Full engine rebuild 325i
Moderator: martauto
Well since the head cracked, or warped or did whatever it did to leak coolant into the oil, the car has been off the road. I decided that I would either:
1. -Sell the car and cut my losses, but I couldn't quite bear that.
2. -Fix the head and wait for the next problem to arise.
3. -Follow my mate's advice and do an engine swap at massive expense.
4. -Or completely rebuild the current engine... with forced induction.
I'm swinging towards option 4 simply because the engine swap seems so complicated and expensive. It would be a possibility if I was a mechanic but sadly I'm not. I like the idea of supercharging the standard lump and was looking at the Rotrex option, although that seems on the pricey side at £3k... I'll cross that bridge when I come to it...
So, does anyone have a ballpark figure how much a full rebuild costs? I'll be doing it in about June next year because I'm gonna be overseas for several months and need to plan what I'm gonna do to keep me sane!
Thanks.
Oh yeah, btw, since the coolant leaked into the oil I flushed and K-Sealed the system and changed the oil so there is no water hanging around where it shouldn't be.
1. -Sell the car and cut my losses, but I couldn't quite bear that.
2. -Fix the head and wait for the next problem to arise.
3. -Follow my mate's advice and do an engine swap at massive expense.
4. -Or completely rebuild the current engine... with forced induction.
I'm swinging towards option 4 simply because the engine swap seems so complicated and expensive. It would be a possibility if I was a mechanic but sadly I'm not. I like the idea of supercharging the standard lump and was looking at the Rotrex option, although that seems on the pricey side at £3k... I'll cross that bridge when I come to it...
So, does anyone have a ballpark figure how much a full rebuild costs? I'll be doing it in about June next year because I'm gonna be overseas for several months and need to plan what I'm gonna do to keep me sane!
Thanks.
Oh yeah, btw, since the coolant leaked into the oil I flushed and K-Sealed the system and changed the oil so there is no water hanging around where it shouldn't be.
"I may be drunk, Miss, but in le morning I will be sober and j00 will still be ugly."
Winston Churchill
Winston Churchill
Yeah but what is the total cost for a 24V swap? Surely more than a rebuild with all the labour and extra parts?
"I may be drunk, Miss, but in le morning I will be sober and j00 will still be ugly."
Winston Churchill
Winston Churchill
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oldroydsr4
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IMO for a well built Forced induction set up your looking at 5k
24v is the way to go, you can but a donor fr well under a grand.
24v is the way to go, you can but a donor fr well under a grand.
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march109
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Definstly cheaper than a proper m20 rebuild.bazeebond wrote:Yeah but what is the total cost for a 24V swap? Surely more than a rebuild with all the labour and extra parts?
325i Tech 1 Touring, breaking.
2.5 high comp. M20, 3.64 LSD, Fully undersealed, Spax springs & Bilstein shocks, s/s exhaust, Alpina rep wheels and more.
2.5 high comp. M20, 3.64 LSD, Fully undersealed, Spax springs & Bilstein shocks, s/s exhaust, Alpina rep wheels and more.
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jaistanley
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I personally vote for an engine swap to an M50 from a 525i. A lot cheaper and easier than you might think...

- DieselMeister
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I've long wanted a 24v E30 - most desirable combination of engine and body possible imo. But increasingly I'm thinking that it might be an intolerable flap in terms of engineering bodgery and expense, especially as I don't have the talent or the time to do any of the work for myself. Also because I'd have to go the whole hog and get an S38 or S50 as they are my favourites (good though the M50 / M52 are)
When I think of it like that, I start to feel that a rebuilt M20 doesn't seem such a severe investment - you would have a practically new donk after all (even if it still weighed the earth and ran on coal
). I'm sure it must be possible to get S50 performance or better without spending the earth. And I'd feel less guilty about molesting my sport as well, heh.
I don't wanna spend more than £3500 total on the following:
A reliable 250BHP minimum to last 100k miles.
Limited Slip Diff
Rear arch and valence respray
EBC brake discs, Ferodo DS2500 pads and Goodridge lines.
Is it do-able for that sort of money without being a mechanic? I've got workshop access to do the brakes and LSD with a mate, and I think another mate could sort me out with the respray for £200. But the engine needs to be done properly.
By the way dieselmeister, I agree!
A reliable 250BHP minimum to last 100k miles.
Limited Slip Diff
Rear arch and valence respray
EBC brake discs, Ferodo DS2500 pads and Goodridge lines.
Is it do-able for that sort of money without being a mechanic? I've got workshop access to do the brakes and LSD with a mate, and I think another mate could sort me out with the respray for £200. But the engine needs to be done properly.
By the way dieselmeister, I agree!
"I may be drunk, Miss, but in le morning I will be sober and j00 will still be ugly."
Winston Churchill
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E30BeemerLad
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DieselMeister - as yours is a sport I would possibly sway away from the 24V swap, just for the sake of originality, but on anything non-precious, I think I would be swayed into doing the 24v swap over plundering loads into a full M20 rebuild
Being sensible, the M50 swap will probably see you at about £700+ on the road.
Being sensible, the M50 swap will probably see you at about £700+ on the road.
- DieselMeister
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Beemerlad - agreed on all points
Baz - I'd say for 250bhp, FI is your best route. A M30 might get you there with mods but really to looking at ~190-200bhp for an M50-M52 or stroked M20, or 300bhp for an S38 or S50. The space in between is only really efficiently achievable with FI on either of the Mxx engines I'd have thought/
Last edited by DieselMeister on Sat Oct 18, 2008 3:35 pm, edited 1 time in total.
That's pretty cheap mate, although I would still be swapping one used engine for another used engine, and would be way short of 250BHP minimum.Being sensible, the M50 swap will probably see you at about £700+ on the road.
"I may be drunk, Miss, but in le morning I will be sober and j00 will still be ugly."
Winston Churchill
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E30BeemerLad
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Any of the M power engines are out of the equation due to cost.
For any forced induction you are going to be into the £3K+ region, £3k probably at the lower end depending on what you do/ use. If you want a cheap way then a freshen up of the M20 will probably eat away £1k for all bearings, gaskets & new set of rings etc plus other bits along the way. This is just parts by the way, no labour.
Then you are into either a super ebay cheapo turbo kit and megasquirt and mapping, which will be another £1K +, again parts/ materials only (except mapping). Plus the forgotten horrors and other issues you will come across along the way.
Otherwise the sky is the limit in what you want to spend.
An off the shelf rotrex kit is probably about £2k, plus the fitting an mapping blah blah.
But 250bhp would be achieved cheaper with forced induction than N/A.
For any forced induction you are going to be into the £3K+ region, £3k probably at the lower end depending on what you do/ use. If you want a cheap way then a freshen up of the M20 will probably eat away £1k for all bearings, gaskets & new set of rings etc plus other bits along the way. This is just parts by the way, no labour.
Then you are into either a super ebay cheapo turbo kit and megasquirt and mapping, which will be another £1K +, again parts/ materials only (except mapping). Plus the forgotten horrors and other issues you will come across along the way.
Otherwise the sky is the limit in what you want to spend.
An off the shelf rotrex kit is probably about £2k, plus the fitting an mapping blah blah.
But 250bhp would be achieved cheaper with forced induction than N/A.
- DieselMeister
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Yeah the Sxx engines will cost between 1.5-3k to get hold of the lump and box. The Mxx will be much cheaper for sure. I think a ow pressure FI could get you 250bhp roughly on budget. That said, these sorts of things have a habit of getting complicated (and over-budget) rather quickly ;)
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GrindCulture
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There was a guy on here who had restroked his M20 to 3.1L using an M54B30 crank, 260 odd bhp IIRC, I'll see if I can dig out the thread...
Not in E30s any more 
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E30BeemerLad
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oh yes indeed, the problem with swaps and projects is that you find more to do and more to modify or replace as you go along.
My M50 swap is a perfect example....
Start off with a "i'll just drop this engine in here" approach, then you find yourself needing to change the diff, so you pull that off, then the rear end comes off and new bushes go in, then the brake pipes get replaced, then the front end gets the same treatment, oh and those anti-roll bars look a bit feeble, maybe I'll replace those too oh and I'm having so much chew with the exhaust manifold, should I just plonk a dirty great big turbo on there instead and so on......
My M50 swap is a perfect example....
Start off with a "i'll just drop this engine in here" approach, then you find yourself needing to change the diff, so you pull that off, then the rear end comes off and new bushes go in, then the brake pipes get replaced, then the front end gets the same treatment, oh and those anti-roll bars look a bit feeble, maybe I'll replace those too oh and I'm having so much chew with the exhaust manifold, should I just plonk a dirty great big turbo on there instead and so on......
So, maybe £1500 for recon engine
and £2000 for the Rotrex
Plus mapping and the other bits I need to do. This is looking like £5000!
Too much to spend on this car I think. It's a shame, but whatever way I look at this, it ends with me selling the car for what I can get and buying another car with high performance out of the box.
It's so annoying because I bloody love my E30, the shape, the sound it makes, the rear wheel drive. But £5000 on top of the £2500 I've already spent on mods including H&R Cup Suspension kit, ARB's, shock mounts, fuel tank, M3 bushes, etc, etc is hard to swallow. Especially when taking into consideration the value of the car after this work, although if I did the mods I'd probably keep her forever!
and £2000 for the Rotrex
Plus mapping and the other bits I need to do. This is looking like £5000!
Too much to spend on this car I think. It's a shame, but whatever way I look at this, it ends with me selling the car for what I can get and buying another car with high performance out of the box.
It's so annoying because I bloody love my E30, the shape, the sound it makes, the rear wheel drive. But £5000 on top of the £2500 I've already spent on mods including H&R Cup Suspension kit, ARB's, shock mounts, fuel tank, M3 bushes, etc, etc is hard to swallow. Especially when taking into consideration the value of the car after this work, although if I did the mods I'd probably keep her forever!
"I may be drunk, Miss, but in le morning I will be sober and j00 will still be ugly."
Winston Churchill
Winston Churchill
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GrindCulture
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http://www.e30zone.net/modules.php?name ... ic&t=98365
Maybe a little more done to it than just a bigger crank...
Maybe a little more done to it than just a bigger crank...
Not in E30s any more 
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daimlerman
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As a ballpark fiqure,my 2.7 M20 cost about £1500 in parts and machining bits that I could not DiY. I am currently fitting an M50 into an ex LHD French regestered touring..nothing like adding to the difficulty/expense!! I bought a '95 525i as an engine donor for £350,I expect to be on the road with a refreshed chassis for under £2000,the inital budget was £1500 and I am almost at that with the suspension and exhaust still to sort.I thought about building another 2.7 or a 2.8 for this car,but rejected them on cost grounds,zoners are admiting to spending £3000 to achieve around 200bhp,or about what my s/h M50 gives.I feel that the M50 will give reasonable performance with better fuel economy than a stroked M20.This s/h M50 has run 131,000 miles,so should cover the same again over the next 10 years.See Daimlerman's Folly in the photo gallery for a few picces.. 
Youth is wasted on the young.
- DieselMeister
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Bang for your buck you can't beat the M50, it has to be said. Best combination of power / driveability / costs (to build and to run). Reliable, cheap and effective way to get 24v. They sound pretty good as well 
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daimlerman
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This was just the conclusion that I came to as well. However,I am playing with a touring of no potential value to anyone other than myself,I would perhaps go down the stroker route if I was playing with a genuine sport,just to keep the underbonnet looking 'stock'.DieselMeister wrote:Bang for your buck you can't beat the M50, it has to be said. Best combination of power / driveability / costs (to build and to run). Reliable, cheap and effective way to get 24v. They sound pretty good as well
- DieselMeister
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Absolutely the right attitude imo. I'd really like a 24v E30 but I'd choose a tourer as a base (heck I tried to buy one but Barry beat to it, heh). If I end up refurbishing my admittedly rusty Sport, I would go for a stroked M20 for that factory sleeper appeal.... Just need to price up my options - a loan might not be the best option at the present time 
I sold a 200BHP Rover 620 Ti (2.0 Turbo) for £300 before buying my E30... At the time I was fed up with trying to figure out the power delivery problems associated with the turbo but with hindsight, £500 probably would have sorted the car out completely. The Rover even had an LSD as standard although was wrong wheel drive.
I never imagined I would spend so much money on the BMW although when buying it I got carried away with the sound of the straight six and didn't check the common faults because I didn't know about them. Top tips - Always do your research!
Looking back, I was ripped off... The bloke I bought it from (who is probably on this forum and was a mechanic so would have known the problems), must have thought it was his lucky day.
He never mentioned that the rear shock mounts were buggered and that the fuel tank p*ssed petrol out when over half full, and the fuel lines leaked, and the waterpump leaked, and the centre prop mount was buggered, and the immobiliser caused an intermittent starter problem. I found all that out over the next few days.
If you're reading this Anthony Goodridge from Wednesbury, I hope your cambelt snaps!
The things you learn!
I never imagined I would spend so much money on the BMW although when buying it I got carried away with the sound of the straight six and didn't check the common faults because I didn't know about them. Top tips - Always do your research!
Looking back, I was ripped off... The bloke I bought it from (who is probably on this forum and was a mechanic so would have known the problems), must have thought it was his lucky day.
He never mentioned that the rear shock mounts were buggered and that the fuel tank p*ssed petrol out when over half full, and the fuel lines leaked, and the waterpump leaked, and the centre prop mount was buggered, and the immobiliser caused an intermittent starter problem. I found all that out over the next few days.
If you're reading this Anthony Goodridge from Wednesbury, I hope your cambelt snaps!
The things you learn!
"I may be drunk, Miss, but in le morning I will be sober and j00 will still be ugly."
Winston Churchill
Winston Churchill


