Author Topic: help me decide!!!! (Read 10352 times)

nickmpower · « **on:** August 09, 2006, 01:17:11 PM »

Im having a very hard time deciding what i should do with my engine rebuild. I'll decide what i want then it will change the next day. Maybe you guys can help me figure it out? The 2 main options im thinking of are

s52 pistons with turbo. this is what ive been thinking about for the last couple days but now my mind might be changing again. I dont know how much boost a RRFPR can be used up to? otherwise, it seems like such a hassle with megasquirt ect. for tuning.

m44 crank with s52 pistons modified for 10:1 or a little less compression. I was goign to do this, then backed out, but now im leanig back towards it again. I figure if im not happy with that i could find a cheap dasc as there is another supercharger coming out that some e36 guys will upgrade to. This seems like the easiest, most hassle free, also the most reliable as the dasc has a bypass valve so its under little or no boost at part throttle. I could even set it up to be able to turn it on and off. its also a very well tested setup.

deciding which college i wanted to go to was 10x easier then this, so please help me!!!!

dino245 · « **Reply #1 on:** August 09, 2006, 02:14:05 PM »

Nickpower, I went through this same dilema and settled on the NA 2.0l engine. This is the S52 pistons and M44 crank. 2002maniac and I are building identicle motors. I went so far as to buy a supercharger and larger injectors as well as a 4 bar fuel pressure ragualtor. I settled on the NA combination to keep it drivable and dependable. There will always be some car faster then mine and I am ok with that. This car is a blast to drive with 134hp, and at 175hp it will be crazy fun to drive. I would focus on learning how to drive the most from the car and tires for the track days.

Febi Guibo · « **Reply #2 on:** August 09, 2006, 03:53:00 PM »

I think the big issue is where you want the power... I didn't really care about the low end (eg, below 5000 rpms) and when I drive for fun, I keep the water boiling so to speak.

But, if you want a bigger, flatter torque curve, it's tough to beat the supercharger... having said that, you can rebuild for N/A w/high compression, and then later, with some minor mods (eg, even a thicker headgasket) supercharge it.

D. Clay · « **Reply #3 on:** August 09, 2006, 06:27:44 PM »

This is a little off topic, but what is the max power from the later model production M42's.
Also, what is the "quick and dirty" low cost HP upgrade (less than$1K) worth in terms of HP?

silverblades181 · « **Reply #4 on:** August 09, 2006, 09:48:16 PM »

the power of the later M42 is 138 hp and M44 is 140 hp I believe.

The only worthy low cost upgrade that I know of is the MarkD chip.

asubimmer · « **Reply #5 on:** August 09, 2006, 09:54:21 PM »

I say s52 pistons and boost but then I'm a little bias

w/ a turbo you can change things easily, ie diff turbos, to lower lag or increase power. And who doesn't like boost lol

nickmpower · « **Reply #6 on:** August 12, 2006, 12:14:19 PM »

well instead of getting my current pistons machined and new rings ect. Im going to look into some custom ones because i think it may be more cost effective and they will be better and new. what is the biggest bore size you guys would run with forced induction? Im not sure i will, but i want to leave the door open u know? im thinking 86.5 would be good and on the safe side?

Febi Guibo · « **Reply #7 on:** August 12, 2006, 09:08:57 PM »

88mm is prolly the biggest you can go for an N/A motor at around 11.6 compression... so, maybe someone here with an engineering background can do some quick math... what's yer target boost?

nickmpower · « **Reply #8 on:** August 12, 2006, 11:11:10 PM »

like 7-10 i think, if any ever. but if i get custom pistons, im wondering if i might as well just get the 88mm crank! how much did those non interference pistons run u febi?

nickmpower · « **Reply #9 on:** August 13, 2006, 05:38:24 PM »

on the web site they list pistons for the m10 (dont have the m42 listed) as around 800, and a crank kit for around 1200, are these around your costs febi?

nickmpower · « **Reply #10 on:** August 22, 2006, 04:42:15 PM »

I just called MM

88mm crank $1100 (including bearigns)
rods $780 (including bearings)
pistons $900 (WITH RINGS)

idk if i am going to do it or not. it wouldnt be so bad with out the rods but thats what the pistons are made for

Euro Nation · « **Reply #11 on:** August 22, 2006, 05:34:53 PM »

I want you to do some more shopping... and this time stay away from MM.

You can damn near get a set of EIGHT full custom S60 pistons from Wiseco for $900. A set of four custom pistons will run you around $600 with rings and pins. At $780 for rods I hope they're Pauters... because you can buy Pauter rods for that much.

I've never been a fan of expanding stroke anyway... especially when you consider that the gains found from the increased displacement hardly warrant the cost of the crankshaft itself, let alone the other parts or things like camshafts which are required to get a true gain out of your new girth.

This is why forced induction is usually the best option for engines with weak aftermarket support. I really really don't want to step on any toes here but I still haven't heard any rave reviews of peoples 2.1L engines. While no one is talking them down I think it may be because they're embarrased at the hp-gain/$$$ ratio they had at the end of the project.

tim_s · « **Reply #12 on:** August 22, 2006, 05:55:15 PM »

Quote from: Euro Nation

I want you to do some more shopping... and this time stay away from MM.

You can damn near get a set of EIGHT full custom S60 pistons from Wiseco for $900. A set of four custom pistons will run you around $600 with rings and pins. At $780 for rods I hope they're Pauters... because you can buy Pauter rods for that much.

I've never been a fan of expanding stroke anyway... especially when you consider that the gains found from the increased displacement hardly warrant the cost of the crankshaft itself, let alone the other parts or things like camshafts which are required to get a true gain out of your new girth.

This is why forced induction is usually the best option for engines with weak aftermarket support. I really really don't want to step on any toes here but I still haven't heard any rave reviews of peoples 2.1L engines. While no one is talking them down I think it may be because they're embarrased at the hp-gain/$$$ ratio they had at the end of the project.

I see where you're coming from - if I went for a turbo, i wouldn't bother messing with the stroke, wouldn't do too much with the bore either, would get some nice 86mm low CR pistons and go. i also just about agree that bang for buck turbo is the probably best bet if you stick with standard internals, but if you factor in a proper rebuild and do the turbo thing right, it will cost more.

having said that, quite contrary to the not hearing rave reviews of 2.1 conversions, I'm absolutely chuffed with mine. It's jsut what i was looking for, but then again i was always realistic about what I would gain and also knew exactly what I wanted. I wanted a rebuild for reliability and performance. A turbo wouldn't have helped me for reliability and would have affected my fuel economy pretty badly, which I didn't want as I do loads of motorway miles.
The car is way faster with the 2.1 in it, I've driven a 1.8 since and been surprised how slow I thought it felt. Where it was the same performance as my bro's M44 e36 before in a straight line, now in 3rd gr alone from low rpm I can pull out from behind him and overtake - that's a huge difference in performance. With the ITBs etc I'm really so happy with the car. Sure I've spent a lot of money, but its very fast, totally reliable and an absolute pleasure to drive, it will also last for a long long time, as its now basically a new engine, not a 15+ yr old one. In short, if I could make the decision again, I'd def do it this way again, as if I'd gone turbo i'd have spent more and probably been less happy with the finished result in terms of reliability, fuel consumption etc.

nickmpower · « **Reply #13 on:** August 22, 2006, 06:09:11 PM »

yeah I want mine to run like stock (only faster!) and not have to deal with tuning and detonation and all that stuff. I think an FPR and some big injectors should do me fine for the increased displacement? I think febi is just running injectors. I'll probalbly want around 10:1 compression, that way if i ever get tired of the power output, i can slap on a dasc.

euronation, can you please tell me where you are getting these prices? I see m62 pistons listed for 1399 on vacmotorsports.com

maybe i can jsut order the stuff through my machinest? i dunno, the MM prices dont seem THAT bad.

Febi Guibo · « **Reply #14 on:** August 22, 2006, 07:02:54 PM »

For my driving style and overall goals 2.1L was the way to go... there are pros and cons, and it's not for everybody, but the bottom line is that I have a nearly zero-mile motor that will run well at high revs and make great power for a long, long time.

...that, and a lifetime warranty.