I would not use aluminum. I am building a similar block the Buick 350. Extra bore and stroke to 380 cubes. The shop is making a block girdle the the turbo v6 cars run. They also run billet mains on turbo v6 cars. So that might be what you want to use.

 

The Rover motors made into the early 2000s are dimensionally identical with the Buford and have cross-bolted mains from the factory. Simply get a 3.9 or 4.6 liter Rover short block. I did this to replace the 215 in my 1962 Olds F85.

 

Here's a picture of the Rover block. Note the cross bolts.

Here are the stock Rover caps for cross-bolted blocks.

Here's a link to an article that you may find useful.

 

Main caps are typically cast iron the weakest, cast nodular iron a lot stronger, machined mild steel like 1040-1050 to low alloy 5140 series which are really strong, or 4340 which is super strong but none are really not what the aluminum Buick needs. What it needs like all aluminum blocks is either cross bolts or a girdled set of mains machined from a single piece of metal. Aluminum blocks want to spread away from the crank which leads to bottom end failures. Contemporary aluminum V6 and V8 blocks have all gone this way. Even Chrysler had bottom end trouble with the first inline slant 6s which were aluminum, their solution was to switch back to cast iron. A good reference for aluminum blocked engines is to look at the liquid cooled V aircraft engines from WW II. Everyone from England, Germany, or the United States feature either cross bolts or a separate girdle that is one piece with the main caps. Either solution keeps the bottom end aligned and adds a lot of strength to the block.


Bogie

 

Main caps are typically cast iron the weakest,

This is true, but stiffness is probably more important than strength in the caps for most applications. Cast iron has nearly the same stiffness as steel and about three times the stiffness of aluminum. It's deflections in the caps that cause the majority of the problems, not strength-related failures.

 

Well, health has prevented much progress. Doc has said I can't do any heavy work after my 10th hernia, nothing over 7 pounds. **** to get old. Anyway I have gotten the heads from TA Performance and a beautiful crassram sequential efi system from John Eales in England speced to go with the cam, weight of car and gearing of the rearend and r200-4. Sweet unit. Here is a pic of the intake and the splash guard over the cam.

Next projects are to have a girdle cut to fit between the block and oil pan and modify the distributor by replacing the points cam with a Ford cam sensor to provide the signal for sequential firing.

Randy

 

Randy, beautiful work. Did you make the Splash Guard over the Cam? Is this something that could be purchased?

 

TA Rockers & Heads

Here are pictures of the new rockers and heads:

Will post pics of the heads when I can get someone over to lift one out of the box. about 23#'s each. The rockers are the shaft mounted roller rockers here are the standard specs for the heads from TA's website:

TA Performance’s Rover V8 aluminum cylinder heads are the best performing heads for the popular Rover V8 engines produced from 1967-2004. Based upon our V6 cylinder head, these heads are a great improvement over the factory and other aftermarket Rover cylinder heads.

The major area of improvement in the performance of these heads is the improved intake and exhaust ports. Out of the box, these heads flow 225 cfm intake and 135 cfm exhaust. With porting, this head can easily yield 260 cfm on the intake and 190 cfm on the exhaust ports. In addition, the valve angle has been adjusted to 13° to put the valves on the centerline of the bore which allows for the use of larger valves, up to 2.02” intake and 1.60” exhaust. The exhaust ports have also been raised 3/4” to help improve performance. These heads also feature a 1.850”-1.900” valve spring install height which allows for the use of higher lift cams. On 10.5:1 Compression engines, out of the box performance is usually 40+ HP.

Another feature that was incorporated during the design is the new 35-37cc combustion chamber shape. Factory Rover cylinder heads feature a D shaped combustion chamber. The new TA Rover head features a Heart shaped combustion chamber found on all high performance cylinder heads, including our V6 and big block heads. This results in better combustion and a decrease in the possibility of detonation, due to the more compact chamber, which increases performance. The chamber and deck thickness was also increased to at least 5/8” or thicker. This makes the heads stronger so they can handle more power without flexing and cracking, a potential problem on high horsepower or forced induction engines. The valve cover rail has also been raised to make way for additional material which gives you the ability to raise the intake ports to make it a tall port head. A raised runner provides a more direct flow to the valve resulting in additional CFM over the standard port head, approximately 10-15 CFM on average. Accessory bolt hole patterns for both the 14 and 10 bolt Rover heads have also been incorporated so that the heads fit the early 14 bolt and the later 10 bolt Rover blocks.

While this cylinder head was designed for the Rover V8, it will also bolt on to Buick 300/340 blocks with minor modifications. The stock Rover exhaust should bolt right up, but as the exhaust ports have been raised 3/4” fit there may be some fitment issues on some cars. In addition to the Rover valve cover bolt pattern, the 350 Buick valve cover bolt pattern has been incorporated on these heads allowing the use of 350 Buick valve covers for better clearance with roller rockers or for those looking to use these heads on a Buick 300/340. These heads will require new rocker arms, the stock rocker arm setup is not compatible with these heads. There are two options, shaft mounted roller rockers (TA 1309B) or Chevy style pedestal mount roller rockers. TA offers a wide variety of pedestal mount roller rockers (TA 1309C/D series), or you can use any other Chevy roller rocker but pedestal roller rockers will require the use of our guide plates (TA 1309GP - $35.00). Note: Requires the fabrication of a lifter tray cover. Uses 11/32” diameter valves 5.060” in length.

Randy

 

Here are pictures of the new rockers and heads:

Will post pics of the heads when I can get someone over to lift one out of the box. about 23#'s each. The rockers are the shaft mounted roller rockers here are the standard specs for the heads from TA's website:

You're building a 215, right?

After inspecting a pair of assmbled TA Rover heads with 1.94/1.6" valves, I wasn't sure they would clear but they do fit as advertised though you need the larger bore of the Buick 300 for them to fit the bore. Even the smaller valves won't fit a Buick 215 or Rover 3.5L block 3.5" bore blocks

TA ROVER/BUICK heads

 

Rather than spending a bunch of money on a custom machined girdle, get a Rover 4.6 block that already has cross-bolted mains. The 215 architecture is a deep skirt block. A separate girdle will be problematic.

 

Thanks

We used to build these blocks back in the 60's for use in SCCA destroked to 2.0L. This is one of the blocks that was left in the machine shop when it shut down (was resleeved to take Chevy 305 pistons). Got it for nothing. We used to do the girdles without a CNC machine, I am doing a CAD file and can have it cut for nothing. With the offset rod journals on the 300 crank I have over 300 cubes. Really don't want to get a Rover block at this late date. This project was actually started back in the late 80's before inexpensive Rover large liter units were available.

Thanks for the recommendation.

Randy