Cosworth Vega engine

[fheckro]

Does anyone know of an iron block with the same cylinder spacing and the aluminum cosworth vega block.
I need something a little stronger than the stock aluminum. we are racing a 76 Cosworth and want to but 14:1 compression and turn it to 8 or 9g. Maybe spray it.
I have heard that the stock blocks suck and need to find a reasonable alternative. The head looks awesome though. too bad they didn't take advantage of any of it's potential.
Thanks
Fred

[hammerdown7]

There is no iron block of similar dimensions. What type of racing are you planning to do? Cosworth of England, when they ran in Group 2 sports cars, cracked or split blocks after 2-3 hours in enduro racing so it does depend on what duty cycle you plan on running. COE engines were making 270HP. I pit crewed for a Cosworth Vega midget owner in the middle 90's. The stock block can handle around 250HP, above that it is suspect. The midget was running a HD block, GM made about 50 of these, and the owner experimented with lightening the crank. The crank was not balanced correctly and cracks formed above the mains. He then went to a stock block, the engine dyno'd at 300HP at 9000RPM, running 14:1CR on methanol. He made external re-inforcing aluminum plates that tied the top of the block to the bottom (I only have one picture of the right side of the engine with the plate, see below). The left side used three turn buckles plus a plate around the water pump. The stock blocks are a hit and miss, we have two CVOA members that have turbo'd the engine, both running boost over 20lbs, neither have had block problems. One a drag racer and the other a modified street car. The street car dyno'd close to 300HP at the wheels. These were all 2.0L sleeved engines.

Another discussion talked about making custom lower main caps that were wide enough for threaded rod to line up with the head bolt holes, thereby sandwiching the bottom end to the head. No one has put this design to test. When the blocks do split it's at the water jacket (see other two photo's below).

My autocross engine uses a long stroke crank and .070" over bore, 12.7:1CR, 2.4L. It has run hundreds of autocrosses without any problems (with the exception of when it swallowed a bolt that mounted the air cleaner!) but the duty cycle is short. It makes between 230-240HP but it rarely gets over 7500RPM, the added torque from the longer stroke makes a whale of a difference.

Dick

MyersMidget 005.jpg

MyersMidget 003.jpg

MyersMidget 002.jpg

[hammerdown7]

I should have added, the split block was from the midget, that's why he made the re-inforcing plates!

Dick

[Bzltyr]

What is the bore center of the Cosworth Vega?

[hammerdown7]

What is the bore center of the Cosworth Vega?

The engine has a 4.0" bore center, stock bore is 3.5".

Dick