Aftermarket conrods with 24mm pin

[fastback]

I have race rods made here in the UK by Farndon, they have the drawings for mine on file but they too need case and cam clearancing work for the big end bolts, they are cosworth spec, they will quote you, but best be seated when they do so,

nice BBB.
are these offset small end as the stock ones?
and are these in the carillo price range?

[AMBROSIA]

A wee guide and lots of choices , valve seat work is the key, Wassers respond well to valve sinking, the downside is it costs compression pressure, first off, they are tight on installed valve spring height, roughly 1.4", the performance way to a win win fix is to sink the valve .080", I won't go onto a porting and seat flow waffle, but it's the key to big gains from seat profiling for out and out motors, sinking also fixes the spring height problem back to a workable T1 spec enabling T1 hardware and geometry to work, it also gains piston to valve clearance, but all the chamber matching and profiling costs a deal of compression, it just costs cash to gain it back, another story,, A compromise is to cut the spring seats or use a higher spring height retainer such as bergs 281A, these gain .150" spring installed height.
Conversion valve guides are available for the exhausts at 8mm stem, but again, light stainless valves cost compression as they are dish heads, mine are made by Paul Ivey and trim off stock 20 odd grams tho much bigger, but the stockers can still flow 170hp ,but need some valve spring pressure to go over 6000 rpm. I use 175 lb installed and 285 nose for 7000rpm with stock jobs. One thing is the Febi lifters are heavy and need shorter push rods, a solid conversion on stock hydros is my way if you don't need a T1 lifter conversion, lighter than solid T4 and better oiling, and the stock length steel p/rods can stay, they are fine at 6000 rpm.

Very interesting.

The spring height is going to be an issue I suspect as the cam/lifter combo will be just shy of .500".
TBH I specifically selected the combo as I wanted to avoid further complications with clearances.
Regarding valve sinking, this clearly gives me big headaches as you say, so I would rather avoid it if possible.
I'm awaiting Jim's verdict on the heads and will decide then.
I like the look of the berg retainers plus i'm keen to lose some unnecessary weight here.
Thanks for the heads up on Paul Ivey, I will pass that along but if I can make stocker's work and retain the compression ratio I feel this would be more suitable for my goal.
The issue I have had with stock valves is tip damage due to repeated hydro bleed downs, but this will be resolved using solids.
James offers some HD aluminum push rods that will expand and keep the valve train quiet when hot unlike the stock steel ones will.
Converting the hydro lifters has been mentioned on this site, probably by bbb and as I have a set of new ones perhaps this is something to investigate.

Thanks again bbb.

[buildabiggerboxer]

I have race rods made here in the UK by Farndon, they have the drawings for mine on file but they too need case and cam clearancing work for the big end bolts, they are cosworth spec, they will quote you, but best be seated when they do so,

nice BBB.
are these offset small end as the stock ones?
and are these in the carillo price range?

Hey Fastback, how's that mad bus?? Good I hope,
The rods have no offset, my last set were certainly Carrillo money, maybe a bit more these days, the only downer is the weight, I've moved to CB race rods for my carb motors. Regards,BBB.

[fastback]

thx BBB
the bus is parked for the winter.
considering building up my "big" wbx again and would like som offset aftermarket rod's at a fair price

[pocketrocket]

Anyone wanting a set of aftermarket rods with 24mm pins. I do them. They have to be set up on a fixture bored, stock 021 bushings machined installed with the correct press fit, then machined and honed to the 24mm size. These are the rods I do for all the engines I build now. I had a rod set done by a So-cal company a few years back two of the rod bushings came loose. After that I went to work on making a fixture and doing them in house to my specs. Rocky

[AMBROSIA]

Picked my conrod's today.
Scat I beam's machined, bushed and honed to 24mm.


Happy with these!

[tencentlife]

Make sure you check for straightness and twist and bend them to correct, Scat doesn't check that after this mod and the pins are usually tilted, sometimes a lot.

[Piledriver]

Make sure you check for straightness and twist and bend them to correct, Scat doesn't check that after this mod and the pins are usually tilted, sometimes a lot.

Really? I figured they would do them on a mill. Surprising.

[AMBROSIA]

These where machined in the UK, supplied by scat in T1 spec.
I specifically went with a seasoned pro for this job and he is one of only two guys I would trust this side of the pond.
I presume some kind of jig would be required to check for squareness in a sensible measuring range.

[tencentlife]

Well if they're responsible they will check after the work and straighten as needed. Not all machinists are that responsible, I've found. Scat didn't bother. Out of the box their production work is great, but the small-end mods were done stateside and they need better jigging and followup. Even with a great jig they still need to be checked because tilt can be introduced during honing. I do my own now, came up with a really good jig and process, never more than .002" tilt across the width of the bushing. I straighten and twist if needed to get that within .001" in both directions. If I were you I would ask if they were checked and to what tolerance, it's easy to straighten them if needed.

I check tilt on my lathe with a dial indicator, twist is easy on a surface plate with 1-2-3 blocks.

As always, trust, but verify. You're the one who has to live with the results.

[buildabiggerboxer]

The rod fixture is the key, a bad rod won't go on the fixture, these often went missing or were never issued to the workshops, on everyday rebuilds, a quick test assembly w/s tool is a bar ground to size, once the rods are hung it's run through all the rod eyes, it won't pass through a bad rod, I still have a 22mm beetle tool, but I use the wrist pin for 24mm Wassers, not quite the same as a long bar, but it picks up twisted rods, if the pin passes through ok, you are good to go.