427 re-build recommendations
Thread Starter
Le Mans Master
Joined: Feb 2015
Posts: 8,784
Likes: 27
427 re-build recommendations
I have a 1969 427/390 with 96k that is in the machine shop for a refresh.
It is all original except for the intake (which is a 71 454 pass car low hp).
I'm looking for stock or a little better performance and more important, reliability and able to run on 91 octane. The shop said the cylinder walls are scared from rust and will have to be bored 30 over, they said oddly enough the cam barely seems broken in and is stock, so it must have been replaced. The valves are shot as well. So following are my questions.
I will need new pistons and probably rods, what do you recommend ?
New valve (brand) recommendations ?
Do I replace the non vette intake, and if so with what ?
If I replace the intake, what do I do with the original carb, use or replace ?
Any other recommendations welcome
It is all original except for the intake (which is a 71 454 pass car low hp).
I'm looking for stock or a little better performance and more important, reliability and able to run on 91 octane. The shop said the cylinder walls are scared from rust and will have to be bored 30 over, they said oddly enough the cam barely seems broken in and is stock, so it must have been replaced. The valves are shot as well. So following are my questions.
I will need new pistons and probably rods, what do you recommend ?
New valve (brand) recommendations ?
Do I replace the non vette intake, and if so with what ?
If I replace the intake, what do I do with the original carb, use or replace ?
Any other recommendations welcome
Drifting
Joined: Jan 2014
Posts: 1,866
Likes: 140
From: Sadieville Kentucky
I have a 1969 427/390 with 96k that is in the machine shop for a refresh.
It is all original except for the intake (which is a 71 454 pass car low hp).
I'm looking for stock or a little better performance and more important, reliability and able to run on 91 octane. The shop said the cylinder walls are scared from rust and will have to be bored 30 over, they said oddly enough the cam barely seems broken in and is stock, so it must have been replaced. The valves are shot as well. So following are my questions.
I will need new pistons and probably rods, what do you recommend ?
New valve (brand) recommendations ?
Do I replace the non vette intake, and if so with what ?
If I replace the intake, what do I do with the original carb, use or replace ?
Any other recommendations welcome
It is all original except for the intake (which is a 71 454 pass car low hp).
I'm looking for stock or a little better performance and more important, reliability and able to run on 91 octane. The shop said the cylinder walls are scared from rust and will have to be bored 30 over, they said oddly enough the cam barely seems broken in and is stock, so it must have been replaced. The valves are shot as well. So following are my questions.
I will need new pistons and probably rods, what do you recommend ?
New valve (brand) recommendations ?
Do I replace the non vette intake, and if so with what ?
If I replace the intake, what do I do with the original carb, use or replace ?
Any other recommendations welcome
Le Mans Master
Joined: Mar 2001
Posts: 5,738
Likes: 644
From: Lincoln, CA
Depends on which direction you want to go while you have it apart. You could stroke it, rebuild it as a 427 with a 30 overbore with all new parts and Roller cam or just do a factory rebuild.
The builder should be able to guide you.
Is the current setup a Qjet? You could try and get a 69 L36 intake.
The builder should be able to guide you.
Is the current setup a Qjet? You could try and get a 69 L36 intake.
Team Owner
Joined: Jun 2000
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Likes: 1,481
From: Southbound
Cruise-In II Veteran
Team Owner
Joined: Feb 2003
Posts: 54,073
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From: Sitting in his Nowhere land Hanover Pa
2024 C2 of the Year Finalist - Unmodified
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if you only want to rebuild it stock tell them you want all federal mogul parts. not only will they be cheaper they are built to OEM specs and available at any local parts store
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
I have a 68 L36, which is rebuilt .030" over basically stock, with a mild modern grind Crane cam. If I were you, I would go stock with a mild roller cam. I would look for a stock intake manifold; I have no idea what they are going for nowadays.
If you want the next level of performance, look at aftermarket heads.
Oh yeah, all big blocks love headers...
Important: Make sure your machinist does not mill off the block stamp numbers.
Don't ask me how I know...
Mine are pretty light...
If you want the next level of performance, look at aftermarket heads.
Oh yeah, all big blocks love headers...
Important: Make sure your machinist does not mill off the block stamp numbers.
Don't ask me how I know...
Mine are pretty light...
Last edited by Jeff_Keryk; Apr 16, 2016 at 10:37 AM.
Thread Starter
Le Mans Master
Joined: Feb 2015
Posts: 8,784
Likes: 27
Depends on which direction you want to go while you have it apart. You could stroke it, rebuild it as a 427 with a 30 overbore with all new parts and Roller cam or just do a factory rebuild.
The builder should be able to guide you.
Is the current setup a Qjet? You could try and get a 69 L36 intake.
The builder should be able to guide you.
Is the current setup a Qjet? You could try and get a 69 L36 intake.
People want outrageous money for those 69 l36 intakes (600-950) and I can get a 67 for less than 200
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Thread Starter
Le Mans Master
Joined: Feb 2015
Posts: 8,784
Likes: 27
Machine shop is different than the builder, so yes both said the same thing. The car sat for very long periods of time, and the PO did not change fluids or oil.
Thread Starter
Le Mans Master
Joined: Feb 2015
Posts: 8,784
Likes: 27
engine builders and machine shops are known to do this and always want to build the engine to there liking not caring what the customer wants.
if you only want to rebuild it stock tell them you want all federal mogul parts. not only will they be cheaper they are built to OEM specs and available at any local parts store
if you only want to rebuild it stock tell them you want all federal mogul parts. not only will they be cheaper they are built to OEM specs and available at any local parts store
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
A dream build, or a bats nightmare build hum,
IF I had a 427 I believe I would have to build what I will call a L-88 tribute engine, I might do it with my 454 while the real L-88 was a bit radical for a good street engine I would talk with a couple seasoned engine techs I know, there are also a couple good ones on here that know their stuff and a lot who do not but think they do...
So get aluminum heads, hydraulic roller cam, keep cam and compression within that pump gas goldilocks zone, paint and dress that engine to look like an old L-88, get just the right sounding cam and exhaust, it would still melt the tires yet be far more streetable
IF I had a 427 I believe I would have to build what I will call a L-88 tribute engine, I might do it with my 454 while the real L-88 was a bit radical for a good street engine I would talk with a couple seasoned engine techs I know, there are also a couple good ones on here that know their stuff and a lot who do not but think they do...
So get aluminum heads, hydraulic roller cam, keep cam and compression within that pump gas goldilocks zone, paint and dress that engine to look like an old L-88, get just the right sounding cam and exhaust, it would still melt the tires yet be far more streetable
Team Owner
Joined: Feb 2003
Posts: 54,073
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From: Sitting in his Nowhere land Hanover Pa
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Drifting
Joined: Jan 2014
Posts: 1,866
Likes: 140
From: Sadieville Kentucky
A dream build, or a bats nightmare build hum,
IF I had a 427 I believe I would have to build what I will call a L-88 tribute engine, I might do it with my 454 while the real L-88 was a bit radical for a good street engine I would talk with a couple seasoned engine techs I know, there are also a couple good ones on here that know their stuff and a lot who do not but think they do...
So get aluminum heads, hydraulic roller cam, keep cam and compression within that pump gas goldilocks zone, paint and dress that engine to look like an old L-88, get just the right sounding cam and exhaust, it would still melt the tires yet be far more streetable
IF I had a 427 I believe I would have to build what I will call a L-88 tribute engine, I might do it with my 454 while the real L-88 was a bit radical for a good street engine I would talk with a couple seasoned engine techs I know, there are also a couple good ones on here that know their stuff and a lot who do not but think they do...
So get aluminum heads, hydraulic roller cam, keep cam and compression within that pump gas goldilocks zone, paint and dress that engine to look like an old L-88, get just the right sounding cam and exhaust, it would still melt the tires yet be far more streetable
The only major difference in the L 88 is the heads .Rods are same and I would suggest an aftermarket rod anyway .Heads on L 88 are closed chamber which get's you 12.5 comp .too high for street use .I would recommend roller cam flat top piston AND PORT AND POLISH EXISTING HEADS over the counter manifold ,have quadrajet reworked by Lars or Custom carb .Just my 1c worth
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
I recently rebuilt a 427. Used Sealed Power L 2300 pistons. Have the rods reconditioned. For a low maintenance street engine keep the hydraulic flat tappet cam. It will develop loads of torque and will run nicely on the street. Plus, it won't cost an arm and a leg.
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
Bats
The only major difference in the L 88 is the heads .Rods are same and I would suggest an aftermarket rod anyway .Heads on L 88 are closed chamber which get's you 12.5 comp .too high for street use .I would recommend roller cam flat top piston AND PORT AND POLISH EXISTING HEADS over the counter manifold ,have quadrajet reworked by Lars or Custom carb .Just my 1c worth
The only major difference in the L 88 is the heads .Rods are same and I would suggest an aftermarket rod anyway .Heads on L 88 are closed chamber which get's you 12.5 comp .too high for street use .I would recommend roller cam flat top piston AND PORT AND POLISH EXISTING HEADS over the counter manifold ,have quadrajet reworked by Lars or Custom carb .Just my 1c worth
L-88's didnt run qjets did they?
L-88s ran the big old rectangle post heads which are also not a great street head for the build I was thinking of....
The fact is there are cats on this forum who have built far more street friendly BB's that would spank the old L-88s
Drifting
Joined: Jun 2005
Posts: 1,950
Likes: 498
From: Chino Hills CA
I would go with a mild hydraulic tappet cam, 125-130 degree, if you still have a q-jet, go with an Edlebrock performer, or maybe a performer air gap. And since you're going .030 over, don't forget to tell everyone you have a 433, not a 427.