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teen ti
04-02-2012, 08:33 PM
As i just bought another ti, i am faced with the issue that plagues the car. a lack of power. Im only looking to get a moderate power gain out of the engine, say 20-25hp, just to make it a little bit quicker. I figured id chip the engine, get an intake and a cat-back exhaust to start out with, but i would imagine that this would only be good for around 10hp. Then i got thinking would it be reasonable to bore the engine out to say 2.0 or 2.1 L. I know an engine swap is the most efficient way to gain power but I'm weird and would like to keep the M44 engine with the car. So back to my issue, would it be reasonable to bore the engine out a little? And if so what kind of power gains should i expect? Then what else on the car would i need to change to accommodate the new bore? Would i just need new pistons or is there more than that? Ive really got limited experience with the engine itself so I'm just kind of spit-balling here. Any and al ideas, responses or tips are greatly appreciated. thanks

pdxmotorhead
04-02-2012, 10:09 PM
Boring a AL block is a cubic $$ proposition and the M42/M44 block has little room for an overbore.

The only cost effective displacement increase is a stoker crank from a diesel..
(Search on M47 I believe...)

Dave

teen ti
04-02-2012, 10:22 PM
alright, ill look into that, i just figured that increasing the displacement by 100-200cc and having new pistons might give me an extra 10ish hp. I've got a friend who works on a lot of euro cars and has 2 318is's, both with the M42 but he could bore the engine out for me free of charge so i figured i might as well look into it

Jean H.318TI
04-02-2012, 10:33 PM
why dont just go turbo and have more power with a stock motor, ur gonna end up spending about the same money to stroke/bore the engine than just getting the stock motor turboed or DASH

teen ti
04-02-2012, 10:36 PM
I've just heard horror stories about turbos killing the engine, although my same friend did turbo his M42. I'm really not looking for that much of a power gain, up to 175 max

pdxmotorhead
04-02-2012, 11:03 PM
alright, ill look into that, i just figured that increasing the displacement by 100-200cc and having new pistons might give me an extra 10ish hp. I've got a friend who works on a lot of euro cars and has 2 318is's, both with the M42 but he could bore the engine out for me free of charge so i figured i might as well look into it

It costs over 1500 to bore an aluminum block , the cylinders have to be recoated after the bore is done and that's where the big $$ come in. There are only a handful of after market companies inthe world that can do it right, otherwise you have ot install sleeves in the bore, about 200 per hole to do right.

Turbos especially if you rebuilld the engine correctly are stone reliable when done reasonably conservative... IE not running 25 lbs of boost... on 10:1 pistons...

Basically the BMW M4* series engines were engineered to be light, reliable and make as much mileage and HP as they can. Its a ring of comprimises.

Way cheaper to just go to a 6 cyl if power is what youneed.

Dave

teen ti
04-02-2012, 11:06 PM
ok so realistically boring out the engine is not the best idea. so if i got for a low boost turbo, say 8psi? then i imagine id make the hp increase I'm looking for, but what else would i need to do to the engine to accommodate the turbo?

98318ti
04-02-2012, 11:49 PM
Even though the M44 has an alum block there are iron sleeves in the cylinders. You would just have to find out how thick the sleeve is and how much could safely be taken out of it. Here is another thread on the subject. http://forums.bimmerforums.com/forum/archive/index.php?t-311269.html

It might be better to consider some of the other suggestions as building an engine from scratch requires some knowledge or you will just end up spending a lot of time and money for nothing. However, if you are willing to take the time to find out the answers and do it right it can be very rewarding.

teen ti
04-02-2012, 11:55 PM
thanks ill definitely look into that, ideally id like to stay NA and not FI and I'm only looking for the hp to get up around 160-275 so i suppose the most cost effective way of doing this with the M44 is what ill most likely go with

pdxmotorhead
04-03-2012, 12:06 AM
There are several good threads on here about builds, John Boy having a couple of the bigger ones... My bad I could have swore the M44 was Nicasil not sleeved.

AS far as normally aspirated it will limit your ability to exploit the engine and if you drive it on the street it will be technically illegal at least with the EFI you might pass a smog check if you had to with the right tune, with carbs it wont happen.

Look up Metric Motors , youll get an idea of the cost of high performance work on a BMW.... :)

Dave

teen ti
04-03-2012, 12:14 AM
haha if you're referring to metric mechanics engines I'm quite familiar with their prices on BMW engine builds, granted that would be awesome to have one of their engines in a ti. and I'm not really an engine person so I've got no real idea of whats possible to get out of them, I'm much better with suspensions haha. anyways overall would it be more advisable to do a small turbo over boring out the engine?

98318ti
04-03-2012, 12:25 AM
Even if you don't buy a motor from MM, like PDXmotorhead said just look at some of their build specs for their NA motors. This will give you some idea of what it takes to build a more powerful motor. It takes expensive parts and precise machining to build fast engines and if you stay NA more power is usually a trade off in drivability. Thats why a lot of people like forced induction FI because you can have drivability and more power. I like NA motors myself, just because I like simplicity, but like has been stated on the site many times that M44 is pretty well maxed out from the factory. So to make it better you would have to spend some time and money on it. There is nothing like the sound of a nastyNA high performance motor though if you can get it right.

teen ti
04-03-2012, 12:28 AM
for sure, those metric mechanics engines sound AMAZING revving up to the stratosphere.i guess thats why i really like NA, because you can rev them so much, but if a turbo is gonna be easier to do and have more drivability i suppose thats the ideal route to go with, especially since I'm only looking for a relatively low hp gain IMO

spidertri
04-03-2012, 12:45 AM
I always liked this guy's build
http://forums.bimmerforums.com/forum/showthread.php?t=433471

It's an M42 but still pretty awesome and some of the stuff can apply to the M44.

teen ti
04-03-2012, 12:51 AM
wow, thats hugely impressive.

jca
04-03-2012, 04:25 AM
I've just heard horror stories about turbos killing the engine, although my same friend did turbo his M42. I'm really not looking for that much of a power gain, up to 175 max

Boring out aluminum engines kills them, too. Supercharging is your most cost effective bet in my opinion.

teen ti
04-03-2012, 04:33 AM
as much as id love to supercharge it, I'm not really ready to drop the same money i spent on the car for a DASC

RAiMA
04-03-2012, 06:37 AM
as much as id love to supercharge it, I'm not really ready to drop the same money i spent on the car for a DASC

Whatever performance mod you do, it's going to cost you money. Turbocharging will give the best bang for buck, followed by supercharging, then boring out/stroking etc.

6 cylinder engine conversion will be your best option imo. It will give the least greif out of the above options. Then later if you want more power you can always go FI on the 6 :)

xxxJohnBoyxxx
04-03-2012, 01:26 PM
You could run a small nitrous kit for a 50hp gain.

teen ti
04-03-2012, 03:45 PM
as much as i don't want to do an engine swap, i suppose it is the most practical solution and if i could find the engine from a 323, an M25B25 i believe, it shouldn't add too much weight to the front end, should it?

pnosker
04-03-2012, 04:01 PM
The m42/m44 are not very difficult to bore despite what some are saying. I designed and blueprinted (but never finished due to distractions) a motor with S52 pistons. You can bore to S52 piston diameter easily. A 318i guy in south africa both bored and stroked his motor with S52 sized forged pistons and a M47 crank.

I sourced S52 pistons from a blown motor where 1 piston shattered but the other 5 were OK. Then I got the lining bored to fit and there was enough material still to go further if I wanted. I don't have all the specs since this was 3 or 4 years ago and I sold the motor. Essentially, you go up a little over 100 ccs and get around 10-15 hp.

Whether that's worth it is up to you. The full build required pistons ($100 for 5), new rod and main bearings ($200 or so) and boring at a machine shop which was around $300. Of course for this price you have to assemble yourself. Also you want new piston rings.

familytruckster
04-03-2012, 06:17 PM
The M42 and the 2 M44's I have are not aluminum blocks. What cars came with all aluminum 4 cyls? Z3?

I think what the OP needs is a 6 cyl swap. As for forced induction and motor swaps, that really moves you into some hardcore auto-x classes-like CP an XP. With cobra kit cars and other insanely quick and light cars.

teen ti
04-03-2012, 06:22 PM
this is true, but i think I'm going to use my 325ci for auto-x and id really like to use the ti for driving schools

ti cali ed
04-09-2012, 05:18 AM
Just a few weeks ago I started looking for a few fast easy hp mods. I think the car could use another 20hp. In the end I switched fluilds over to sythetics, rear end, oil. Gave it a new set of plug - bought the car used and they may of been origanals. And replaced the O2 sensor. The car feels like it has an extra 10hp over what she had before the tune up. I know this is sad and probably only puts her back to what she had from the factory. The more I drive the car however the more I enjoy it and am really thinking if the M division stoped at 240hp that may be right amount for the car and being as that 6 is a direct fit and used brings less money than what a rebuild will cost it may be the way to go. Yeah the added weight may be a downfall but the car will still be lighter than a factory m3 so should I complain?

spidertri
04-09-2012, 12:20 PM
The bean counters stopped at 240, M division wanted 320.

ti cali ed
04-09-2012, 05:06 PM
I've worked on a lot of car but will admit I'm new to the bmw thing. Is there a modern bmw powerplant making 320 that will just drop in? And what's that do to the handling? My '65 stang likes to brag about having 300hp+ but it does so in a bull in a china shop, smoke and rumbling exshaust fashion.

teen ti
04-09-2012, 05:16 PM
I've worked on a lot of car but will admit I'm new to the bmw thing. Is there a modern bmw powerplant making 320 that will just drop in? And what's that do to the handling? My '65 stang likes to brag about having 300hp+ but it does so in a bull in a china shop, smoke and rumbling exshaust fashion.

if you're looking for 320HP from a newer BMW engine your best bet is the S54 from a E46 M3 or a M coupe/roadster. Thats gonna add a bit of weight to the front of the car so to balance that out you should move the battery to the trunk, get a CF hood etc. anything to balance out the weight that you added. But you should still have good handling. The catch with 300+HP is that you'll most likely need to change the diff, clutch, flywheel and even the driveshaft to handle that kind of power, theres now way a stock ti could handle that much.

POCti
04-14-2012, 11:04 PM
Ya the swap is most cost effective than anything followed by turbo and s/c but i agree the metric mechanics motor are awesome and one option since you do have friend that works on euro cars could look into buy one or two pieces at a time while your still your ti as is till you collect to all then pull it out have friend help put it together or im sure you can find plenty of others that could lend some help drive 325ci till motors finished since you have all parts shouldn't take too long at that point.

Leo_328i
09-09-2012, 02:18 PM
Yes, what on earth M44 engine is alloy block?

I've only ever seen cast iron blocks and cannot find any literature on any M44 engines being cast as an alloy block.

All BMW 4 cylinder engines are cast iron util the European N42/N46 engines were introduced in MY2002 in the E46 Compact.