thinking about putting in a 3.9 liter engine into a 325i i really don't know how much power it would add but i was thinking about adding a turbo and i wanted race grade parts in my engine add so i thought why not get a new engine and i saw a place that could upgrade it to a 3.9 liter and then i could have boost on top of that i know it woul be quick but i want to your opinion on how much power the engine alone would add and i still got to save money becasue it is like 8000 bucks owell it will be fast
all you want to do is make your car have 600-700 hp? Wow, ok here's what you do. First of all you just take everything out of your car. yeah everything. Sell it all. Then you spend about $100,000 unless you want to use Nitrous Oxide to get you there. Basically I don't think that 6-7 hundred horse power is really do able. The engine alone to do that is gonna run you $20 if not more not to mention the huge amount of money to pay some one to install it, unless you feel comfortable doing something like that. I really wouldn't know where to tell you to begin except for start looking into the largest engine that you could fit under the hood for verticle clearance. almost everything else can be removed or moved around a little for horizontal clearence (when your talking about a project of this magnitude). Then also plan to do either a huge turbo, or twin turbo set up. Or just to be special do a supercharged turbo charged set up (yest that is both super and turbo charged and yes it is possible. Toysport has done it). So bascially I hope your a mechanical engineer or have a lot of money and I wish you the best of luck in both reaching your goal and in finding a place to drive the car.
thanks for the input. actually i am thinking about becoming a mechanical enginner. i thougth i would add the 3.9 liter then go with a turbo plus nitrous and otherstuff hopefully i can find a twin turbo setup or i might go with the super/turbo setup that sounds like a good idea i just needd to find a good differential and transmission i would need to do alot of work to save up the cash but iam deffinatlly making this a massive project other then that i will just read more stuff and expirement with diffrent options, what turbo super charger setup would u go with? super and turbo or turbos thaat work sequentially or act as one(two turbos same size and everything) your input would be most helpful ghead
if you do supercharger and turbo charger then they do act together in a way. I've always been fascinated with the idea, because in theory it leads to massive acceleration throughout the rpms. THe supercharger (like all superchargers) kicks in early, like around 3k rpms. This isn't a huge increase because something like 40-50% of the horse power that a supercharger makes is lost to friction with the crankshaft, however, just look at the Ford F-150 lightning. Superchargers can make good power and torque. Then the turbo spools up around 4-4.5k rpms, or really when ever you want, however, if your planing of driving it then I would recomend around there. Most of the power comes from the turbo. Basically what this setup does is gets rid of turbo lag with the supercharger, and then extends the hp curve up into the higher rpms. With teh F-150 lightning all the hp is there by like 3,450 rpms or some ungodly low number like that, so there is no point taking the car above that. However, with this setup it gives you back the rest of your engine potential. Other problems, are how to make the engine handle all of the boost. Finding a rear end that can support those kinda numbers, finding a damn good LSD and a transmission that is geared properly to take advantage of the setup.
i found a preety good place it is called metric mechanic they do all that kind of stuff but i am a hands on guy and would kinda want to do it myself. i really like the supercharger idea or i was thinking a smallturbo then a bigger one but the supercharger would probbly give me a bigger gain in the low end
First off whered you come up with the numbers 3.9 liter? Why not just make it the 4 liter 5 series engine. You want 500 hp? Just run some 8.5:1 compression pistons that are forged. Forged rods and crank as well. Then get some new valves with all the retainers and goodies. A high degree cam. Then push 10 psi through it.
__________________ <span style='font-family:Geneva'><span style='font-size:14pt;line-height:100%'><span style='color:red'>Fox</span></span> <span style='color:gray'>the Pirate</span>
Diplomacy is saying "nice doggy" until you find a rock.</span>
I live my life one quarter mile at a time, and for those 23 or more seconds I'm free.
I'm not sure where you are located but if you are in the US and you wanted cheap HP you could get a LT1 350 V8 from a 90's Camaro or Firebird etc. and then Supercharge it. Even stock you would get much better performance. I would never put an American engine in a BMW but you could get 700hp pretty cheap that way compared to a BMW engine or even a Japanese engine. I don't know how easy it would be to fit that up in a beemer or if the 6speed transmission would fit but it is a commonly used engine for other conversions/hybrids.
my god, my father's stock car has 800 or so HP... A STOCK CAR... It was Richard Petty's and was used in real nascar races for god's sake!
You do NOT NEED THAT MUCH POWER!!!! If the gear ratio was right, he could go 400 MPH with the same acceleration as my car does 0-120. With 800 horses, you WILL spin the tires in first gear if you donít ride the clutch like a granny.
Although, I would love to see what the engine would do to an auto tranny if you ran that much torque though it
(if anyone wants pics I'll post in the pic forum)
If you can handle the power, then by all means, go for it. I'm not stopping you it's just my opinion
I was thinking of a street-car daily driver when I wrote previous post. Racecar, well you need that power
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