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Well, I have a s38b36 that I just pulled out of a totalled M5. I want to rebuild it so I can swap it into another car, but I am in the military and seriously dont make near as much as I should to afford this car. I have access to some great mechanics and a full shop, but flat out Im basically a new guy to auto mechanics and I want to rebuild this myself. I havent started to go into the engine yet, but it ran well before the accident, and still turned over after the accident. I have about 4k tops that I could spend to rebuild this 123K mile engine. My priority will be to build for reliability, but some extra power will be great since im doing this much anyways. My budget is pretty small, but if theres nothing wrong It seems like the rebuild for all seals and gaskets is only about 6-700 dollars.
So assuming nothing is wrong, Im thinkin getting the throttle bodies bored out to 53-54mm, ($600), port and polish the intake manifold, (I really have no idea), chip ($300), im kinda hesitant about getting the cams because I usually only drive this (fast) on the highways, and $1500 seems like a lot for just cams. Headwork would be nice, but 1k for new valves seems like a lot too, plus machining. This is going to end up being a daily driver, but I can adjust for the torque curve. Again reliability is the priority, more power is the bonus.

Comment all you want to.... Please!!!!!!

Unless you have no experiance with this, and want to tell me that a rebuild costs 10k.
 

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i'm relatively new to the S38, but i have a couple of thoughts. 123k is not a lot of milage assuming the engine was maintained well. Do a compression and leakdown test if you can to see where you stand. Since the engine is out, i'd consider a 'top end rebuild' which you might be able to swing for your budget. Valve job, clean up the ports, new gaskets, maybe a fresh oil pump, timing chain tensioner (maybe a new chain). Bottom end should be good for 200k assuming good oil changed regularly.
The euro 3.8L engine used larger throttle bodies, so maybe you could source those used, but honestly, without cam and major port work, not sure if you'll gain anything. There really isn't much of an intake manifold to port/polish, can't really do that to the plenum, just make sure the resonance flap works. Could do cam gears if you want to move the power band down a bit.
 

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Hi, was the engine running ok before the smash? 123k is not alot of mileage for one of these engines - I wouldn't rebuild it if I didn't have to.
If you do everything you can to get it running as it should, you will have a reliable 300+bhp engine that will do another 50-70k miles at least.
Save yourself a few bucks.
 

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Agree entirely with the above two posts - the engine is in a good state of tune from the factory, so I'd get it working as it should and leave it at that.

If you still want to spend some money, buy the best brake pads and tyres you can afford and spend the rest on renewing suspension bushes, etc - a sharper handling car will be more satisfying than a more powerful one that has a soggy chassis :cool2:
 

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Unless you have no experiance with this, and want to tell me that a rebuild costs 10k.
Forgive me, but I don;t really understand what you mean by this.

A good rebuild carried out by a good mechanic DOES cost 10k when the engine is in bad shape and in need of new parts. There have been people who tried doing it for less, but they haven't enjoyed it for a long time.

Sure, if someone would rebuild it by themselves it would save labour cost. But you have to ask yourself if you should do this if you are asking these questions

No offense.
 

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Forgive me, but I don;t really understand what you mean by this.

A good rebuild carried out by a good mechanic DOES cost 10k when the engine is in bad shape and in need of new parts. There have been people who tried doing it for less, but they haven't enjoyed it for a long time.

Sure, if someone would rebuild it by themselves it would save labour cost. But you have to ask yourself if you should do this if you are asking these questions

No offense.

None taken. I have some very experianced mechanics who are basically working in the shop and are more than happy to help but this particular engine is just new to us. If the rebuild is going to cost me more than 5k, I will end up selling it wherever I leave off, so I basically cant let it come down to that, and im way too stubborn not to try.

I guess I should have stated the condition better first. Yes it was running great. It was dynoed a few months before and got the correct numbers that everyone else seems to get I think it was 273hp and 243 ft lbs, not sure If I can get a hold of their sheet.
Their was some oil on one of the spark plugs, and this car was involved in a front end accident. the harmonic balancer was ruined, and the airbox was destroyed, but the rest of the engine looks fine on the outside. It turned over fine afterwards, (forced to do it that way).
These do seem to go another 50k, but id rather rebuild it with nothing wrong, and close than that. I already have had a new waterpump, timing chain mod, and oil pump waiting for the rebuild on my engine before I got hold of this one.

Oh and sad part, the tires and brakes were just recently replaced, but getting cut off by a drunk driver didnt help.
 

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None taken. I have some very experianced mechanics who are basically working in the shop and are more than happy to help but this particular engine is just new to us. If the rebuild is going to cost me more than 5k, I will end up selling it wherever I leave off, so I basically cant let it come down to that, and im way too stubborn not to try.

I guess I should have stated the condition better first. Yes it was running great. It was dynoed a few months before and got the correct numbers that everyone else seems to get I think it was 273hp and 243 ft lbs, not sure If I can get a hold of their sheet.
Their was some oil on one of the spark plugs, and this car was involved in a front end accident. the harmonic balancer was ruined, and the airbox was destroyed, but the rest of the engine looks fine on the outside. It turned over fine afterwards, (forced to do it that way).
These do seem to go another 50k, but id rather rebuild it with nothing wrong, and close than that. I already have had a new waterpump, timing chain mod, and oil pump waiting for the rebuild on my engine before I got hold of this one.

Oh and sad part, the tires and brakes were just recently replaced, but getting cut off by a drunk driver didnt help.

In that case, here goes....
Top off: you dont need new valves, polishing the old ones will do if no burnt ones. Replace valve stem guides and seals, Camgears/sprockets timing chain/tensioner guides. If you want to, you can polish ports etc but not really necessary.
Inspect/measure damage/wear in cylinders while the top is of if Ok, do nothing.
Replace big end bearings and rod bearings, measure/balance the cranc (this is important as there might have been impact to the cranckshaft....)
Change oilpump. and all the gaskets/hoses possible.

Parts will set you back about 2500-3000 usd....(if original....)

Search for VespaM5: s thread about the complete overhaul he did byhimself, more clues for what to do and costs state side. He did the pistons as well....

Search also for the BMW: s own workshop manual with all the correct torque values etc in it(1100pages), it has also been linked to here on the forum.

Good luck
:cheers:
Sakke

PS: Any halfassed mods will not do a damn thing for the performance, if there is no funds to mod thoroughly(ie. in a way that gives increased power) I would go purely for a solid rebuild.....
 
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