427 -?
Thread Starter
Burning Brakes
Joined: Jul 2007
Posts: 864
Likes: 2
From: Jax FL
427 -?
please excuse my ignorance (it comes natural for some of us)
but what exactly is a 427 in a C5? I have noticed a few vettes for sale as 427's and to my ol'noggin, it means 427ci......is that still the case? or is it code for hp ? or what?...and what are the good and bad of what ever a 427 is now days??
thanks in advance.......and yes in August I will be back in a c5
of some configuration.....sold my eb coupe last year and have regretted it ever since
but what exactly is a 427 in a C5? I have noticed a few vettes for sale as 427's and to my ol'noggin, it means 427ci......is that still the case? or is it code for hp ? or what?...and what are the good and bad of what ever a 427 is now days??
thanks in advance.......and yes in August I will be back in a c5 of some configuration.....sold my eb coupe last year and have regretted it ever since
Melting Slicks
Joined: Feb 2002
Posts: 2,956
Likes: 2
From: Indianapolis In
please excuse my ignorance (it comes natural for some of us)
but what exactly is a 427 in a C5? I have noticed a few vettes for sale as 427's and to my ol'noggin, it means 427ci......is that still the case? or is it code for hp ? or what?...and what are the good and bad of what ever a 427 is now days??
thanks in advance.......and yes in August I will be back in a c5 of some configuration.....sold my eb coupe last year and have regretted it ever since
but what exactly is a 427 in a C5? I have noticed a few vettes for sale as 427's and to my ol'noggin, it means 427ci......is that still the case? or is it code for hp ? or what?...and what are the good and bad of what ever a 427 is now days??
thanks in advance.......and yes in August I will be back in a c5 of some configuration.....sold my eb coupe last year and have regretted it ever since 
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The new 427 is a bored and stroked small block.
Le Mans Master
Joined: Sep 2007
Posts: 7,604
Likes: 8
From: Belleville Il
Well there actually are bored and stroked 427s and I'm sure there are now LS 7s from the C6-Z06 as they have been available as crate motors from GM for several years now. One of our club members dropped one in his C5 vert a coupe of years ago
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Le Mans Master
Joined: Aug 2002
Posts: 8,222
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From: Norfolk VA
a 427 in a C5 is going to be aftermarket work, not a factory option on any C5. Could be a bored/stroked LS1/6 a C5R block or an LS7 from the C6Z and probably some other options too and that's before you even start talking about head/cam options or what internals are in the engine, who built it and what shop installed it. It can be done right or you can cut corners. If you're looking at buying one, ask a lot of questions so you know what you're getting.
That said, when you find a good one, you're probably going to get a good deal because the car is going to be worth a lot less that what the original owner put into it or what it would take to build one yourself.
That said, when you find a good one, you're probably going to get a good deal because the car is going to be worth a lot less that what the original owner put into it or what it would take to build one yourself.
Team Owner
Joined: Jul 2004
Posts: 24,652
Likes: 298
From: NJ
St. Jude Donor '05-'08
We installed a ls7 with dry sump in my car. Very nice option.
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Melting Slicks
Joined: Mar 2005
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From: North Port Fl
Team Owner
Joined: Jul 2004
Posts: 24,652
Likes: 298
From: NJ
St. Jude Donor '05-'08
I posted some time ago the mpg I got on the highway back from carlisle but I don't remember and at the time I had 373 gears. Now I have 342 gears and the car sees mostly only track time which I average 8.2 mpg which is up from my 346 h/c setup.
I will look for the post of mpg. My guess is it was low 20s. If I can't find it I will take it for a drive and get some new numbers.
Burning Brakes
Joined: Apr 2009
Posts: 946
Likes: 2
a 427 in a C5 is going to be aftermarket work, not a factory option on any C5. Could be a bored/stroked LS1/6 a C5R block or an LS7 from the C6Z and probably some other options too and that's before you even start talking about head/cam options or what internals are in the engine, who built it and what shop installed it. It can be done right or you can cut corners. If you're looking at buying one, ask a lot of questions so you know what you're getting.
That said, when you find a good one, you're probably going to get a good deal because the car is going to be worth a lot less that what the original owner put into it or what it would take to build one yourself.
That said, when you find a good one, you're probably going to get a good deal because the car is going to be worth a lot less that what the original owner put into it or what it would take to build one yourself.
Racer
Joined: Oct 2005
Posts: 367
Likes: 3
From: maple grove and North Port fl mn and now florida
I have an LS7 427 in my C5. It was built to make a ton of HP and does. It has a blower that runs 17 lb boost and a little nitrous, thus 1000+ hp and I still get over 24 mpg on the highway and it is very driveable. Hope that helps, but as stated above make sure the car was built properly or it will be a big headache and a money pit to correct.
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Team Owner
Joined: Jul 2004
Posts: 24,652
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From: NJ
St. Jude Donor '05-'08
At the time built it was mn6 with 373. I liked that setup but I was running out of gear at different road courses so I opted to go back to 342s.
Although on the street I don't like the 342s as much they really make a difference on the track giving more room to stretch her out without having to shift as much.
Although on the street I don't like the 342s as much they really make a difference on the track giving more room to stretch her out without having to shift as much.
Team Owner
Joined: Jul 2004
Posts: 24,652
Likes: 298
From: NJ
St. Jude Donor '05-'08
