460" to 514" or 521" comparison?

mdross1 · #1 (**permalink**) 01-22-2010, 08:32 AM

Probably making a mistake asking this question,only because I may be convinced to step it up a notch.
Question! Those of you that started with a 460 and stepped up to either a 514 or 521,or for that matter bigger still.In your best words describe the differences,things you like, difference in torque feel,off idle acceleration,lose traction.you know all the good stuff!

Mark O'Neal · #2 (**permalink**) 01-22-2010, 09:34 AM

Torque, more torque, and more torque than that.

mjmacqua · #3 (**permalink**) 01-26-2010, 05:36 PM

I had a 557 built, thought that would be a great idea. To be honest it was not. It ran way too hot, I could never get it cool enough and wound up pulling it and rebuilding. I had a 501 built with a milder cam. I dynoed at 570HP and 600lbs of torque. Way more than I will ever need. I made sure the builder (PCHS Racing, Bohemia NY) new exactly what I wanted, a driver with a lot of pep. I got just that, there arent many things that can stay with you from 0-70, after that, I dont care, I already won. But that cam is mild enough to run smoothly on a run. I would def modify the eng from the 460, and go with either the 501 or the 514. Just my opinion.

vector1 · #4 (**permalink**) 01-27-2010, 05:16 AM

Quote:

Originally Posted by Mark O'Neal

Torque, more torque, and more torque than that.

what he said.

Tom Wells · #5 (**permalink**) 01-27-2010, 05:20 AM

I have to recuse myself from this thread for obvious reasons

mdross1 · #6 (**permalink**) 01-27-2010, 01:36 PM

Mr Wells, you do not have ro recuse yourself as far as I am concerned.Enlighten us!

DocDirk · #7 (**permalink**) 01-27-2010, 03:34 PM

Well just a helluva question! I had a 533ci built and it has its plusses and minuses. First of all....good thing I still have about 1/2" of room between the engine and the compartment side walls at the corners, cuz it DO have some idle vibrate....and YES....overheating was the order of the day until I put one helluva puller fan into the shroud!! It lopes like it means business with a modest cam in it.... I'm beginning to wonder...since I have no track experience and drive it strictly street, whether sometimes it might be more fun to drive a slower car fast than a very fast car slow...know what I mean? I can walk this dog, but I can almost never let it off its leash haha!

......AND my wife just LOVES the car.

FUN though.... and all the oooohs and aaaaahhhhs that your ego can stand.

Regards,

Dirk

jdean · #8 (**permalink**) 01-27-2010, 07:17 PM

Started with a 460 and rebuilt to a 521 with a C6 automatic (Tom you can chime in now

.....Actually it was a relatively mild build at 537 HP and 580 TQ (through the Cobra headers as installed) but it would easily vaporize the tires through first and second and is the only automatic car I ever drove that would spin the tires on the 3rd gear shift. With that torque, you find yourself noticing the type of pavement on every road you drive on so you can deal with the smoother surfaces in case you wanted to nail it to pass someone and not spin sideways at 60.

It never overheated, but idling at a stop light in 100 degree Texas summer heat would make it climb to over 220.

Very fun engine but still pretty heavy as the only downside. Go for the 521 for relatively cheap and reliable gobs of power.

STL Mark · #9 (**permalink**) 01-27-2010, 09:09 PM

I have a 588 that makes 650 hp and 750 tq. I cannot floor the car without roasting the tires in any gear or at any speed. It scares the death out of me and I love it so.

I have smoked the tires at 70 gone sideways just a couple of times and thank my lucky stars I'm still here to write about it.

That much power in a small car is a great conversation piece, and that much power never actually makes it to the ground.

Silverback51 · #10 (**permalink**) 01-28-2010, 03:16 AM

Quote:

Originally Posted by STL Mark

I have a 588 that makes 650 hp and 750 tq. I cannot floor the car without roasting the tires in any gear or at any speed. It scares the death out of me and I love it so.

I have smoked the tires at 70 gone sideways just a couple of times and thank my lucky stars I'm still here to write about it.

That much power in a small car is a great conversation piece, and that much power never actually makes it to the ground.

I just looked at your pictures in your gallery. If you still have those Goodyear GT II's, get rid of them and put on some billboards. That will help your traction issue.

Ron61 · #11 (**permalink**) 01-28-2010, 04:46 AM

Quote:

Originally Posted by jdean

Started with a 460 and rebuilt to a 521 with a C6 automatic (Tom you can chime in now

.....Actually it was a relatively mild build at 537 HP and 580 TQ (through the Cobra headers as installed) but it would easily vaporize the tires through first and second and is the only automatic car I ever drove that would spin the tires on the 3rd gear shift. With that torque, you find yourself noticing the type of pavement on every road you drive on so you can deal with the smoother surfaces in case you wanted to nail it to pass someone and not spin sideways at 60.

It never overheated, but idling at a stop light in 100 degree Texas summer heat would make it climb to over 220.

Very fun engine but still pretty heavy as the only downside. Go for the 521 for relatively cheap and reliable gobs of power.

I had a friend here that built one but he used all aluminum inside and out that he could. The push rods were as large as my arm but weighed very little. He also had the C6 with a shift kit and bought the best tires he could get. I believe his dynoed out at around 600 horse and he was never able to really open it up as just touching the gas would burn the tires. He almost went through the front window of a store in town once and I believe he has sold the car since then.

Ron

Tom Wells · #12 (**permalink**) 01-28-2010, 07:52 AM

Well I guess I have the OK to say bigger is better.

Most of the time.

Doing a "snap spin" on street tires, on a public street isn't.... Especially when it's not intentional.

There are two places I've been able to floor it are the long straight at Sebring and the back straight at Daytona. Both on track tires.

Is it worth it? H?LL YES!

I'm now putting a 557 into a Zephyr wagon for street use.

After that, the Cobra will get a 604.

Can you tell I'm hooked?

Tom

PS: Just be careful!

D-CEL · #13 (**permalink**) 01-28-2010, 11:33 AM

mdross1,

Not a mistake, good question. The size difference is near inconsequential @ 7 CI, which, all things being equal maybe 10-15hp.
I would think that either size would allow you to achieve most power goals.
More important would be compression, cylinder heads and cam specs.
Both sizes could make monster power with good heads and the right cam.

Jason

mdross1 · #14 (**permalink**) 01-28-2010, 01:42 PM

Quote:

Originally Posted by STL Mark

I have a 588 that makes 650 hp and 750 tq. I cannot floor the car without roasting the tires in any gear or at any speed. It scares the death out of me and I love it so.

I have smoked the tires at 70 gone sideways just a couple of times and thank my lucky stars I'm still here to write about it.

That much power in a small car is a great conversation piece, and that much power never actually makes it to the ground.

Now this is the meat I was looking for,can only imagine what that 588 must feel like if the tires could hookup.A 514 or 521 makes more sense when it comes to planting the power.My 460 on street tires can get out of hand in the twisties,maybe a good set of tires is all I really need.Thanks to all of you,now deciding will so much easier.