Cosworth Vega

[Fheckro]

Does anyone know if there is an iron block with the same cylinder spacing as the aluminum Vega Cosworth block?
 

Fred

[gkabbt]

Fred,

Don't know if this will help or not but, dusting off the cobwebs in my mind, I remember thet Chevrolet made a "special heavy duty" off road block for racing purposes. Unfortunately, I don't remember if it was aluminum or iron. Also, the Cosworth cranks were destroked down from 140 CI to 122 CI.
Most Vega 2300 folks had the aluminum block bored and iron liners installed.....made them 1/2 way decent engines.

Hope this helps,
Gregg


Edit:
Just found this link for Frank Sloan's Bonneville G/PRO 929 Cosworth Vega:
http://www.streetlegaltv.com/news/frank-sloans-cosworth-vega-runs-at-bonneville/
Try to get in touch and maybe he can provide the info your looking for.

HTH

[jacksoni]

The Heavy duty Cosworth Vega was dimensionally identical to the stock block with some reinforcing ribs. Bore centers IIRC were 4" with the stock 3.5" bore. Frank had/has at least 3 HD blocks plus a stock one that had been reinforced that I sold him a number of years ago. Mine had heavy 1/2" thick top sleeves that were machined to interference fit with the outside of the block to reinforce the upper part of the free standing bores. In  addition I had made a 3/4" thick main girdle that tied the bottom together. I know the midget racers had some trouble with the head and upper part of the block cracking 360* and separating from the crank etc. They reinforced this with turnbuckles from the head down to the main girdle or similar to provide additional compression top to bottom. I never broke a block except when no oil pressure, a heavy foot and a lot of detonation spun a bearing and put a rod through the side of the block at 260mph. Small fire ensued. 

None of this answers your main question of course. I am not aware of one (Iron block). The GM Iron duke and iterations have 4.4 bore spacing same as SBC. There are other 4 valve engines out there now and might be a better starting point. Quad 4 of course and they have been raced but were no stronger really, took lot of work to live, similar to what I did above and made no more power. The thing in the Olds Aerotech car was a quad 4 in name only. However, the 215 Buick/Olds V8 does have same spacing I think and for long time I thought about trying to make that adaptation. Beyond my machining capabilities. And though the CV head was decent- mine flowed about 253 at .400 lift, current 4 valve heads- Honda specifically- will blow it in the weeds.

[CTX-SLPR]

Small Buicks (V6 included) have a 4.24in bore spacing.  I think the Pontiac Astre had a 2.5L iron block version of the Vega I4 in later years but am not completely sure.  Wonder what the bore spacing on a Northstar is?

[jacksoni]

All the 2.5L GM engines from that era were the Iron Duke-Tech IV series that were similar but not identical to the earlier 4 cyl that was essentially the inline 6 with 2 cylinders cut off that was in the early 60's vintage cars. Parts from those engines do not interchange. Both were raced in Midgets and other circle track series and GM did have a Super Duty Pontiac program for some time that used the 2.5L engine and made a lot of performance parts. Some are still out there but mostly other special built engines (Fontana etc) are currently used in midget racing. They were iron block and with SBC bore spacing. This includes the Astre 2.5 engine. This was the base GM 4 Cyl engine until about 1990. They were not iron block vegas. A Northstar V8 aluminum block does have 4" bore spacing but is already a DOHC 4 valve so trying to adapt a CV head to it wouldn't really make a lot of sense. Just go buy an Indy Aurora engine. 

[Fheckro]

Thanks all for the input. My friend and crew chief Dennis Anderson wants to run his Cosworth in CPRO which could be fun; I think that motor has a lot of unused potential. So i guess it's find an HD block or switch plans. I don't know how much money he is willing to commit so that's why i was hoping to find a "cousin" block or something. I  have heard the HD blocks are kind of pricy now days. Still it would be cool to see it run like it was supposed to. 

Fred

[Ken Yooper]

http://www.teamshelby.com/forums/index.php/topic/41114-a-fifth-chrysler-16v-22-head/

If my memory is right, Neons had a 96 mm bore center - close, but not exactly four inches.  They also used a few different DOHC cylinder heads, one of which might have been a Cosworth - they used a Lotus piece for sure and during that time frame, Lotus had some ties with GM.    

Hope this helps a little

KenB

[jacksoni]

Thanks all for the input. My friend and crew chief Dennis Anderson wants to run his Cosworth in CPRO which could be fun; I think that motor has a lot of unused potential. So i guess it's find an HD block or switch plans. I don't know how much money he is willing to commit so that's why i was hoping to find a "cousin" block or something. I  have heard the HD blocks are kind of pricy now days. Still it would be cool to see it run like it was supposed to. 

Fred

Since they have now opened up Classic to smaller than F motors, sounds like a plan. According to the website posted about Frank Sloans car he got 260 out of it. Most I ever heard of was about 270. I might still have some dyno sheets from McLaren showing about that on MeOH. In the past people talked about CV heads getting ported beyond what GM suggested in the Chevy Power book (pretty much bore the intakes to 1.1" (IIRC- would have to go look it up). It was said they became dogs with that. I suspect modern porting knowledge and a max effort Bonneville car might work ok but low rpm (never a strong suit) and midrange may suffer. Sonny Rossi also ran a CV in his '23 T roadster. Those two folks, Sonny and Frank, might be source for parts/ideas. You have to remember though, if your friend has a nice stock Cosworth, you will have to cut it up pretty much to make it legal for Bonneville. If it is already a race car is easier to do that. Not trying to disuade you. For REference in 1979 with a modestly modified engine (WEBERS, 12.5-1 GM 12.5-1 pistons and the Crane " GM "long track" cams running G altered I went 135. Blew up a lot of stuff that year, my first. The next year with a Hilborn on it went 138 and then with Methanol 143+. I know Frank spent a lot of time working his way from low 140"s up to his 156 G/Pro time. That has now been bumped to 174 as you probably know. But you will be on an open record- don't know if there are minimums though. Anyway, lots of luck. Should be fun- it almost always is-even if you blow up stuff.   I'll be happy to help any way I can.

[Stan Back]

Jack,

No minimums at Bonneville.  There are minimums for the 2-Club, but maybe this doesn't apply.

Stan

[jacksoni]

Jack,

No minimums at Bonneville.  There are minimums for the 2-Club, but maybe this doesn't apply.

Stan

Crikey, I knew that!   Sorry was a bit confused there. Been so long since have seen classes with no record. But had forgotten Dave Freiburger and Keith Turk with their 2 piston big block running F/BG something at 35mph when they fried their motor. I think this was one where the push truck got a timing slip- and having been accused of that, I feel ok poking bit of fun at them. 

[Fheckro]

Since they have now opened up Classic to smaller than F motors, sounds like a plan. According to the website posted about Frank Sloans car he got 260 out of it. Most I ever heard of was about 270. I might still have some dyno sheets from McLaren showing about that on MeOH. In the past people talked about CV heads getting ported beyond what GM suggested in the Chevy Power book (pretty much bore the intakes to 1.1" (IIRC- would have to go look it up). It was said they became dogs with that. I suspect modern porting knowledge and a max effort Bonneville car might work ok but low rpm (never a strong suit) and midrange may suffer. Sonny Rossi also ran a CV in his '23 T roadster. Those two folks, Sonny and Frank, might be source for parts/ideas. You have to remember though, if your friend has a nice stock Cosworth, you will have to cut it up pretty much to make it legal for Bonneville. If it is already a race car is easier to do that. Not trying to disuade you. For REference in 1979 with a modestly modified engine (WEBERS, 12.5-1 GM 12.5-1 pistons and the Crane " GM "long track" cams running G altered I went 135. Blew up a lot of stuff that year, my first. The next year with a Hilborn on it went 138 and then with Methanol 143+. I know Frank spent a lot of time working his way from low 140"s up to his 156 G/Pro time. That has now been bumped to 174 as you probably know. But you will be on an open record- don't know if there are minimums though. Anyway, lots of luck. Should be fun- it almost always is-even if you blow up stuff.  I'll be happy to help any way I can.

I hear ya about the nice stock Cosworth. And his is nice in my opinion. Personally I wouldn't do it but he has been bitten by the bug. We have a line on another Cosworth "basket case" and i am working on him (i'd buy it if i wasn't sucked dry by my monza). Some questions that i need to get answers to are will Bonneville accept aftermarket FI (like mega squirt) on a classic like the Vega that came stock with D-Jettronic stuff and how close does the motor bottom end have to be to original to run in CPRO?  I think with today's technology there is more performance in that little hot rod. Cam wise as well as port flow. I was thinking 14.5:1 would be a good starting CR. I would like to talk to Jesel or someone like him and see what could be done in the cam dept.

All in all I just like the darn thing. nothing else from the low buck 70s compares. Its just a crying shame that marketing and legal de-clawed the poor beast. Sounds like you had a lot of fun thrashing on of these. I think we would have a super adventure campaigning it. Maybe soon ... maybe me... who knows.

Fred

[jacksoni]

Couple of things. Other than the engine, there is no difference in a stock Vega and the Cosworth other than paint, decals and wheels. They don't count. Find an ex 75-76 Vega race car (cage must be legal but in G you have some leeway in that a 1.5x095 cage is legal though folks will suggest you put a full up one in it (1.625x.125) in it if you have to start from scratch)  and put your CV engine in it. Thats legal ( all my opinion of course but I think am correct here). You cannot use some other block with CV head on it. That would be an engine swap and put you in GC, Alt etc. You can put the CV head on any Vega block, no problem and the stock Vega and CV blocks were the same as far as I know. HD model discussed previously. A stock block can be modified for strength as I mentioned. You need CV head gasket or if you do the o-ring to seal the cylinders deal, you need an oil restrictor in the block. You CANNOT use an after market EFI like megasquirt etc, It must be OEM.  In fact, if was not that the car came with EFI, that would not be legal at all. However, You can run mechanical FI or Carbs. In my opinion, Jesel will be of no help. Finding cams will be issue, certainly new grinds. Couple years ago I had email conversation with Chase Knight who is the main guy at Crane Cams. He had ground several for me. He said they still had some cores. I expect that is your only avenue other than a custom set of cores. You can get cores made but the cost goes way up. Also, if you or your friend are not familiar with the CVOA ( Cosworth Owners Assoc) it was and may still be a source for hard to find stuff like gaskets, shims etc ( I used some VW shims cut down to CV diameter). I can put you in touch with guy I know there who would be a good resource about CVOA and what is available these days.

Also, if you do this and lean on it as you are suggesting, dry sump it. The stock oil pump is not good enough if you are making power and RPMs. I got away with it for quite a while until a pump just wasn't right and it cost me a motor and as i mentioned above, a fire at 260 is no fun though my extinguishers worked fine and I barely had any burned wires. But I don't recommend it. "nuff said about that.

The above applies if you want to run Production. If you move to GC or ALT, things are more free and for instance you could use the megasquirt.

Let me know if you have any questions or want that CVOA contact. If I think of anything else will sing out.