Engine and Transmission Tech

Cadillac did this. It probably makes the engine run cooler and helps with efficiency. I'll bet you could pull some timing out with iron heads.

Paul,I think Cadillac uses the iron heads to stiffen up their lightweight block assembly. Notice they made them narrow to prevent too much weight gain(heads are only 35 lbs each).The only problem is the different expansion rate when you overheat compresses intake and head gaskets and causes leaks. Now if they cast the block in Hypertectic alloy like the pistons they would have something(closer to iron expansion rate). I think it's a tradeoff,you might get more timing with the iron heads but usually get away with more compression with aluminum heads before pinging and knocking.The biggest problem with the Cadillac is the small port sizes to maximize low end torque. You might gain 30 HP with porting but, thats about it. If it was more popular and Edelbrock or some other aftermarket company made billet aluminum heads(stiffness) with Buick V6 type ports, then you would have the perfect motor. 350lbs,450HP capable. It is going to take every trick in the book to get 350HP NA with the small ports.



Edited 1 time(s). Last edit at 08/19/2010 06:55PM by mgb260.

One of the popular car magazines ran a comparative test between identical cast and aluminum heads (to debunk or verify the urban myth) and their conclusion showed no difference in performance, no proof showing alum having an advantage of running higher CR's over cast, no heat rejection/retention advantages resulting in more power, etc.
So, the only advantage, it seems, is one of weight...say, goodbye to 50lbs.

Buick 340 heads on a rover v8......best combo so far!

Mike, Probably result of bigger ports and valves?

Yes sir.......and it keeps up with the big bore and cams of the Rover strokers.

Mike and clan, "someday" there might be TA heads and maybe you'll lose those boat anchors, lol. roverman.

Here's the article Graham mentioned:

[www.carcraft.com]

Carrying fifty pounds of dead weight costs fuel too...

Not too many manufacturers making really clever heads for sbb's and Rovers, in cast iron. I suspect even the moderate Real Steel,(aluminum) Rover head, would be and over-all upgrade from the iron 300/340 ? roverman.

From what I've heard that might be true. The 300/340 iron heads do have pretty large ports and valves though. 350's even larger. Overall, these engines suffer somewhat from limited bore size and therefore limited valve size but for street use the longer strokes and compact overall size makes up for it. The Buick guys wouldn't even consider using the aluminum 300 heads for performance as the ports are considerably smaller than the iron heads. Since the aluminum heads are also quite a bit larger than the typical Rover or BOP head, just where the Real Steel head falls in the spectrum is a question but I'd expect it to be somewhere a bit below the iron heads. I could be wrong. But I've yet to see Real Steel heads on an engine in the Buick forums. If it's better it should be popular.

JB

In my personal experience, trying to get heads from Real Steel or parts remotely on-time(Wildcat), is like getting the long over-due heads from TA., you get on a waiting list and then you don't hear from them. roverman.

To their credit though, TA does have a history of following through. (Take their aluminum big block for example) And once they have a new product on the market and actually delivered they don't seem to have much trouble keeping up with orders. It is true that their biggest interest has always been with the big block engine and then secondly with the V6 (even though the alloy V6 block was first). A great part of where they are now was simply inherited from Kenne-Bell. But Mike Jr. owns a small block car and has long been the SBB enthusiast's direct line to management. In truth he is probably as much the motivating factor behind the new heads as anyone. The important thing to notice is that although slow at times, development work continues to progress. They have had teething problems with it. Their moldmaker retired in the middle of the project or some such nonsense, and the economic downturn has hit them fairly hard. They are a family owned company much like our own favorite vendors, and despite being a bit larger have the same sort of issues to deal with.

So if you are really wanting a set of their promised heads I wouldn't worry that it won't happen. They are far enough along in the process now that I doubt they will cancel the project. The first run may be spoken for and you may have to wait for the second or even third run, but once they start to go out the door I'd expect their production will catch up real quick. My biggest concern is their possible departure from their traditional pricing structure.

JB

Mark MG Bloke from the V8 Owners Forum has had very good results with the Merlin Heads.

Follow his thread from here.

[www.v8forum.co.uk]

Kevin.

Jim and clan, I read with great interest in the V8 Buick Forum, how a stock block/head,(re-worked) 350 sbb pulled 1,021 flywheel hp. on race gas!, and lived to tell the story @ 20lbs. manifold ! They plan to go to 24lbs NEXT! Golly, what if someone were to put 350 heads on a Rover? I'm considering a Buick V6 reported to make 2.45hp. per inch, all motor/gas. This may be a good year for Buick/Rover. roverman.

Kevin, thanks for the link. Quite impressive.

It's questionable whether there would be any advantage in using 350 heads over 340 heads. I've not seen any reliable data indicating that it is, other than the factory horsepower specs for the two engines and as we know they played games with those specs during the years involved. We have no definitive info on Buick's motivations in developing the 350, or their reasons for changing the port layout, which was the biggest single difference in the two motors. The 350 ports may be a bit larger, I can't say, but I doubt there is any difference in the maximum valve size beyond the .050" bore increase. But it could be done, possibly with nothing more than a custom ground cam. Valve shrouding would clearly be an issue with the smaller bore.

The 1000+hp 350 was truly an impressive achievement. Hard to say what a 340 on 22lbs of boost from intercooled twin turbos would do, but any way you look at it that was impressive. I don't think you could fit all that in a stock appearing MGB though.

One other thought. The V6 Buick engine uses the earlier port layout and has also produced over 1000 hp in race trim using aftermarket heads and boost with two fewer cylinders. So it's doubtful that the later port layout has any inherent advantage other than potentially better flow in stock trim.

JB

Jim and clan, Dan White is claiming 1,800 hp with a Stage II V6 ! Will wonders never cease ? I'll be pleased to have 460+ out of mine. roverman.



Edited 1 time(s). Last edit at 08/27/2010 07:03PM by roverman.