I'll get right to the point. Mathematically speaking, a naturally aspriated Ecotec swap into a 1988 Fiero 4 cylinder coupe with a 5-speed manual, and a battery relocation to the front gives you a weight of 2497 lbs and a weight distribution of 49.15% in the front and 50.85% in the rear, or basically 49/51. Near perfect!

I rechecked my math that I did after weighing my Ecotec (310lbs) before installing it, then weighing my Duke (360lbs) after ripping it out, then weighing my battery (30lbs). Here's my math:

If I remember right, the stock weight distribution is 47% Forward / 53% Rear. With 2547 lbs stock, that's 1197.09 lbs in front, and 1349.91 lbs in the rear. Subtract 80 lbs from the rear, and add 30 lbs to the front, then we have 1227.09 lbs in front, and 1269.91 lbs in the rear. So really, my initial estimate of a 1% shift to the front was wrong. A naturally aspriated Ecotec swap into a 1988 Fiero 4 cylinder coupe with a manual transmission will net a weight distribution of 49.15% in the front and 50.85% in the rear, or a 49/51 front/rear weight distribution. When I get it in running condition, I'll try to get scales under it.

And yes, I know alot of people are all like "Oooh, now you can't kick out the rear end in a turn and drift it." I don't want to do that. I want the car to stick, not drift. I would have gotten a Nissan S15 if I wanted to drift.
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So... let the bashing and nay-saying begin! lol!

Actually, I'm sure I messed up a number or two somewhere in this.

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Petty Officer Michael C Casaceli
Aircraft Electronics Technician Second Class
AIMD Brunswick (2007-present)
Patrol Squadron Ten (2003-2007)
United States Navy

Don't forget about your lightweight flywheel. I'm assuming that will account for another 15 lbs (approx.) out of the rear of the car.

Just out of curiousity, what diameter exhaust are you planning on running?

i really think a turbo or supercharged 2.0 ecotec would be a very cool setup. make the car lighter and still make great power. be a killer auto x and track car for sure.

An NA Ecotec could use exhaust piping with a similar diameter to the duke for sure, but with my turbo setup, it's going to be 3" until it goes to the muffler, where it splits in two 2.5" pipes.

And you are correct about the lighter flywheel, but from what I've seen, alot of people who upgrade the clutch on an Ecotec usually get a lighter flywheel. To my knowledge, the stock Duke is the lightest available, so I feel it's a fair comparison. Plus my piston/rod combo is heavier than stock, so that adds some weight.

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Petty Officer Michael C Casaceli
Aircraft Electronics Technician Second Class
AIMD Brunswick (2007-present)
Patrol Squadron Ten (2003-2007)
United States Navy

[This message has been edited by fieroturbo (edited 01-13-2008).]

Does your 310 Lbs comes from the entire engine + "all" the turbo related items? (Intercooler, turbine, housing; oversized exhaust and piping, etc.)

The turbo items alone could weight as much as 100 Lbs by them selves. That is why I did the N* swap. Because by the time you set up a turbo car with all the needed gadgets you might as well go with a light weight NA engine and enjoy the lag less driving, not to even mention the headaches that come with any turbo car. I know that you might argue this, but I've had many turbo cars, and no it’s not my luck.

JG

I was under the impression that the stock weight balance was 46 / 54. But in any case, you're taking a big step in the right direction.

Check your initial estimate for weight distribution.

Conjecture only gets you so far... just go weigh the thing.

Lighter is always better, but weight distribution really isn't the holy grail of handling. I'd rather keep the battery in the rear to keep its contribution to the vehcile's MOI small than move it up front to "improve" weight distribution.

you can do some easy weight trimming in the back and get that to 50/50 pretty esily since your already so close. when you do get it running and at a car scale, I would do multiple measurements... one with driver and full tank of gas, one with driver with an empty tank, one without driver and empty tank, another without driver and full tank, etc. so you can trim excess weight to fulfill your desired weight transfer, if done right you might be able to get real close to 25 / 25 / 25 / 25 to the wheels. there is a lot of weight to be removed from fieros.

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1987 Pontiac Fiero GT
418ci 'Mini-Rat' motor
dual stage nitrous injected
built 5-speed getrag

[This message has been edited by RichLo (edited 01-13-2008).]

[QUOTE]Originally posted by fieroturbo:
I'll get right to the point. Mathematically speaking, a naturally aspriated Ecotec swap into a 1988 Fiero 4 cylinder coupe with a 5-speed manual, and a battery relocation to the front gives you a weight of 2497 lbs and a weight distribution of 49.15% in the front and 50.85% in the rear, or basically 49/51. Near perfect!
[QUOTE]

50/50 Would not be "perfect" if the car is intended to do serious Road Course Racing, see snip it below for attached link:

"The rearward weight bias preferred by sports and racing cars results from handling effects during the transition from straight-ahead to cornering. During corner entry the front tires, in addition to generating part of the lateral force required to accelerate the car's center of mass into the turn, also generate a torque about the car's vertical axis that starts the car rotating into the turn. However, the lateral force being generated by the rear tires is acting in the opposite torsional sense, trying to rotate the car out of the turn. For this reason, a car with "50/50" weight distribution will understeer on initial corner entry. To avoid this problem, sports and racing cars often have a more rearward weight distribution. In the case of pure racing cars, this is typically between "45/55" and "40/60." This gives the front tires an advantage in overcoming the car's moment of inertia (yaw angular inertia), thus reducing corner-entry understeer.

http://en.wikipedia.org/wik...#Weight_distribution

A whole lot of people, including the author of that article are operating under the implicit assumption that the car carries equal tires at all four corners.

If the chassis engineer does his job, then the car carries equal *contact pressure* front and rear, both static and dynamic. That quote also overlooks what happens when the car *exits* the corner, as well as longitudinal weight transfer. In underlying principle, the article is correct: the front tires need enough excess grip to be able to steer the car into and out of the corner; but the idea really needs to be stated in terms of grip, not weight. A car with 10/90 weight distribution will handle just fine as long as it has motorcycle tires in front and 335's in the rear...

I didn't make my post with any intention of telling him how to setup his car. The point, and why the link was included (which contains other factors, and other links), was to shed a little light that performance handling isn't all about weight distribution.