Mustang and Ford Performance Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
Ditching the 2V and putting a real engine in my GT. I love the 99-04 Mustangs but hate the mod motors.. Rounding up all the swap parts, AJE K-member & mounts, manual steering and brake conversion & Dynatech headers. Going to build a nice T-400 to put behind the blown big block. Going to be a fun project I will post updates when I can. 35757792_2144188122277913_4354136642370404352_o.jpg

- - - Updated - - -

View attachment 169057
 

·
Breaking ****
Joined
·
1,304 Posts
What springs are you running to hold up that boat anchor lol...JK should be a monster when done

Sent from my SM-G900T using Tapatalk
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #3 ·
Hello, not sure yet. Going to get it in and see how it sits. Running coil overs with Bilstein struts now.
 

·
Administrator
Joined
·
9,417 Posts
You do know that the engine in your pic is an SBC not a BBC ...


Ed
 

·
Administrator
Joined
·
9,417 Posts
For some reason your attachments are not displaying, Bubbaman.

With respect to your engine, the Term BBC is used to describe the Chevrolet engines made from 1958 through today. They all shared a common block metric that was bore spacing. All Chevrolet big blocks produced by GM had 4.84" bore centers.

The original big blocks in 1958 were known as the "W" series engines. All had cast iron blocks and were available in displacements of 348, 409 and 427 cubic inches. The visual identifier for this series of Chevrolet big blocks was what was known as the "W" shaped valve cover and their in block rather than in head combustion chamber. This is an pic of an early 409 engine from the "W" series engine family with a single four barrel. The unique valve cover arrangement is clearly visible.

409.1.jpg

The engine displacement was increased in 1963 to 427 cubic inches and a raised port cylinder head and matching manifold were introduced for the engine. The interesting thing about this is that Chevrolet had a new Mark IV engine already under development for the 1964 year but felt compelled to enhance the "W" series family one last time with the raised port larger displacement Z11 427. This is a picture of a Z11 and the increase in port height and manifold runner is clearly evident.

Z11 427.jpg

The Mark IV engine was developed essentially for NASCAR and maintained the 4.84" bore centers of the earlier "W" series engines and the 427 cubic inch displacement of the Z11. The Mark IV engines eventually evolved into the 427 and 454 big blocks of the muscle era and were available in either cast iron or aluminum from Chevrolet. This is a pic of a typical production Mark IV engine.

Mark IV.jpg

The Mark IV family of Chevrolet big block engines used a cylinder head design originally put into production vehicles by Chrysler on their 318 cubic inch engines. The design used what was marketed as a polysphere combustion chamber but in actual fact was a wedge chamber. The significant technological difference between the polysphere design and a traditional wedge chamber was the fact the valves were no longer in line. The benefit of the canted valve head design was that both the intake and exhaust valve could be positioned so as to optimize the port's short side radius providing hemispherical like port shaping for both intake ports and exhaust ports without the bulk or expense of the hemi head casting geometry. This is a picture of the head where the valve cant and port efficiencies are clearly visible.

MK IV Head.jpg

When Ford came out with their single overhead cam 427 both GM and Chrysler were quick to respond with their own variations on the theme. Chrysler went to a DOHC 4V version of their 426 and GM went to a SOHC 2V version of their Mark IV engine that had a stunning resemblance to the Ford 427 SOHC engine. Below is a pic of that infrequently seen engine. As soon as NASCAR put the kabosh on cammers both GM. and Chrysler shelved their OHC engine programs.

MK IV SOHC 427.jpg

Easily the longest running production engine for Chevrolet was their small block series that ran from 1955 into the 90's. It was available in displacements from 265 cubic inches up through 400 cubic inches with a variety of deck heights and heads. Most all heads were inline valving with one exception that GM referred to as the SB2 design. The SB2 design used a standard 4.400" bore space small block but with an extraordinary set of canted valve heads strikingly similar to the Mark IV engine. This is a pic of the GM SB2 head design.

GM SB2.jpg

This is a picture of the port corrected aftermarket SB2 design. The Aftermarket design made all four intake ports and all four exhaust ports the same. the SB2 engine was the official NASCAR engine for GM until Detroit began using purpose designed and built pure race engines for NASCAR.

Race SB2.jpg

Now we get to your engine. What you have is known as a GM LS based small block engine. It is based on the same small block bore spacing as the original 265 generation small blocks. It also shares the same small block bore spacing as Ford's 221/260/289 /302/351 series small block engines.

The LS family of GM engines was introduced in 1995 and built using the same lifters, cylinder bore spacing and even rod bearings that the original Chevrolet small block engines used. The new generation LS series small block GM engines have been manufactured in three different generations or variations of the basic platform, Gen III, Gen IV, and Gen V. The Gen I and Gen II variations on the them were based on the original 1955 small block design. In 2014 GM recycled the earlier LT SBC engine name designation for a new generation of LS engines.

The LS engine family like its 265/283/302/327/350/400 family predecessors share a small block 4.400 inch bore center but have incorporated a deep skirt block design with cross bolted mains similar to the Ford and Chrysler nascar designs of the 1960's for increased block rigidity. The block has also undergone considerable top end design changes to also improve block rigidity.

To get increased displacements with its SBC 4.400 bore centers the LS family engines adopted the 400 inch SBC's 4.125" bore size for all but their supercharged engines. The 4.125" bore size on a 4.400" SBC bore center did not provide sufficient web thickness between bores for adequate gasket sealing in a supercharged application. After in-house reliability testing Chevrolet opted to reduce supercharged engine bore sizes for thicker cylinder walls, increased web thickness between bores and improved gasket sealing at the 4.400" SBC bore spacing in supercharged form.

The cylinder head design for the LS engines went back to a traditional inline valve, wedge chamber design but did so with taller heads and ports to improve port flows. In the end what you have is a modern GM small block that has been stroked to earlier big block displacements but importantly it is not a big block it is a modern light weight, thinner wall casting, small block. The latest iteration of the original 1955 SBC design with improved cylinder block structural strength and integrity.

In the FWIW category, the blower that is on top of your engine in the first pic is a traditional roots blower. It is by far the most inefficient of all the PD blower choices available to you. Additionally there does not appear to be any visible intercooling which that blower design badly needs. There is something that appears to be beneath the blower that could be an intercooler or possibly a highly polished manifold reflecting the blower case.

Assuming you actually use a supercharged LS generation engine it would be to your advantage to use the technology GM has already developed for their supercharged 650 HP LT4 engines. You would save a lot of money, and pick up considerable reliability and performance - of course that assumes you have not already spent the money to buy what is in your first pic.

Ed
 

·
Administrator
Joined
·
9,417 Posts
Bubbaman,

My bad! I stand corrected, you are right. It is a BBC 454. As I was looking at the front of the block I could make out a stamped steel timing cover and the water pump attaching bosses for a BBC. The pic wasn't clear enough for me to see the exhaust side of the head so I was puzzled by the rocker cover attachment which prompted closer inspection that turned up a non LS, MK IV front on the block.

Ed
 

·
Registered
Joined
·
792 Posts
Any updates?
 

·
Registered
Joined
·
1 Posts
Ditching the 2V and putting a real engine in my GT. I love the 99-04 Mustangs but hate the mod motors.. Rounding up all the swap parts, AJE K-member & mounts, manual steering and brake conversion & Dynatech headers. Going to build a nice T-400 to put behind the blown big block. Going to be a fun project I will post updates when I can. View attachment 169055

- - - Updated - - -

View attachment 169057
hey did u ever finish this and did u have to do anything special for it to fit in the engine bay
 
1 - 11 of 11 Posts
Top