Dumb question 0n 427 BB
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,516
Likes: 505
From: Bussey, IA
Gary- what is an 049 or 781? Skunk - no offense taken. Thanks for putting your ho out there. Only way I am gonna learn! Gerry, dochp, and Tim- thanks for sharing the info on the diff on these things! Never heard that kinda stuff before!
Race Director
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
If you can afford aftermarket heads, I'd go with the oval port version of these and build it to 10 to 1 comp. ratio- http://www.brodix.com/cylinder-heads...block-series26
They have great flow and velocity and have stock height exhaust ports, so there's no guessing about header fitment. That combined with a true high performance dual plane intake and a cam similar to the one in my sig, and you'll have a very potent engine that's also truly streetable. If you go that route, plan on putting drag radials out back.
They have great flow and velocity and have stock height exhaust ports, so there's no guessing about header fitment. That combined with a true high performance dual plane intake and a cam similar to the one in my sig, and you'll have a very potent engine that's also truly streetable. If you go that route, plan on putting drag radials out back.
Drifting
Joined: Oct 2005
Posts: 1,527
Likes: 148
From: East London/SW Essex UK
If you can afford aftermarket heads, I'd go with the oval port version of these and build it to 10 to 1 comp. ratio- http://www.brodix.com/cylinder-heads...block-series26
They have great flow and velocity and have stock height exhaust ports, so there's no guessing about header fitment. That combined with a true high performance dual plane intake and a cam similar to the one in my sig, and you'll have a very potent engine that's also truly streetable. If you go that route, plan on putting drag radials out back.
They have great flow and velocity and have stock height exhaust ports, so there's no guessing about header fitment. That combined with a true high performance dual plane intake and a cam similar to the one in my sig, and you'll have a very potent engine that's also truly streetable. If you go that route, plan on putting drag radials out back.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,516
Likes: 505
From: Bussey, IA
The open chamber heads are better than the closed? I thought the closed would be better and give better compression. My current heads are 772s which are open. Supposedly this engine has been gone through and built up, but I know I will have to take it apart to find out how the is defined.
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Race Director
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
The open chamber heads are better than the closed? I thought the closed would be better and give better compression. My current heads are 772s which are open. Supposedly this engine has been gone through and built up, but I know I will have to take it apart to find out how the is defined.
Instructor
Joined: Oct 2007
Posts: 167
Likes: 1
From: Escondido CA
That really depends on the engine. First step is what do you have on hand? A complete 427 or just a block, that can help you decide where to take the build. The only trouble free performance upgrade is cubic inches most times. If it's just a block consider a 496, it'll cost the almost same in the end.
Last edited by badrad; Oct 7, 2013 at 04:41 PM.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
I ran my 427 with open chamber and a pretty hot cam for 9:1 compression. 260 duration @.050 and 560 lift. Was too much and low end torque sucked!
Lets just say I wasn't impressed since my past engine was a 455 olds!
Fast forward 2 years and I scored oval port close chamber 98cc heads
day and night comparison when it came to torque and hp!!!
The 455 olds would rotate the earth but that 427 would scream past it after 60ft.
93 octane was required after I swapped the heads but it was well worth every penny! Just something to consider if you really have fun with your car
Lets just say I wasn't impressed since my past engine was a 455 olds!
Fast forward 2 years and I scored oval port close chamber 98cc heads
day and night comparison when it came to torque and hp!!!The 455 olds would rotate the earth but that 427 would scream past it after 60ft.
93 octane was required after I swapped the heads but it was well worth every penny! Just something to consider if you really have fun with your car
Instructor
Joined: Oct 2007
Posts: 167
Likes: 1
From: Escondido CA
A complete engine is different since you have a crank and rods that are assumed good. 427 pistons are getting harder to find on the shelf and fairly expensive usually. If you have oval port heads that's a great start to a strong street engine. It all comes down to how much are you willing to invest into it? I would start with a solid plan of what you want out of the car and then focus your build around that.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,516
Likes: 505
From: Bussey, IA
I didn't have those in mind! MOre concerned about the kids in the area and my buddys with their 5.0 Stangs. Not even gonna try and take those on! Looking good though. And btw my current dd is 91 Z28!
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,516
Likes: 505
From: Bussey, IA
Also as my engine is a tall deck, I will either have to have spacers or go with a limited choice on aluminum intakes that are made to fit without the spacers. Anybody here have any experience with either choice? Give me the good, bad and ugly.
Instructor
Joined: Oct 2007
Posts: 167
Likes: 1
From: Escondido CA
There might be issues getting that in a Corvette. I've never seen a tall block dual plane intake, most guys throw big strokes in these for racing.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
A tall deck is going to make it really tight getting headers in there. If it's a tall deck, someone must have already done a performance rebuild- the tall decks had 4 ring pistons and were meant to be low RPM high torque engines. Both the 366 and 427 were used in C-60 and C-70 trucks.
I've worked a bunch of the 427's in trucks with a 5+4 trans and 4.11 tandem rear axles. On 10.00x20 tires. Drop 23 tons of rock on there and get busy. 20 forward gears and 4 in reverse.
I've worked a bunch of the 427's in trucks with a 5+4 trans and 4.11 tandem rear axles. On 10.00x20 tires. Drop 23 tons of rock on there and get busy. 20 forward gears and 4 in reverse.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,516
Likes: 505
From: Bussey, IA
Was thinking of going with standard manifolds for the exhaust. No leaks, no blown gaskets. The family that I got engine from said the son (now in jail, needed money for lawyer) put a bunch of money in engine and had it built up for performance. Had it in a pickup and rolled it (part of going to jail I understand) but is still running. Does have an Accell Super Coil HEI distrib (and MSD wires) so it is not stock. Supposedly has been cammed (I presume I can check that by removing timing chain cover and read cam) and had other work done to it. Much to check into.