported and polished head what sorta gains woult this give me
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Turbo-Brown
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The cost depends on how much you can do yourself really.
Spent about Ԛ£4500 doing mine, but I did loads of stuff that was icing on the cake and not strictly necessary, although it has probably added to the final result.
Think your insurance would be the bigger problem at your age though dude
Spent about Ԛ£4500 doing mine, but I did loads of stuff that was icing on the cake and not strictly necessary, although it has probably added to the final result.
Think your insurance would be the bigger problem at your age though dude
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fuzzy
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mine was silly money really.between 4-5 thousand without the cost of the engine or any parts.would cost nearer 8-9g all in .
definately insurance problems at your age.i pay Ԛ£900 a year and im 36
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Turbo-Brown
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I paid Ԛ£750 for the priviledge of doing 5000 miles per year last October at the ripe old age of 25.
Dread to think what it'd cost for a 21 year old, although having said that when I started work on the GT6, I was only 20 odd, and I based by decision to fit an S50B32 to it on an affordable insurance quote that I had.
6 years and over Ԛ£10K later....it's still no where near finished
Dread to think what it'd cost for a 21 year old, although having said that when I started work on the GT6, I was only 20 odd, and I based by decision to fit an S50B32 to it on an affordable insurance quote that I had.
6 years and over Ԛ£10K later....it's still no where near finished
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Morat
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So come on guys, what power are you getting from turbo conversions?
Turbo-Brown is getting 270 (on a pre-facelift engine?)
But what are the Ant type conversions capable of?
Turbo-Brown is getting 270 (on a pre-facelift engine?)
But what are the Ant type conversions capable of?
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Turbo-Brown
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Surely is! High compression early engine 
Well over 300bhp @ 1 bar, well over, felt more like 400 on the arse dyno!Morat wrote:So come on guys, what power are you getting from turbo conversions?
Turbo-Brown is getting 270 (on a pre-facelift engine?)
But what are the Ant type conversions capable of?
Late engine, low comp, 12.9 head bolts, external gate, big turbo and Msns-e!
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Morat
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Now thats what I want to hear 
What turbo are you using and how long do you reckon the engine will run in that state of tune before popping something?
Also, what turbo are you using?
Sorry to bug you but I'm starting to feel that this conversion is inevitable
What turbo are you using and how long do you reckon the engine will run in that state of tune before popping something?
Also, what turbo are you using?
Sorry to bug you but I'm starting to feel that this conversion is inevitable
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Turbo is a Holset H1C, 82mm compressor, 67mm exducer, more commonly found on 5.9ltr cummins diesel engines although mine is much larger than most, well the turbo is anywayMorat wrote:Now thats what I want to hear
What turbo are you using and how long do you reckon the engine will run in that state of tune before popping something?
Also, what turbo are you using?
Sorry to bug you but I'm starting to feel that this conversion is inevitable
I have no idea how long she'll stay together but stock bolts, HG etc won't hold a bar for long, I'm hopeing for around 6 months per lump if all goes to plan, just enough time to build up another in preperation.
Go big or go home!
HTH, Mark.
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Morat
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you'd rather build a new one than get stronger bolts and a stronger HG? Or is a bar way too much for the stock engine internals anyway?
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Sorry, I didn't explain myself very wellMorat wrote:you'd rather build a new one than get stronger bolts and a stronger HG? Or is a bar way too much for the stock engine internals anyway?
I have fitted uprated bolts already, infact I can supply them too now
Head gasket wise is people's own preference, I prefer to have that weak link in the system as a fail safe, so I have stock HG only, 12.9 head bolts should increase the life and potential but I'd rather that go than a piston or the water channels.
What I meant was stock engine is limited to say 10/12psi realistically, anymore and you will need to spend some more Ԛ£Ã”šÃ‚£Ãƒ”šÃ‚£Ãƒ”šÃ‚£
I did run 15/18 psi on my last garret T3 and it held up ok to a weekends worth of abuse but having then raised it too 20/22psi with the Holset it only lasted 30 mins! and boy was it mullered!
Hope that helps, Mark.
- john-rambo
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the last time i crashed an old car they diddnt even look at it they told me over the fone it was a write off so if i turbod a 2.5 i wouldnt say fuck all id just tell them about the 2.5 conversion and besides insurance assesors are thick as fuck trust me i speak to them all the time. oh and by the way ill be knocking on for 25 when i ve finnished got to have a faster car than me mates astra gte powered opel ascona thats probably gonna have about 170 brake when finnished
tec 2 man saying NO to chrome bumper and tec 1 wrongness!!!!!!!!!
- john-rambo
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also i have done a search on what manifold is best to use for the turbo conversion and it is inconclusive can i use a 325 tds manifold and turbo does it need to be e30 or will e36 bits work
tec 2 man saying NO to chrome bumper and tec 1 wrongness!!!!!!!!!
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Turbo-Brown
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What you choose to do regarding insurance is your business, but please don't encourage others to break the law by not properly insuring themselves.so if i turbod a 2.5 i wouldnt say fuck all id just tell them about the 2.5 conversion
Last edited by Turbo-Brown on Mon Sep 25, 2006 8:19 pm, edited 1 time in total.
How restrictive are they and how big can a turbo be ? What turbo will fit in there with 325tds (e36) manifold.fozzymonster wrote:If you want a decent manifold speak to Ant, he's got contacts for them now
TD manifolds are restrictive and limit turbo size.
I'm not an engine man, but even i know that it's not the size of the turbo you have bolted into your engine bay that counts. I read too many of these threads where people want to have the biggest turbo, but it's all a complete waste if your engine cant handle the turbo. People tend not to want to actually prep their engine, then want to stick massive turbo's on them and then wonder why the car sits in the garage most of the time
Forced induction when done proper is excellent, but like anything in Life, the end result all comes down to the prep at the begining, so if you wanna do it, save money, get the engine low comp'd with any weak internals changed or uprated, then strap your turbo on and you will have reliable power and not be afraid to turn the boost up a notch when needs be 

That's my point. Get the engine prep'd proper and you can stick as big a turbo as you want on. Dont and watch your engine fry everytime you turn the boost up a little 

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E30BeemerLad
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I read something recently in PPC mag that said don't use diesel turbos as they are not designed to take the same heat as a petrol engine so they will effectively melt. Not sure how much truth there is in that statement.
I really fancy some forced induction, but my lookout on matters is may aswell start with an engine designed for it, which is why I keep banging on about surpa turbo lumps, still get 6 pot sound and almost limitless power increases available, depending on wallet.
I really fancy some forced induction, but my lookout on matters is may aswell start with an engine designed for it, which is why I keep banging on about surpa turbo lumps, still get 6 pot sound and almost limitless power increases available, depending on wallet.
You can do that with most engines though Beemer. I think the secret is to have someone in the know how on your side. I hear lots of people having head gasket problems, but i know of a gasket that you can use that would solve this problem. I know it works cause the person i got it from run a high boost turbo E30 for months and never had a problem. There are too many people giving bad advise without knowing what they are talking about, and i know they're trying to help, but all it creats is lots of mis-information, mixed in with the little good advise that the guy's in the know how give out 

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Morat
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What would be very interesting to know is what the vulnerable points are on a standard M20 when thinking of turboing it. The standard 8.8:1 compression is pretty low, and seems to cope with mild boost very well from what we hear on these boards. What I'm trying to work out is how much boost I could reliably run on a standard M20, and what are the bits I should be looking to change first to make it more reliable/capable of bigger boost.
Of course, the extreme boost freaks will just accept that they need to build a new engine every 5k miles or so, but I think that there will be pretty soon be a lack of M20s if we follow that path!
The other way of looking at it is: What do I need to do to make X power?
Personally my goal would be about 350bhp max, with day to day running about 250bhp. To do this it looks like I'd need about one bar of boost. So ideally I'd be looking for the smallest turbo (lowest lag) to produce 1bar up to 6500rpm. Possibly even a variable geometry turbo
To go with one bar it sounds like you're pushing the standard engine pretty hard, so what are we looking at to keep it reliable? Gasket, Bolts, Rods and Pistons? Lower compression as well? I'd rather keep the standard compression with a smaller turbo if required, the temptation with low comp engines is to exploit the extra potential for a larger turbo and build an on/off nightmare that developes 100bhp at 3200 rpm and 500bhp 1/10th of a second later
I realise that I'm all talk on this, and no practical experience with modifiying engines.. but if someone has the patience to explain where I'm wrong I'd be really happy
Of course, the extreme boost freaks will just accept that they need to build a new engine every 5k miles or so, but I think that there will be pretty soon be a lack of M20s if we follow that path!
The other way of looking at it is: What do I need to do to make X power?
Personally my goal would be about 350bhp max, with day to day running about 250bhp. To do this it looks like I'd need about one bar of boost. So ideally I'd be looking for the smallest turbo (lowest lag) to produce 1bar up to 6500rpm. Possibly even a variable geometry turbo
To go with one bar it sounds like you're pushing the standard engine pretty hard, so what are we looking at to keep it reliable? Gasket, Bolts, Rods and Pistons? Lower compression as well? I'd rather keep the standard compression with a smaller turbo if required, the temptation with low comp engines is to exploit the extra potential for a larger turbo and build an on/off nightmare that developes 100bhp at 3200 rpm and 500bhp 1/10th of a second later
I realise that I'm all talk on this, and no practical experience with modifiying engines.. but if someone has the patience to explain where I'm wrong I'd be really happy
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Ant
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OK, in my experience.....
Std bottom end will survive 7-8 psi quite happily with no internal mods, thats using a largish T3 in the 0.67 A/R turbine and 0.60 compressor, this will give max HP of 260 no more than that.
Drop the CR with a thicker gskt, custom pistons, spark eroded stock items or whatever method you choose, use 12.9 grade non stretch headbolts and the bottom end will take 15-21 psi without issue, to get the flow you need a large turbo, Holset HX35, H1C in large trim with smallish ( relative terms here ) 18-16cm/3 turbine housings. this will give power in the 350-400 hp range reliably
For the full monty a welded head ( waterways only ) and M50 con rods and you've got a real strong weapon of an engine there.
the low boost conversion is the most popular, but taking Booty's post as an example, the issue is most people will have the 7 psi conversion done, then temptation sets in and the boost soon creeps above the safe threshold, and that leads to the H/G failure, simply eplacing the H/G like for like is not an answer
In short, to summarise, if you want 250 hp MAX, then a low boost setup is reliable as night following day, but if you want more ( and you will) then the wallet needs to come back out.
All the conversions carried out by A-Tech are future proofed in most respects, the injectors are good for 560 hp on 3 bar, the charge piping and intercooler are specced the same, we use a full standalone ECU with wasted spark as an option, so there is room in the setup to grow.
@ the moment I have 3 turbo conversions in the Workshop, one was to be a low boost, but talking to the client we've realized thats not enough for his needs, one is to be a low comp high boost road burner, the other is a secret for now, as the owner wants nothing disclosed about the spec, fair enough I say.
If anyone wants to come and see me for a Turbo discussion and cuppa, come on down, TN17 2QZ
Std bottom end will survive 7-8 psi quite happily with no internal mods, thats using a largish T3 in the 0.67 A/R turbine and 0.60 compressor, this will give max HP of 260 no more than that.
Drop the CR with a thicker gskt, custom pistons, spark eroded stock items or whatever method you choose, use 12.9 grade non stretch headbolts and the bottom end will take 15-21 psi without issue, to get the flow you need a large turbo, Holset HX35, H1C in large trim with smallish ( relative terms here ) 18-16cm/3 turbine housings. this will give power in the 350-400 hp range reliably
For the full monty a welded head ( waterways only ) and M50 con rods and you've got a real strong weapon of an engine there.
the low boost conversion is the most popular, but taking Booty's post as an example, the issue is most people will have the 7 psi conversion done, then temptation sets in and the boost soon creeps above the safe threshold, and that leads to the H/G failure, simply eplacing the H/G like for like is not an answer
In short, to summarise, if you want 250 hp MAX, then a low boost setup is reliable as night following day, but if you want more ( and you will) then the wallet needs to come back out.
All the conversions carried out by A-Tech are future proofed in most respects, the injectors are good for 560 hp on 3 bar, the charge piping and intercooler are specced the same, we use a full standalone ECU with wasted spark as an option, so there is room in the setup to grow.
@ the moment I have 3 turbo conversions in the Workshop, one was to be a low boost, but talking to the client we've realized thats not enough for his needs, one is to be a low comp high boost road burner, the other is a secret for now, as the owner wants nothing disclosed about the spec, fair enough I say.
If anyone wants to come and see me for a Turbo discussion and cuppa, come on down, TN17 2QZ
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