37 replies to this topic

[xbgs351]

How many were built?
How many are left?
What were the technical specifications?
What was the output?
What was different about this v8 compared to the other pushrod v8's that raced in F5000?

[Ray Bell]

It was based on the Holden 308 engine...

Repco aimed more for torque than power, I gather.

[xbgs351]

I have found some information on these motors in 'Motor Racing the Australian Way'. Here is a brief summary:


- The engine retained the 308's stroke of 3 1/16", but instead of a 4" bore it was underbored to 3.960"

- Standard 2-plane 308 crankshaft was used with different oil passages & the webs were increased in section.

- 4 bolt steel intermediate mains.

- Repco 770 Trimetal bearings.

- 308 heads, with oversized valves, bronze valve guides and porting.

- Light needle-roller bearing rockers on eccentric spindles for adjustability.

- Solid tappets, running in guides placed in the original lifter bores.

- Lucas petrol injection with plate throttles and independent runners.

- Dry sumped, with a 3 bank pump.

- Modified 308 rocker covers with oil drain tubes at each end.

- Initially 440 bhp @ 6800 rpm, with a permissable 7500 rpm. Later 460 bhp (as of 1972).

[cosworth bdg]

The engine was designed by Repco engineers of the time, the late Phil Irving and Brian Heard. The last of the 90 deg crank engines had 495 BHP @ 7000 rpm while the flat plane crank engine had 520 BHP @ 7100 RPM.............This engine had a lot of Phil Irvings idea's incorporated into it........ see Repco Technical News & Developments , August, 1970--No--3......... They were not designed to be changed by Rocket Scientists.............

[cosworth bdg]

Whom ever has one in their possession and running it in F5000 Historics has a real piece of contempory Australian motorsport history.........

[xbgs351]

Originally posted by cosworth bdg
The engine was designed by Repco engineers of the time, the late Phil Irving and Brian Heard. The last of the 90 deg crank engines had 495 BHP @ 7000 rpm while the flat plane crank engine had 520 BHP @ 7100 RPM.............This engine had a lot of Phil Irvings idea's incorporated into it........ see Repco Technical News & Developments , August, 1970--No--3......... They were not designed to be changed by Rocket Scientists.............

Compared to 525 hp @ 7500 rpm quoted in Modern Motor for the sbc in the Elfin MR8, the Repco Holden looks to be competitive. Given that the Repco Holden Motor was lighter than the sbc, why wasn't it a more popular engine choice in F5000?

[cosworth bdg]

The only people that can answer that question truethfully is the competitors of the area----------------

[Ray Bell]

John McCormack is adamant that the Repco Holden engine was better than the Chevs he used them against...

I don't think weight was much of a factor, however. The torque band was.

[cosworth bdg]

The TORQUE band of the REPCO was far supperior to the CHEV in F5000, but as Repco soon found out ,horsepower sells engines , not torque-----------------

[Peter Brennan]

A pic for your interest.Merry Christmas to all.Pete

[cosworth bdg]

A good picture Peter, A Merry Christmas to all, Regards Peter N .....

[xbgs351]

Matich A50 at Phillip Island 2007

[Leo D]

It was great to see the Matich A50 back on the road after Sandown....

I was hoping to see the Chris Hocking Matich A53 there as well..... Does anybody know the status of that car at the moment?..... Can I assume that it's going to be Repco powered?

[Ray Bell]

The only option is Ford, isn't it?

And who'd want to go that way?

[275 GTB-4]

Originally posted by Ray Bell
John McCormack is adamant that the Repco Holden engine was better than the Chevs he used them against...

I don't think weight was much of a factor, however. The torque band was.

Isn't the Slako 308 based machine still in Perth

[Ray Bell]

I have no idea... I think that perhaps three of the Matich chassis could technically be built up as A53s, one would have the right to wear a Ford engine if anyone were silly enough to go that way.

[Leo D]

Originally posted by Ray Bell
The only option is Ford, isn't it?

I don't remember seeing it ever run with Ford power Ray, although I do recall that John Goss was working on one.
Did he ever actually race it with Ford power, or did they just try it testing and revert back to the Repco unit to race with?

[Ray Bell]

I'm sure they tested it and they may have once practised with it at Oran Park...

[D-Type]

Point of clarification: i always understood that British F5000 and US Formula A were based on production engines(to keep costs manageable). T his Repco-Holden looks to be a purpose built engine, albiet production-based. Did Australian F5000 allow bespoke engines?

[Ray Bell]

Same rules all over, basically...

Production head and block, internals free, carburetion etc free... except either England or America didn't allow fuel injection for a few years. I can never remember which.

Where the Repco-Holden sort of set a standard was in its professional build and appearance.

[normbeechey]

I remember that Goss ran with the Ford heads at Sandown at least once. Was it Ford heads on a Chev or Holden block, not a Ford block? I'm not big on engines, but I seem to recall that sort of thing can be done.

[cosworth bdg]

Where the Repco-Holden sort of set a standard was in its professional build and appearance.

[Ray Bell]

Originally posted by normbeechey
I remember that Goss ran with the Ford heads at Sandown at least once. Was it Ford heads on a Chev or Holden block, not a Ford block? I'm not big on engines, but I seem to recall that sort of thing can be done.

If that's right, it wouldn't surprise me... but it was a wholly-Ford engine. I recall that Peter Molloy was in some way involved in it all and he complained about the engine weight.

[seldo]

Originally posted by Ray Bell


If that's right, it wouldn't surprise me... but it was a wholly-Ford engine. I recall that Peter Molloy was in some way involved in it all and he complained about the engine weight.

That figures Ray since Peter was a bit obsessed with the weight factor. I recall that he was want to machine-off all unwanted or un-needed lugs, brackets, flanges and casting excesses.

[Ray Bell]

He claimed that the Ford weighed 100lbs more than the Holden, David...

That's a lot of brackets!

[cosworth bdg]

Originally posted by Ray Bell
He claimed that the Ford weighed 100lbs more than the Holden, David...

That's a lot of brackets!

The engines that were considered too heavy for F50000 were the Ford and Chrysler LA engines even though they may have been more powerfull ???.........

[Bob Riebe]

I am a little bit confused here, just which Ford engine are you speaking of?

The Windsor Ford is lighter than a Chevy in both short and tall deck versions.
The short deck is a good deal lighter.
Bob

[Catalina Park]

I wonder if it was the Cleveland block? Goss was running them in his Falcons at the time. The heads would have been good but the block...... :

[Ray Bell]

Yeah, Australian made Cleveland 302...

And it wasn't a Chev that it was replacing, it was a Holden.

[cosworth bdg]

Are you sure Goss did not use the Windsor block with cleveland cyl heads...

[seldo]

Originally posted by cosworth bdg
Are you sure Goss did not use the Windsor block with cleveland cyl heads...

...Hmmm....That sure rings a bell...

[Catalina Park]

Originally posted by cosworth bdg
Are you sure Goss did not use the Windsor block with cleveland cyl heads...

They said it was unreliable, underpowered and overweight so I would assume that they used the Cleveland block to reach all those targets.

[cosworth bdg]

Originally posted by Catalina Park
They said it was unreliable, underpowered and overweight so I would assume that they used the Cleveland block to reach all those targets.

I can belive what you say...

[seldo]

Originally posted by Catalina Park
They said it was unreliable, underpowered and overweight so I would assume that they used the Cleveland block to reach all those targets.

True enough - who can argue with the logic...;)

[xbgs351]

Originally posted by seldo

True enough - who can argue with the logic...;)

The Cleveland block weighs practically the same as tall block Windsor, which is heavier than the sbc, Holden v8 and 302w. The difference in weight between the Cleveland & Tall block Windsor lies in the cylinder heads.

2V Cleveland cylinder heads have a similar port volume and superior flowrates than the 4V SBC, Holden and Windsor offerings. The 4V Cleveland heads have far larger and superior flowrates again. Hence a Cleveland headed motor in 2V or 4V form should be able to produce as much or more power than a five litre Holden V8 or SBC. The Clevelands mixed it up with bigblocks in Nascar, so I don't see why they should have had a power disadvantage to other smallblocks.

In the 70's Cleveland powered touring cars had reliability problems that were predominately related to the oiling system as mechanically the Clevelands are very strong motors. Most of the problems were because the touring cars couldn't run dry sumps, something that doesn't apply to F5000. In addition the Cleveland oiling system feeds one bank of lifters and the mains from the same oil gallery, which can cause problems if the lifter/bore clearance is excessive. This oil gallery design was rather common on other American V8s of the time, but they had more restrictive cylinder heads that wouldn't support as high revs as the Clevelands could. This oiling problem can easily be negated with restrictors and by bushing the lifter bores.

A 302 Cleveland would not make a good engine for F5000, soley because of it's weight. A Boss 302 (essentially a 302W with 4V Cleveland heads) or a 302 Windsor with 2V Cleveland heads should have had the potential to be competitive. As the class is run now, with all runners using aftermarket alloy cyclinder heads, a 302W with Cleveland style Cylinder Head Inovations heads should be lighter than the Pro Cylinder headed SBC or Bennet headed Holdens and it should have a significant power and torque advantage over them as well.

[Bob Riebe]

Originally posted by xbgs351


The Cleveland block weighs practically the same as tall block Windsor, which is heavier than the sbc, Holden v8 and 302w. The difference in weight between the Cleveland & Tall block Windsor lies in the cylinder heads.

2V Cleveland cylinder heads have a similar port volume and superior flowrates than the 4V SBC, Holden and Windsor offerings. The 4V Cleveland heads have far larger and superior flowrates again. Hence a Cleveland headed motor in 2V or 4V form should be able to produce as much or more power than a five litre Holden V8 or SBC. The Clevelands mixed it up with bigblocks in Nascar, so I don't see why they should have had a power disadvantage to other smallblocks.

In the 70's Cleveland powered touring cars had reliability problems that were predominately related to the oiling system as mechanically the Clevelands are very strong motors. Most of the problems were because the touring cars couldn't run dry sumps, something that doesn't apply to F5000. In addition the Cleveland oiling system feeds one bank of lifters and the mains from the same oil gallery, which can cause problems if the lifter/bore clearance is excessive. This oil gallery design was rather common on other American V8s of the time, but they had more restrictive cylinder heads that wouldn't support as high revs as the Clevelands could. This oiling problem can easily be negated with restrictors and by bushing the lifter bores.

A 302 Cleveland would not make a good engine for F5000, soley because of it's weight. A Boss 302 (essentially a 302W with 4V Cleveland heads) or a 302 Windsor with 2V Cleveland heads should have had the potential to be competitive. As the class is run now, with all runners using aftermarket alloy cyclinder heads, a 302W with Cleveland style Cylinder Head Inovations heads should be lighter than the Pro Cylinder headed SBC or Bennet headed Holdens and it should have a significant power and torque advantage over them as well.

It is hard to get numbers as different sources, measure in different manners, but the most common weights for US engines are:

Chevy small block --575 lbs., which is why a ZL-1 BB--550 lbs, was said to weight 20 lbs less than an iron small block.

Ford:
Small block--460 lbs
Boss 302--500 lbs
351 w-- 510 lbs
351 c -- 550 lbs

AMC:
Second design--540 lbs



A big difference on the Cleveland was the non-removable timing chain area which could be switched for an alloy one on the Windsor.

Follmer one two races with a Boss 302 on carbs in the US.

Bob

[xbgs351]

Originally posted by Bob Riebe


It is hard to get numbers as different sources, measure in different manners, but the most common weights for US engines are:

Chevy small block --575 lbs., which is why a ZL-1 BB--550 lbs, was said to weight 20 lbs less than an iron small block.

Ford:
Small block--460 lbs
Boss 302--500 lbs
351 w-- 510 lbs
351 c -- 550 lbs

AMC:
Second design--540 lbs



A big difference on the Cleveland was the non-removable timing chain area which could be switched for an alloy one on the Windsor.

Follmer one two races with a Boss 302 on carbs in the US.

Bob

See how the difference between the 302W and 302 Boss is 40lb, when the main difference between the two motors is the heads. The difference between the 351W and 351C is also 40lb.

[Bob Riebe]

Originally posted by xbgs351


See how the difference between the 302W and 302 Boss is 40lb, when the main difference between the two motors is the heads. The difference between the 351W and 351C is also 40lb.

The Boss used the racing block which was a great deal sturdier than any standard small block, due to extra metal in critical areas.

That eliminated the stud girdle that Gurney used on his earlier engines.

The heads probably did add ten pounds.

Bob