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Re: Harv's Repco HighPower crossflow head thread
Posted: Fri Apr 04, 2025 2:55 pm
by sgo
Is there any oil supply to lube rollers and top of valves?
Re: Harv's Repco HighPower crossflow head thread
Posted: Fri Apr 04, 2025 6:57 pm
by Harv
From what I can see, the rollers and valve stem tips are splash-fed.
Cheers,
Harv
Re: Harv's Repco HighPower crossflow head thread
Posted: Tue May 20, 2025 6:53 am
by Harv
ARP fasteners arrived, so went to fit them. Could not get either of the exhaust or inlet shafts to bed down. Lots and lots of fit and fiddle, and paranoia that I was doing something wrong. Finally realised that the heads are hand finished, and the angles for tapping and drilling may not be exact. The results of all that fit and fiddle tell me that for my particular head:
a) for the inlets, the shaft has to be in place and then the studs screwed through it, and
b) for the exhausts, that pedestal bolts need to be started before the pedestal/rocker cover studs are started.
All good - it all fit neatly, nothing tight or binding where it shouldn't. Gave up waiting for the 1/8 NPT plugs to arrive, so took the supplied long ones and ran them partly down a die. Refit to exhaust rocker shaft, see if they are flush, then die them some more until the are. Plugs now flush and not fouling rocker cover. The outer two exhaust pedestals do slightly foul. A smear of yellow paint, rocker in place, gentle tappy tappy then check the rocker cover for where the paint is rubbed off. Die grind a little, then repeat the paint check until it no longer fouls.

- rocker cover clearance.jpg (1.12 MiB) Viewed 2165 times
Think I am about there. Fit to engine:

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Next step: pushrods.
Cheers,
Harv
Re: Harv's Repco HighPower crossflow head thread
Posted: Tue May 20, 2025 8:58 am
by Blacky
That is a thing of beauty Harv
One of our club members has one and he is making noises about selling it - its out of me budget but if he decided to move it on you will be the first bloke who knows about it

Re: Harv's Repco HighPower crossflow head thread
Posted: Tue May 20, 2025 1:26 pm
by Errol62
Come on Blacky. Need one on the yoot.
FB ute fixer upper, EK van on rotisserie
Re: Harv's Repco HighPower crossflow head thread
Posted: Tue May 20, 2025 2:23 pm
by Harv
Today, pushrods. Almost.
Knew the pushrods were too long for the rollies, so didn’t fit them when I put the head on. Need to measure, then get new ones made up. Somewhat frightened, as they are NOTHING like a normal pushrod. They need to be custom made from 1/4” silver steel rod, then heat treated. Preparing for a wallet-dectomy

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Figured I could screw the rocker adjuster out, slip in a pushrod checker, then refit the adjuster. Good in theory, not in practice - adjusters only come out downwards. Rocket gear off. I had bought a ball-end pushrod checker years ago, and managed to put it aside when I packed the shed up.

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In theory, fit the checker and rocker gear, screw the checker out (with a feeler gauge holding roller tip lash at 14 thou) and then get the new pushrods made up to that length. Slight problem: the checker I bought years ago does 9.8-10.8”… and I need about 8” for the exhaust and 6.5” for the inlet. I could cut some rod down and fit, cut, fit, cut but all that gear is now packed away with the shed, and my patience for refitting rocker gear a dozen times would grow thin. Two new checkers to suit on their way.
The next learning was that the rollers are made for 5/16” balls, and the lifter end cups are made for 1/4”. The cups are an insert fit into the standard lifter, once it has been recessed a little. If I get the cups milled to suit a 5/16” ball then I can use standard type pushrods. Lifters back out and off to have the buckets milled.

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- IMG_0198.jpeg (2.84 MiB) Viewed 2083 times
Cheers,
Harv
Re: Harv's Repco HighPower crossflow head thread
Posted: Tue May 20, 2025 4:55 pm
by Blacky
Errol62 wrote: Tue May 20, 2025 1:26 pm
Come on Blacky. Need one on the yoot.
Can't justify the cost mate - the Holden grey motor is surpassed only by the flathead frod on the wrong side of the dollars in to horsepower out equation

I could do a LOT of stuff to the 2 door with what I would spend on a Repco head for the ute......
Re: Harv's Repco HighPower crossflow head thread
Posted: Tue May 20, 2025 5:10 pm
by Harv
I can see why the red motor so quickly overtook the grey. To get 200hp out of a grey reliably costs an arm and a leg.
This exercise will be worth it in the end, but there are times when I wish I could shop a catalogue and bolt up like you can with a SBC.
Cheers,
Harv