Rob, pretty sure that was a marine engine Race boat,as i remember! Jag V12s.
but take in mind marine engines use sea water to cool them thru a heat exchanger !
highly doubtful you can overheat the oceans!
and overheat was the bane of jag V12s, about 75% of V12 s went down because of heat conditions.
ron
Stock V12 rods are good for in excess of 7500rpm. Though much heavier than an equivalent 6.0 Chev rod, they are very strong.
remember, these engines were designed as a Race engine (Refer XJ13)
Norman if you grind the V12 crank down to 2” to suit Chevy rods how does that affect the strength of the crank?
when you grind a crank smaller you also take off the hardened surface !
would be more costly to either electric induction or cheaper to NITRIDE the bearing surface!
depending on the metal quality, costs could be expensive!
and decrease strenth, causing possible cracking !
but money no object a custom V12 crankshaft could be made!
You can’t reduce crank pin to Chev size of 2.00" as you will cut into the oil feed holes to the crank pin.
You can use 350 “FORD Windsor rods” as they are a nominal 2.300" size.
I do use Chev rods (with 302 Windsor bearings - 2.124") on my 7.5L engines, but use a different design of oil feed.
The 7.5L engine uses a TWR crank forging
LongJohn, have replied at forum.
Regards, Norman.
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Thanks for the that. I was assuming people were somehow grinding the crank down to 2”.
What sort of torque and hp do your 7.5l engines make?
Street engine is 550ft/lb and 400HP
Is that using standard cams, heads and intake and exhaust manifolds? Do you use HE heads and if yes with what compression ratio? Thanks.
I use Flat heads modified with a combustion chamber with larger (1.75in.) Intake valves with 11:1 CR. Intake and Exhaust ports ported and polished, std. cams.
You could use the HE heads with std. cams but you would only get about 320HP because as previously stated, you can’t get bigger Intake valves in the HE head without major welding and machining.
It was cheaper to modify the Flat Heads.
With “Competition” type cams in excess of 600HP would be available, but this not practical for “street use” in Australia as the highest speed limit in any State here is 130km/hr (80mph.) and exceeding that by more than 30km/hr. results in on the spot loss of Licence, confiscation of vehicle and hefty Fines.