To stroke or not to stroke.....
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- Gio_SA
- South Africa Cordinator
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Hi Zoners
So I am in a little pickle now.... I have been told that my motor has a piston slap and I would need to rebuild the complete motor.
Now I am sitting with the choice to either just redo my motor or stroke it to a 2.9.
Whould you guys agree with stroking or not and if yes, what parts am I going to need to perform this job.
What other advice would you give me with regards to stroking?
I have been informed that I would need a E36 328 crank, standard M20B25 conrods or 138mm conrods and 86mm pistons. As for the pistons I was informed to by forged ones as they do not require any engineering work to be done to them.
Your input will be greatly appreciated.
Laters
So I am in a little pickle now.... I have been told that my motor has a piston slap and I would need to rebuild the complete motor.
Now I am sitting with the choice to either just redo my motor or stroke it to a 2.9.
Whould you guys agree with stroking or not and if yes, what parts am I going to need to perform this job.
What other advice would you give me with regards to stroking?
I have been informed that I would need a E36 328 crank, standard M20B25 conrods or 138mm conrods and 86mm pistons. As for the pistons I was informed to by forged ones as they do not require any engineering work to be done to them.
Your input will be greatly appreciated.
Laters
Gio_SA
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if you can afford it & you want to stroke it all the way to 2.9 then have a look here
http://store.nexternal.com/shared/Store ... =492484688
as from what i've seen it look's like a near complete kit.
http://store.nexternal.com/shared/Store ... =492484688
as from what i've seen it look's like a near complete kit.
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
Gio - its on wiki before you get
by other users - all info re stroking
http://www.e30zone.net/e30zonewiki/inde ... ding_a_2.8
- guys will have various opinions - IMO I would stroke it
Reminded me of a song in fact
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http://www.e30zone.net/e30zonewiki/inde ... ding_a_2.8
- guys will have various opinions - IMO I would stroke it
Reminded me of a song in fact
[youtube][/youtube]

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there is that but at the end of the day you know that your engine has been rebuild with brand new parts & will last you a very long time providing you look after it corectly.Gio_SA wrote:Yo steve_k I've seen that kit and it does cost more than a lot....
mind you i don't know what the exchange rate is between US & SA.
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
- Gio_SA
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True that steve and at a exchange rate of R7.80 to the dollar it does not seem all that bad. Than there is the transportation costs included in this, wonder how much that will work out to?steve_k wrote:there is that but at the end of the day you know that your engine has been rebuild with brand new parts & will last you a very long time providing you look after it corectly.Gio_SA wrote:Yo steve_k I've seen that kit and it does cost more than a lot....
mind you i don't know what the exchange rate is between US & SA.
Gio_SA
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can't help on the transport cost as i have no idea at all.Gio_SA wrote:True that steve and at a exchange rate of R7.80 to the dollar it does not seem all that bad. Than there is the transportation costs included in this, wonder how much that will work out to?steve_k wrote:there is that but at the end of the day you know that your engine has been rebuild with brand new parts & will last you a very long time providing you look after it corectly.Gio_SA wrote:Yo steve_k I've seen that kit and it does cost more than a lot....
mind you i don't know what the exchange rate is between US & SA.
you've got the link to them now so if you decide to go for it then get in touch with them & see what they say.
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
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no worries glad to helpGio_SA wrote:Will do thanks for the assistance steve_k

if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
- Gio_SA
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That's what I have been told as well DanThe.
Anymore inout from any of the other members coz I can use all the help I can get.
Anymore inout from any of the other members coz I can use all the help I can get.
Gio_SA
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Holy mother of god.
They do a 3.1 litre M20????
The prices on that Ireland Engineering site look bargain-tastic..... but are they? I mean the 2.9 kit is just over £1100.
considering it includes a crank AND pistons it looks bloody cheap to me.
They do a 3.1 litre M20????
The prices on that Ireland Engineering site look bargain-tastic..... but are they? I mean the 2.9 kit is just over £1100.
considering it includes a crank AND pistons it looks bloody cheap to me.
- AlpineAde
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MillRat, a new user on here from Australia, has a 2.9 kit from IE. He's very happy with it. He runs it with the Miller MAF and WAR mapping system and is making very good power.
If you want larger than 3.1 litres have a look at Metric Mechanic and the 3.2 litre kits.
If you want larger than 3.1 litres have a look at Metric Mechanic and the 3.2 litre kits.
- AlpineAde
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Don't quote me on it but if I remember correctly it's about 145kW at the wheels, which is around 195rwhp. In terms of brake horsepower I suppose that would amount to somewhere around 245bhp odd (just over 180kW), taking into account drivetrain loss on the dyno. By doing a remap on the WAR chip I know that he gained near enough to 20hp at the wheels, which is a very good result. So, it does a bit better than a standard M50/52.
If you PM him, I'm sure he'd tell you of his experience with his stroker.
If you PM him, I'm sure he'd tell you of his experience with his stroker.
That makes the pricing of a stroker kit tempting.AlpineAde wrote:Don't quote me on it but if I remember correctly it's about 145kW at the wheels, which is around 195rwhp. In terms of brake horsepower I suppose that would amount to somewhere around 245bhp odd (just over 180kW), taking into account drivetrain loss on the dyno. By doing a remap on the WAR chip I know that he gained near enough to 20hp at the wheels, which is a very good result. So, it does a bit better than a standard M50/52.
If you PM him, I'm sure he'd tell you of his experience with his stroker.
The 24v lump will have a better power delivery and be slightly more economical, but on the other side of the coin you'll have a freshly rebuilt motor making around the same power for about the same money.
Hmm, this changes things.....
- AlpineAde
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If I was in the position of looking for an upgrade to a standard M20 I would go for spanking fresh stroker every time. I can't help it it, but I'm always wary of second hand engines ~ it's a personal quirk....
The only exception I would make was if I could get my hands on an S50 that I knew the provenance of 100%.
Mind you, whacking in a 24v with over 190bhp as standard makes a lot of sense in terms of bang for buck. Especially the 2.8, given the torque of the engine.
The only exception I would make was if I could get my hands on an S50 that I knew the provenance of 100%.
Mind you, whacking in a 24v with over 190bhp as standard makes a lot of sense in terms of bang for buck. Especially the 2.8, given the torque of the engine.
- Gio_SA
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Thanks for all your input guys, it's much appreciated.AlpineAde wrote:Don't quote me on it but if I remember correctly it's about 145kW at the wheels, which is around 195rwhp. In terms of brake horsepower I suppose that would amount to somewhere around 245bhp odd (just over 180kW), taking into account drivetrain loss on the dyno. By doing a remap on the WAR chip I know that he gained near enough to 20hp at the wheels, which is a very good result. So, it does a bit better than a standard M50/52.
If you PM him, I'm sure he'd tell you of his experience with his stroker.
Wow, a power figure of 145Kw at the wheels will be what I want from a 2.9 stroker but is it realistic and was the dyno that he used not just over generous????
If the IE 2.9 kit can really produce those power figures (with the extras and a job well done obviously) than that price is dirt cheap in my opinion.
My other option was to just slap a M52B28 motor into the E30 and call it quites coz they just sound so flipping pimping, see link.
Would acceleration like in the link below be possible or what other mods would you require to achieve it?
Gio_SA
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- AlpineAde
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If you really want to go bonkers on a stroker there are guys making a shedload more power than that. Reggid, a member on here, runs a 3.1 stroker and makes 165kW odd at the wheels. A few Aussie guys make quite a bit of power with their strokers. 
As for MillRat, I have no reason to doubt the guy whatsoever ~ he's as honest as the day is long. Top bloke! I'll find his build thread for you if you'd like.

As for MillRat, I have no reason to doubt the guy whatsoever ~ he's as honest as the day is long. Top bloke! I'll find his build thread for you if you'd like.
Last edited by AlpineAde on Thu Feb 18, 2010 6:32 am, edited 1 time in total.
- Gio_SA
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Yo AlpineAde
It's not that I doubt MillRat, it's just that some dyno machines are very generous as you know.
I am not looking to that wild just want to go 2.9 stroker for the biggest.
It's not that I doubt MillRat, it's just that some dyno machines are very generous as you know.
I am not looking to that wild just want to go 2.9 stroker for the biggest.
Gio_SA
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- AlpineAde
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Of course, matey ~ some are very conservative, some are quite generous. My dyno guy, for instance, is known as being incredibly conservative...but the point of dynos is tuning not for "true" indications of power. The only way you'll get that is to take the engine out and put the bugger on an engine dyno. MillRat is an old hand ~ he knows his stuff, so I reckon he's on the money with what he has to say about his build.
As a guide when i made 160+ odd kW at the wheels a 330ci manual (M54B30) with the same stroke crank made 133kw at the wheels a few days earlier on the same machine so much for 24V valvesAlpineAde wrote:If you really want to go bonkers on a stroker there are guys making a shedload more power than that. Reggid, a member on here, runs a 3.1 stroker and makes 165kW odd at the wheels. A few Aussie guys make quite a bit of power with their strokers.
As for MillRat, I have no reason to doubt the guy whatsoever ~ he's as honest as the day is long. Top bloke! I'll find his build thread for you if you'd like.

If you go custom pistons you'd be nuts not to use a bigger crank!
E30 325is with M20B31
GIo - as you are based in South Africa, have you been to see Budler Motorsport, they do all the work on my car and have done 2.8liter kits and 2.9. I would suggest you go 2.7 rather then the larger bores , the E30 motor is known to crack between the cylinder walls when heat goes up. Remember that our temps are a lot higher then the UK , also alititude would mean that the motor needs to be rev happy.
- Gio_SA
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Hi Shaheenk
Noted bru, but there are quite a few guys (espescially on the SA E30 forum) that are running 2.9 strokers and they do not seem to have any gripes at all.
I have not been to Budler as yet but I was also advised to get Tune Tech to do my 2.9 stroker as they will do a better job but who is to say cuz.
Anyway, I'm still in the researsch stages so I'm taking everyones opinions and formulating one perfect plan on what route to take. Someone even suggested I build my stroker myself as I will be putting more care and time and precision into my build..... The only perblem is... I'm not good around egines and still trying to learn.
Noted bru, but there are quite a few guys (espescially on the SA E30 forum) that are running 2.9 strokers and they do not seem to have any gripes at all.
I have not been to Budler as yet but I was also advised to get Tune Tech to do my 2.9 stroker as they will do a better job but who is to say cuz.
Anyway, I'm still in the researsch stages so I'm taking everyones opinions and formulating one perfect plan on what route to take. Someone even suggested I build my stroker myself as I will be putting more care and time and precision into my build..... The only perblem is... I'm not good around egines and still trying to learn.
Gio_SA
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Cool, I know Boetie for years and he has always worked on my crs, I had an incident with Tune Tech a while ago and although it is personal I would not say they are not good tuners.
In the end it's your money dude, just be careful who you spend it with.
IMO you not going to notice a diff between a well tuned 2.5 and a 2.9 at the reef, maybe at the coast yes, but not much at the reef besides the added torque.
In the end it's your money dude, just be careful who you spend it with.
IMO you not going to notice a diff between a well tuned 2.5 and a 2.9 at the reef, maybe at the coast yes, but not much at the reef besides the added torque.
- Gio_SA
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Dude what are you saying.... "IMO you not going to notice a diff between a well tuned 2.5 and a 2.9 at the reef, maybe at the coast yes, but not much at the reef besides the added torque."
Please elaborate on this statement coz there are guys with 2.9's here at reef that would tear a 325is to shreds what more of my 2.5.
Is it not a case of more displacement = more power?
Also is it not forcefed and charged cars that perform better at the coast than at the reef?
Please elaborate on this statement coz there are guys with 2.9's here at reef that would tear a 325is to shreds what more of my 2.5.
Is it not a case of more displacement = more power?
Also is it not forcefed and charged cars that perform better at the coast than at the reef?
Gio_SA
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Nope, NA performs better at the coast, thicker air , more molecule more power. Turbo's loose about 15% NA looses about 25%.
More displacement does mean more power and yes 2.9 would run a 2.7 away , but the 2.7 and 2.5 motors are well built units, remember with displacement comes higher fuel consumption as well. You would need to compesate for that with a chip and maybe larger injectors as well.
If you have the budget to stroke, then I would rather go the multivalve route, the motors are newer and make more power. If you simply have piston slap then you need to check why this is , does the car smoke, does it burn a lot of oil. whats the compression like. Most mechs will always try to get u to open up , put newer things in when not needed.
I have had experience with modd's on a car, you will have teething problems, if this is a daily driver, can you afford to be without wheels for a long amount of time. Added to this the additional stress put on the clutch , drivetrain ect.
Just my personal opinion, if I had to do it over again , I would go E36M3 motor and be done with it. 210kw is more then enough
More displacement does mean more power and yes 2.9 would run a 2.7 away , but the 2.7 and 2.5 motors are well built units, remember with displacement comes higher fuel consumption as well. You would need to compesate for that with a chip and maybe larger injectors as well.
If you have the budget to stroke, then I would rather go the multivalve route, the motors are newer and make more power. If you simply have piston slap then you need to check why this is , does the car smoke, does it burn a lot of oil. whats the compression like. Most mechs will always try to get u to open up , put newer things in when not needed.
I have had experience with modd's on a car, you will have teething problems, if this is a daily driver, can you afford to be without wheels for a long amount of time. Added to this the additional stress put on the clutch , drivetrain ect.
Just my personal opinion, if I had to do it over again , I would go E36M3 motor and be done with it. 210kw is more then enough
- Gio_SA
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The more I research this issue the more I'm leaning to going with the M52B28 motor....
trust me buddy.... if I had the funds fot the E36 M3 motor I would not even be researching a stroker conversion.... 210kw is more than enough and will take me a while to get used to and ugrade the rest of my box to handle to power.
Alas, the search continues....
By the way, my car does not smoke or use alot of oil for that matter... why do you ask... are these symptoms of a piston slap?
trust me buddy.... if I had the funds fot the E36 M3 motor I would not even be researching a stroker conversion.... 210kw is more than enough and will take me a while to get used to and ugrade the rest of my box to handle to power.
Alas, the search continues....
By the way, my car does not smoke or use alot of oil for that matter... why do you ask... are these symptoms of a piston slap?
Gio_SA
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Yes , those are the traditional signs of a motor on the way out , bit of piston slap could be due to rings being worn, hence the piston moves about in the block , does it slap when cold or whn hot.
I would say multivalve or rebuild to stock spec. but thats me.....
I would say multivalve or rebuild to stock spec. but thats me.....
Does anyone else think that people trying to convert people into putting a 24V (or FI) into an E30 over a NA M20 stroker is getting a bit old?
If the OP wants to know whether he should stroke his original engine i fail to see where a 24V engine comes into the equation apart from using the crank from one!
I'd prefer a S50b32, S54B32 or S38B38 the only 24V worth swapping IMO in their donor cars to be honest.
If the OP wants to know whether he should stroke his original engine i fail to see where a 24V engine comes into the equation apart from using the crank from one!
I'd prefer a S50b32, S54B32 or S38B38 the only 24V worth swapping IMO in their donor cars to be honest.
E30 325is with M20B31
- AlpineAde
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To be honest, yes.reggid wrote:Does anyone else think that people trying to convert people into putting a 24V (or FI) into an E30 over a NA M20 stroker is getting a bit old?
Agreed. See my post above. An M engine would be the only one I would consider. Until then I will stick with an M20, 2.5 for now but down the track...strokers makes good sense given certain parameters.reggid wrote:If the OP wants to know whether he should stroke his original engine i fail to see where a 24V engine comes into the equation apart from using the crank from one!
I'd prefer a S50b32, S54B32 or S38B38 the only 24V worth swapping IMO in their donor cars to be honest.
This is nothing against the M50/52 lads, such engines are a nice swap ~ if you want to go that route.