engine and drivetrain Bang For Your Buck Go Faster Mods

[glemon]

Thanks Rocan, I am not sure if I am even getting all the power out of the motor that I should, I have done a bit of fiddling with it, but still need to dial in timing and carb tuning a bit I think, because based on other's descriptions of a stock motor's performance, I am not sure if it is quite "there" yet, so I really should make sure everything on there is up to snuff and adjusted right before I go further, I know just adjusting the valves made it idle much smoother, so there may be some easy gains with minor adjustments to the parts already on the car.

Edited November 20, 2013 by glemon

[ray_]

Only thing raw power is good for is boosting your ego at the stoplights against rice burners and muscle heads. REAL drivers know that "going faster" is all about how fast you can take a corner.

 

I've found the limits of grip on my stock (but fresh) suspension with some generic 185 tires, and it is fast enough to put a lot of newer (heavier) cars to shame. I drive 200-300 miles a week, every single day, all weather, and it's taken me over a year to really find the limits of what a relatively factory stock 02 has to offer. 

 

Ultimately, my point is that if you still haven't fully gotten use of what you have, there is no point spending money to make the car EVEN better than you. 

 

 

You're just jealous.

 

[mike472]

Work your suspension with tires and wheels first, then shocks bars and springs. I chose IE's stage 1 setup with Bilsteins. This is the Best bang for the buck for me when I get a new car. The engine shit is nice but this stuff should come first. Give you engine a good going over as far as timing, points, plugs, wires, etc. Very few modern cars will handle as well as this setup will on a twisty road. If you want a drag racer, by a chebby.

[morfiya]

cough cough im choking(rocan) lol

[Rocan]

Morfiya you get a free pass on that one because you're car is much more then just an m20 swap

[eurotrash]

Save your money on on a track day and hit a good karting track.  Not consumer grade go-karts, but fast (non-shifter) karts that has a rookie class before they turn you loose.  You will learn tons about carrying your momentum, rather than relying on brute force to make you faster.  Many racers use this as a 'poor man's' training facility.  Other than the characteristics of your specific car, you will learn tons, and get to implement the concepts of braking, acceleration and driving line, that will directly transfer to the road and make you, in effect, faster.

 

..and specifically for the car, like others mentioned, add a 38/38 carb. Maybe eliminate the mechanical fan..? Get a good ignition system (crane xr700) and hot coil for today's lame gas (which, I still need to do).  Put a quality tune on the thing.  That's about all you can do with out really tearing the motor down.

Edited November 20, 2013 by eurotrash

[Harv]

I am not sure if I am even getting all the power out of the motor that I should, I have done a bit of fiddling with it, but still need to dial in timing and carb tuning a bit I think,

Well said. And here is your starting point. Make everything work as it should first. Not long ago I bought an old 912. It was running well enough but I knew there was more. Over the last year I have replaced every calibrated part of the Webbers, distributer, airfilters etc. the car now goes like stink and I'm sure the last owner wouldn't recognize the driving experience.

Maybe start with a wide band 02 setup to get the tune exactly right.

[Dev02]

Maybe start with a wide band 02 setup to get the tune exactly right.

 

+100, also check that you aren't losing power somewhere before beafing up the engine.

 

Since no one else has said it I thought I'd bring up that it is power-to-WEIGHT, so if you can't afford to add power maybe look for ways to lose weight?

[FB73tii]

Since no one else has said it I thought I'd bring up that it is power-to-WEIGHT, so if you can't afford to add power maybe look for ways to lose weight?

 

Bingo! Taking weight out not only helps the car accelerate quicker, it lets it stop (decelerate) quicker, too. Unfortunately, to keep all the amenities of a street car it generally costs money to loose weight. We had a thread on this a few years back with lots of good suggestions including lighter seats, fiberglass body parts, lighter engine parts (S14 starter) etc. You can make a spreadsheet to see how power-to-weight changes and what the equivalent "HP increase" is that you can gain from loosing weight. In some cases you may see it is cheaper to loose weight than to upgrade the engine. Also, the lighter a car gets, the more impact dropping the marginal pound makes. E.g., a 1 lb drop from a 2000 lb car is a greater percentage drop than a 1 lb drop from a 2500 lb car. 

 

For example, let's say your car weighs 2500 lb and has 100 HP. The weight-to-power ratio is 25 lb/HP. If you took 100 lb out of the car the weight-to-power ratio would be 24 lb/HP. That is the same weight-to-power ratio you would have if your car still weighed 2500 lb, but you increased engine output to 104.17HP. The question then is which is cheaper to achieve the same effect, removing 100 lb or adding 4.17 HP to the engine.

For comparison, a BMW Z8 weighs 3494 lb and has 400 HP, for a weight-to-power ratio of 8.7. A highly modified M10 engine with 230 HP in a 2000 lb race car will have roughly the same weight-to-power as the Z8.

 

Also, taking out rotating mass (wheels, tires, brake rotors), unsprung weight, and weight above the roll center is a good thing for performance and handling. Now I am not suggesting taking out a hole saw and cheese-holing your rear subframe and trailing arms (I have seen that done on a race car), but this route is something to consider. On my track car I strive to get every gram of weight out that I can.

 

--Fred '69 & '74tii (about 2000 lbs/each with full cages)

Edited November 20, 2013 by FB73tii

[harry6422]

Enjoy your 2002 for what it is and don't wast your money trying to make it something it is not, if you want a fast BMW take the money you save and buy a 90's M3 or a 98-2000 M roadster like mine, then you will have a 3.2 M motor, M brakes and M suspension good for 160mph and 0-60  in 5.2.   The best of both BMW worlds classic and fast.

[eurotrash]

big bumpers are worth 70lbs.  fyi

[FB73tii]

Enjoy your 2002 for what it is and don't wast your money trying to make it something it is not

 

Hmmm...I wish someone told me that 20 years ago. And here I was planning to invest in a JATO for my 2002 --Fred

[ray_]

I almost posted this :-)

 

But then, making an '02 just a bit more sprightly is a laudable pursuit.

 

 

Enjoy your 2002 for what it is and don't wast your money trying to make it something it is not, if you want a fast BMW take the money you save and buy a 90's M3 or a 98-2000 M roadster like mine, then you will have a 3.2 M motor, M brakes and M suspension good for 160mph and 0-60  in 5.2.   The best of both BMW worlds classic and fast.

 

Cheers,

[jrkoupe]

some good answers here..

 

20-25 hp is quite a bit...and not cheap to obtain...lol

 

if ur on a budget....consider a ltw fly..itll change your driving experience...engine will spool up quicker, and give u a sense of speed and nice engine revability....then add a nice exhaUST.... again to change your driving experience.

 

edit..I c you have an exhaust...

 

I can understand folks saying save your money and do a TRACK DAY....iM A TRACK JUNKIE/INsTRUCTOR myself... ETC ETC BLAH BLAH..

 

but honestly, just because u want more power doesnt mean you want to track the car, so thats unfair to you. You want more zip..more uuumph..I get it.

Edited November 20, 2013 by jrkoupe

[GoFaSSter]

Bingo! Taking weight out not only helps the car accelerate quicker, it lets it stop (decelerate) quicker, too. Unfortunately, to keep all the amenities of a street car it generally costs money to loose weight. We had a thread on this a few years back with lots of good suggestions including lighter seats, fiberglass body parts, lighter engine parts (S14 starter) etc. You can make a spreadsheet to see how power-to-weight changes and what the equivalent "HP increase" is that you can gain from loosing weight. In some cases you may see it is cheaper to loose weight than to upgrade the engine. Also, the lighter a car gets, the more impact dropping the marginal pound makes. E.g., a 1 lb drop from a 2000 lb car is a greater percentage drop than a 1 lb drop from a 2500 lb car. 

 

For example, let's say your car weighs 2500 lb and has 100 HP. The weight-to-power ratio is 25 lb/HP. If you took 100 lb out of the car the weight-to-power ratio would be 24 lb/HP. That is the same weight-to-power ratio you would have if your car still weighed 2500 lb, but you increased engine output to 104.17HP. The question then is which is cheaper to achieve the same effect, removing 100 lb or adding 4.17 HP to the engine.

For comparison, a BMW Z8 weighs 3494 lb and has 400 HP, for a weight-to-power ratio of 8.7. A highly modified M10 engine with 230 HP in a 2000 lb race car will have roughly the same weight-to-power as the Z8.

 

Also, taking out rotating mass (wheels, tires, brake rotors), unsprung weight, and weight above the roll center is a good thing for performance and handling. Now I am not suggesting taking out a hole saw and cheese-holing your rear subframe and trailing arms (I have seen that done on a race car), but this route is something to consider. On my track car I strive to get every gram of weight out that I can.

 

--Fred '69 & '74tii (about 2000 lbs/each with full cages)

I remember back in my muscle car/drag racing days.  There were guys that spent a ton of maney and time shaving the engine black and getting out every gram of weight.  You would look at the guys who did this, and drove the car, and they were anywhere from 100-250 lbs overweight.  I always thought that was odd...