81 motors
Thread Starter
Instructor
Joined: Mar 2013
Posts: 108
Likes: 1
From: Georgia
81 motors
Are the 350s in the 81s 4 bolt or 2 bolt mains? I'm going to put a supercharger on my vette and I needed to find out if I can take the motor in the car apart and use it or find a 4 bolt and build it while I keep driving the car.
I car is a hobby for me so it doesn't matter if it sits while I put the motor together. I found a ZZ4 motor new on crate for $2200 but the pistions are not forged and the compression is too high. I don't think it will work. I'm not looking to race it. I just want it to sound good and look good at car shows.
Thanks
I car is a hobby for me so it doesn't matter if it sits while I put the motor together. I found a ZZ4 motor new on crate for $2200 but the pistions are not forged and the compression is too high. I don't think it will work. I'm not looking to race it. I just want it to sound good and look good at car shows.
Thanks
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
If you're not going to race it, why worry if the ZZ4 HO motor doesn't have 'forged pistons'? Or 'High Compression'? Yet, you want to put a blower on there. Are you talking about an accessory belt-driven supercharger, or an all out BDS, Dyers 6-71 or gawd, 8-71, sticking out of the hood?
My '74, with a modded L48 motor with the ZZ4 (L98 Aluminum) heads sounds plenty rowdy, through single stage Flowmasters! And it goes like hell too! If you go with the ZZ4 motor and top it off with a Holley 650 Double Pumper, with Mechanical Secondaries, I guarantee, it's going to snap your head back hard and you will be plenty pleased with your performance (unless you grew up with LS6 454's, L88's or anything of that kind, which were almost 'stupid fast'!).
My '74, with a modded L48 motor with the ZZ4 (L98 Aluminum) heads sounds plenty rowdy, through single stage Flowmasters! And it goes like hell too! If you go with the ZZ4 motor and top it off with a Holley 650 Double Pumper, with Mechanical Secondaries, I guarantee, it's going to snap your head back hard and you will be plenty pleased with your performance (unless you grew up with LS6 454's, L88's or anything of that kind, which were almost 'stupid fast'!).
Thread Starter
Instructor
Joined: Mar 2013
Posts: 108
Likes: 1
From: Georgia
I have a Dyers 6-71 sitting on the shelf. I was going to pull my motor, put all the forged bottom end in it, mount the blower, buy an aftermarket stylish hood, cut it out, and look pretty. It looks like my first job will be to find a 4 bolt motor.
Racer
Joined: Oct 2010
Posts: 323
Likes: 9
I would like to stick up for 2 bolt main blocks, now if given a choice I would choose a 4 bolt, but 2 bolts can handle quite a bit of horsepower.
I've had two different grand nationals in the past, and even though neither of them were insanely fast, I knew plenty of people that pushed those ~3600 lb cars with the aerodynamics of a brick wall to over 130 mph in the quarter.
As long as you didn't make too bad of a mistake, the stock two bolt bottom end would stay together in 650 hp cars, and by the way, their stock pistons were cast and put up with up to 30lbs of boost sometimes.
In fact I would probably take a 2 bolt main with ARP bolts and strong main caps over a stock 4 bolt any day.
One last thing, you want to put a blower on the car? To each his own, my last car before my current 81, was a 2001 Z06. It had 385 hp stock and the car was just ridiculously fast to me. I really can't imagine too many people taking it out thrashing it, and come back thinking it was underpowered. I didn't have near the skill to handle all the power it had.
Imo you can make plenty of power out of a normally aspirated 350 to make most people happy.
Just my.02
I've had two different grand nationals in the past, and even though neither of them were insanely fast, I knew plenty of people that pushed those ~3600 lb cars with the aerodynamics of a brick wall to over 130 mph in the quarter.
As long as you didn't make too bad of a mistake, the stock two bolt bottom end would stay together in 650 hp cars, and by the way, their stock pistons were cast and put up with up to 30lbs of boost sometimes.
In fact I would probably take a 2 bolt main with ARP bolts and strong main caps over a stock 4 bolt any day.
One last thing, you want to put a blower on the car? To each his own, my last car before my current 81, was a 2001 Z06. It had 385 hp stock and the car was just ridiculously fast to me. I really can't imagine too many people taking it out thrashing it, and come back thinking it was underpowered. I didn't have near the skill to handle all the power it had.
Imo you can make plenty of power out of a normally aspirated 350 to make most people happy.
Just my.02
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Thread Starter
Instructor
Joined: Mar 2013
Posts: 108
Likes: 1
From: Georgia
I will most likely use the 2 bolt after thinking about. I have also ways thought the 81s had the best lines and I've always wanted a blower motor in one. I just love the look and the attention they get when one pulles up to a show.
Again, I'm doing this for shows not racing and I think this will be fine just as phinfan said. The car has been around a 6.5 ~ 7 on a scale from 1~10. I'm going to spend the winter repainting, and going through the drivetrain. I'm probably going to go with a 3.08 gear, 700R trans, and the blower.
There's just a lot of work to transform a 6.5 to a 9~10 but it's time. The winter is coming, I have a 40 X 40 shop with a full size paint booth and this car sitting in it all by itself. The kids are gone to college and the last full restoration I did was back in 2000.
Thanks for all the input guys.
Again, I'm doing this for shows not racing and I think this will be fine just as phinfan said. The car has been around a 6.5 ~ 7 on a scale from 1~10. I'm going to spend the winter repainting, and going through the drivetrain. I'm probably going to go with a 3.08 gear, 700R trans, and the blower.
There's just a lot of work to transform a 6.5 to a 9~10 but it's time. The winter is coming, I have a 40 X 40 shop with a full size paint booth and this car sitting in it all by itself. The kids are gone to college and the last full restoration I did was back in 2000.
Thanks for all the input guys.