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MG MGB GT V8 Factory Originals Technical - retaining stock weight distribution with ford small block
|This may seem like a simple solution but why not add the equal amount of weight to the rear of the car to balance the weight added to the front.If an aluminum head 302 only weighs 80 pound more then the 4 and you add 80 ponds to the back that will be a very small "160 pound"weight penalty when you can get a EASY 300 horsepower from any late model small block ford.|
|>This may seem like a simple solution but why not add the equal amount of weight to |
>the rear of the car to balance the weight added to the front. If an aluminum head
>302 only weighs 80 pound more then the 4 and you add 80 ponds to the back that will
>be a very small "160 pound" weight penalty when you can get a EASY 300 horsepower
>from any late model small block ford.
While that helps even out the weight distribution, it hurts the polar moment
of inertia (about the vertical axis). The closer the mass is concentrated
to the center of a vehicle, the easier it is to change direction. That's why
unlimited race cars tend to be mid-engined. Ballasting rarely helps cornering.
However, sometimes race cars will need ballast to meet a minumum weight rule.
In that case they will add weight down low (to lower the roll moment of inertia)
and near the center to help the polar moment. One area where ballasting can
help is in high speed stability, say in a land speed record attempt. The top
speed a vehicle can attain is not dependent upon mass (weight). For a given
gearing and power, tt's dependent soley on drag, aerodynamic and rolling. If
you have a lift problem at one end of the vehicle at speed, you can add downforce
or add weight. Since downforce adds drag, weight may be the preferred solution.
|Can anyone with a 302 in the car comment on handling? Since were all speculating on how good or how bad the extra weight might be in the front, let me propose this:|
The amount of torque produced by a 302 WILL cause as much oversteer as your right foot wants.
Should we even worry about 80 pounds worth of push at the front?
|what is the exact weight distribution of the mgb with the stock engine.How would the weight distribution with the small block ford compare to other automobiles known for handling?The weight difference seems minor but is it?|
|equal weight distribution is nice but not the holy grail. Look at all the front drivers with up to 70% front weight and handle great. Look at the Porsche with more than half it's weight at the rear and all the polar momentum there like a pendulum and it handles great. Look at the mid engine fiero with its crappy suspension and steering that pushes its way around corners. More weight needs bigger tires and stronger springs. More horsepower needs bigger driving tires. So you end up with big tires front and back but each end for different reasons. If the car pushes (understeer) antiroll in the rear will make the rear looser and the front tighter. Move the weight around and then modify the suspension to compensate. Barry|
|Nice train of thought Barry!|
I will try to see if I can get my car "wheel weighed" before my conversion. I am the ultimate poor man, and will probably be running my 302 bone stock as it was in the muistang it came from at the start. (CAST IRON EVERYTHING) I WILL be going alum as I go, so I hope to be able to provide actuall numbers on what items affect weight/handling etc.. No promises, but I will try to write it all down and share.
|Read Dan Jones posting again. He is giving you the answer to you dilema of weight distribution with the stock Ford. |
The MGB- GT is pretty close to 51 49 Full tank and spare.
Remove your heater, modify firewall and set engine back.
|look at www.zaks.com/mgb/ it's a very iformative site on the v8 conversion and it includes a the weight of his car at each corner.The distribution is 50.9 front/49.1 rear,using these figures as a base,adding 80 pounds to the front end weight you have 53.5 front/46.5 rear so again i wonder if you would notice in real world conditons such as street tires,etc.|
I don't know what model you have, but here are some numbers that I can vouch for with a c.i. Buick V6
Stock c.b.GT: 2401Lbs; 1162fr/1239rr
My 71 GT V6: 2380Lbs; 1200fr/1160rr
Doug Jackson has weighed most all of the stock combinations. My car was weighed on a "truck scale"
My V6 has been set rearward of the front wheel centerline.
Perhaps someone can extrapolate the weights of the two engines to approximate the outcome ...
I am planning my next swap, putting a 302 into a 74&1/2 MGBGT. Already have all the "big pieces".
BTW, the V6 car really does handle great! Very neutral, unless provoked ...
|I am still working on my B/302. I have moved my 302 to where the the number 1 piston is behind the front x-member.I have heavily modified the cars sheetmetal( it was an ex-racer, with nothing but an old fiberglass seat and a roll cage.) I have used some tubing to make a tranny tunnel and also will double as frame support. I am making my own headers, they are not the best looking but I think it will work. My motor is a 68 302 with 66 289 closed chamber heads,I will use an edelbrock performer rpm/ edelbrock 600 four barrell carb, the bumpstick will be either an x-treme energy cam or 289 hi-po grind,all backed by a c-4 slushbox. Where are all the people that were planning on doing a 302 swap? mike|
This thread was discussed between 27/07/2000 and 29/07/2000
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