Mopar Muscle Association UK

Engines that were Factory built but not necessarily sold to the public....and/or put into road vehicles...From 1960>

anyone get it right 1st time???

That's a tricky one as the factories tended to lie about HP either upwards or downwards depending on who they were trying to fool. Assuming we are talking American, I would think it's one of the all ally ZL1 style big block Chevy's at around 600hp.

How do you know what the engines ACTUALLY produced?

For example, the 426 Hemi was quoted at 425bhp. People in the know think it made 500bhp but was quoted low due to insurance premiums and concern about regulation.

On the other hand, I am sure that some manufacturers over-quoted the output in order to help sales.

I think we will never really know.

Another example of quoted Bhp was the "new" 528bhp Chrysler crate engines. Mopar quoted over 500bhp and when disappointed people Dyno'ed samples they found motors were making just over 250bhp. Would you be gutted or what? - tapered and eliptical bores - the whole works...........

Blimey Blue SNAP!
It must have been a race to hit the "Enter" button!!!

Also I think you are probably on the money with the ZL1 COPO motor when everything is taken into account.........

American yes Blue...not yet there boys, I thought it was the ZL1 as well.........there's one out there that beats them all hands down......
a clue is that it was never put into a production car.....only 50 were sold which went into Drag Cars.

It was quoted as unstreetable....was built to rival a certain well known motor........that should give it away?.....

Is it the Ford 427 sohc 'cammer' engine?

SPOT ON MATE

Ford Made 50...it revved to 7500rpm, made 616hp with 1 carb and 657hp with twins....absolutely awesome.....

not streetable huh

Did the Boss 429 semi hemi evolve from that engine then Les or was it the other way round?
I remember reading up on it years ago, awesome piece of engineering, can't see why it wasnt street able tho, even Lintiac had produced an aluminium headed obv on the Sprint 6 that made 50% more power than a conventional 6, so production tech was definitely there?

I would imagine as that cammer was built in 1965 to rival the 426 Hemi, the BOSS 429 evolved from that, guess they thought they'd have another go at it but make it less extreme?....tbh that was a flop as well really although at least they got it in production.

They reckoned that it was unsuitable for the street because of the massive HP which it made at 7500rpm, unheard of in 1965 for a road car...can't see it myself, it was the HP wars then, we'll never know the real reason.....but what a master piece....

Wonder if our beloved Hemi would still have the magic it still has today if that Cammer managed to make it to the streets in numbers?

Blimey !!!
A good point Les. The 426 has always been a god to me from a young age at the pod ! And then I learn this !!!!................................................................nah. Praise the hemi

Gary

What exactly differentiates the race and street Hemis? Is it just a solid cam and compression?

The original street Hemi's had solid cams.

No roller tipped rockers, wore like a bugger - constant adjustment needed, hence the shift to hydraulic in a weak attempt to stem the wear.

The geometry is pretty pants on a stock one.........

Don't think the cammer or the Boss 429 ever really rivalled the Hemi's dominance. If some of the other Ford hi performance engines are anything to go by I would imagine the cammer had huge ports and valves meaning it made bugger all low and mid range power which is probably where the "unstreetable" tag comes from. I know for sure Holman & Moody made port restrictors for the Boss 429 to try and give it some street manners.