Hi Sunbeam Alpine swappers. Greg Fast here, I'm the guy with the Chevy Orange 2.9 Jim shows in the first post. I wrote Jim a lengthy rambling history about the engine, and rather than repost it I think the best idea is for me to tighten the editing and give a bit of background.
The engine was being developed for SCCA GT-2 road racing in a 70's Capri. It is based on the 2.9 Cologne- the block shown was from a Merkur Scorpio, with World S/R heads an acceptable alternative in the GCR's. The Ranger/ Bronco II are essntially the same engine, and could be used in place of the Scorpio engine. Unfortunately, the plan was screwed up by letting in a bunch of faster cars in, and it looked like the engine became uncompetitive before we got finished. The other hitch- World stopped producing 2.9 heads. My co-conspirator on this deal was about to buy the tooling (they were offering it for fractions of cents on the dollar), but I talked him out of it. We worked with a head guy and ended up with some pretty decent numbers, never got the engine on a dyno. This particular engine has a .530 cam, smith bros pushrods, re-ratio'd stock rockers
Something that may be of interest with this engine- we used 5.4" rods from a 331 (?) or maybe 347 SBF stroker kit, along with the Clevite now Mahle SBF racing bearing for the rods. Had to cut the crank cheeks a little, and crank had to have an ultra precision grind, and there was like a .001 difference in diameter (most grinder will just take off .010, but these bearings were only available in stock SBF size. Pistons are Diamond forgings, had to send a plaster casting of the head to get the compression ratio desired- and even then, couldn't get as high as we wanted.
Chain driven cam does rotate opposite the gear driven 2.6 and 2.8, there is a specific distributor drive gear that combined with the cut of the drive gear on the cam spin the 2.6 & 2.8 distributors the same direction as a 2.6/2.8. So the advance mechanism in the 2.6/2.8 distributor works. At one point I bought all the 2.9 distibutor drive gears Rock Auto listed, they may have refilled the supply chain. I recall there was a difference in the distributor shaft diameters- I think we had to shim the 2.8 dizzy for the larger bore of the 2.9 dizzy drive gear. I prefer the reliability of the Duraspark. Another spark related issue is the 2.9 oil pump driveshaft uses TORKS type spline to drive the oil pump, while the 2.8 uses a traditional Hex shaped shaft. The easy button was to grind down the distributor side of the shaft to a hex shape, and let the oil pump use the existing TORKS shape. I forget if we needed to add weld filler to the distributor TORKS to grind own and make the hex happen.
There is another solution to this- some German guys are cutting the distributor shaft apart and grafting a 2.9 lower shaft by the gear to the 2..6/2.8 upper shaft and pinning the deal together. They were workig with Bosch distributors, I ended up pulling what remaining hair I have out on the process, I recommend not taking this path. The pin holes do not alighn, it becomes a bigger problem than what it's worth.
The other issue was carb intake. The US and European 2.6 & 2.8 use a 5 port head, with intake spacing roughly the same as the 2.9. I used an OFFY 2.6, we had to relocate a couple of the manifold hold down bolt locations, but it was basically then just port matching. Thinking the early 2.6 and European 2.8 could be configured similarly. US 2.8 has irregularly spaced intake ports, it's a fatal issue.
Read comments on the 2.9 V6 Info thread- have some comments-
If I remember correctly, the 2.9 and 4.0 set the distributor/oil pump drive directly on the block, and location is unaffected by deck height. The distributor does not pass through the intake.
I would not recommend using a 2.9 distributor gear for a 4.0- the 4.0 uses a roller tappet cam, and a steel cam core used with rollers has proven problematic in other engine types. Simple solution is to use the 4.0 gear.
We had larger diameter intake and same diameter exhausts made in stainless, & Ti spring retainers made
The 2.6 and European 2.8's use the 5 port head, with port spacing very similar to the 2.9. I'm thinking they could be modified to work. The US 2.8 used a 6 port head that's not even close.
My co-conspirator still has a bunch of killer intake and exhaust valves, Ti valve spring retainers, and a bunch of miscellanea if anyone is interested.
It was a fun project that took us a couple years. By the time we were close the motor would never stand a chance. Makes a nice base for a coffee table...
One intake option for the 2.9 is the Ford Scorpio FI intake- it looks great. I've been able to purchase a few of them from ebay UK, and actually found a guy parting out a Scorpio in the US and snagged his.
Mo' later
