RV8 Custom crank

[jfjfjf2]

I,d like to get a light weight crank made but I need a technical drawing as the people I am asking to quote have never made one before. Does anyone have access to one for the large journal Rover V8?

Thanks,

Julian

[roverman]

Julian, I suspect "John Eales" and others who make/sell stroker cranks, have drawings. They "may" not be free with them, since you aren't buying crank from them ? Billet crank ? Cast/forged 4340 ? Might be easier to supply them with a sample oem crank. Application ? The Ford Windsor raw forging can be machined to fit, and should handle ALL the hp/rpm you can throw at it.  Good Luck, roverman.

[jfjfjf2]

Art - I'm trying to source an 83 mm stroke lightweight billet crank and combine it with a 97 dia bore block. I thought I'd get quotes from Scat and Crower and see where that gets me. The car is a '94 TVR Griffith which weighs under 1100 kg.

You might be right about having to send oem cranks, I am trying to avoid the time and expense involved in sending two cranks (which I don't have lying around) to the US. I'm sure crank suppliers here in the UK would be very helpful if I was buying from them but those I have seen though man enough for the job are somewhat agricultural. I might know someone with a drawing but they are very hard to pin down, hence the post.

Thanks for your reply.

Julian

[roverman]

I am within driving distance of both. Eagle made a crank for a "V8Buick" forum member, off the radar, turned into a BIG OL" MESS !  You aren't going to like the billet prices. Perhaps Scat could be tempted to machine raw ,sbf 4340 forgings into sbb/rover cranks, say (3) ? They have the raw forgings.  With TA heads available, a "few" of the Buick folks would be on board. Jim B., do you agree? According to Triumph Rover Spares,"the Rover will produce 600 hp.", with ported TA heads,all motor. This makes the available cast cranks pretty marginal.  Cheers, roverman.

[minorv8]

Julian, have you considered Farndon ?

[jfjfjf2]

Jukka - Farndon could supply the correct spec but they don't make anything like the Scat superlight, I know I would get a good crank fit for purpose and I may well end up buying from them but I'd like to explore other possibilities.

Regarding prices Art, this is a very small country and everything is expensive, a Farndon crank would cost c.£2500 or near enough $4000. It's rumoured that TRS are sourcing cranks for the TA heads in the Far East but I doubt they will be any cheaper to the end user than a custom crank from the US. If I had any sense I'd use an LS crate engine but that wouldn't warm the cockles of my heart.

Julian

[rrrover 5L]

I may know something here.....

I'm fairly certain that Ford v8 forging blanks are where most Rover/Buick customs emanate from.

Mickey Thompson used them in his Buick powered desert racing buggies.

I have a Bryant Ford billet sitting in a Rover block which needs some widening on the journals, a custom rear seal & flywheel and some nose work to complete. I suspect someone like Moldex who regularly produce Rover/Buick cranks would modify them with ease.

Byron's twin turbo project B has a custom Moldex billet crank in it.

John

[BlownMGB-V8]

I think one or two of the SBB drag racers are running Moldex cranks. Very likely what you are talking about. I also recently read a post where someone was lightening a crank by chucking it in a lathe and turning down the counterweights. You'd have to get it balanced of course but with light rods and pistons that shouldn't be much of a problem.

Jim

[roverman]

Julian, I can appreciate your not abandoning the Rover V8. 97mm bore? Is this a Wildcat symeese block ? If not, it's likely the sleeves will be wet ? I think the rover V8 is about to have a long moment in the sunshine. With the right material a crank benefits from pendulum cutting the counterweights and hollow boring the crankpins. This removes weight with best benefits. Turning down the counterweights diameter is best for final balancing. I'm not convinced oem Buick cranks will sustain 700-1,000 hp. with any reliability,(but that IS the rumor). Onward, roverman.

[jfjfjf2]

Jim - Thanks for the suggestion, I've emailed them. Art - Coscast block bored as for 96 mm but with thinner flanged liners gets you 97 mm. I forget what they are called, I'll post at a later date with the spec. Re the crank, I'm not seeking 700+ bhp but I would like to have 7500+ rpm on tap and a highly responsive engine. Even if the oem cranks could cope with torque/bhp/rpm demands I want to lower reciprocating mass. I will be using the TA heads and I'd be surprised if anyone else intending to wouldn't be up rating the bottom end. The first crank manufacturer to cater for our needs should pick up business from most US/UK TARV8 head buyers.

Julian

[roverman]

Clan, I have emailed "Bryant Racing Cranks" and Scat. Higher production #'s should favor forged cranks, cost wise.Update, looks like I will be sending a "sample" crank to Scat. A light dampener and flywheel/clutch assembly, will also rev up/down faster. We shall see. roverman.

[jfjfjf2]

Art - Nice one.

JF

[roverman]

Let's start a want list. I think 2.5" main size and 2.1" rod journals are good for sbc rod selection, remember hollow crank pins ? Rover 1 pc. rear seal and standard rover bolt pattern. Early or late snout ? I suspect  snout could be later/longer and re-machined, if needed. Grooved mains not needed. Cross drilled-maybe.  Let's go ! roverman.

[rrrover 5L]

I'll see if I can take a couple of shots of the Bryant crank in & out of the block. It has turned down counterweights and some big plugs of Mallory Metal to achieve balance. Nice hollow crank pins, too.

Going to be 104 degrees in Melbourne tomorrow. I wont be spending too much time in the shed:-)

[minorv8]

Would a 2" rod journal size be better for stroker clearance. I have a 91 mm stroke (3,58") and 2" SBC Crower Sportsman rods just clears the 4,6 block. Later Chevy rods with 2,1" will not fit without grinding.

John, I am a bit envious since we have 3 ft of snow and 30 degrees in Helsinki. Enjoy !

[rrrover 5L]

You're right, Jukka. I shouldn't complain too much based on your weather. I'm looking forward to the F1 GP here in a few weeks & the return of Kimi the flying Finn.

I have a set of 6" Carrillo's with Honda journals. I'm thinking of offset grinding & making the crank 3.7 stroke. With the 3.7 bore, I'd end up around 5.2 litres....

[jfjfjf2]

Art - I'd go with the 2.5" mains but would prefer 2" big ends, that's not an area in which I'd like to add weight, crank pin to take Chevy rod, still plenty of off the shelf rod choice. I need the long nose. Scat frown on cross drilling, I'll let them talk you through their thinking on this, they have an explanation on their website.

Re the 87 mm bore, using thin wall inducted iron liners. I'm told the Dodge Viper uses them.

I'm ready to buy as soon as they're ready to make them.

Julian

P.s. I'm told I'll have drawings tonight, but the TVR specialists I deal with have just ceased trading so everyone has a lot on their plates. They will be useful to get other quotes.

[minorv8]

Julian, you wouldn´t happen to have a spare TVR 500 crank ?

John, it´s interesting to see how Kimi will succeed !

[roverman]

3.7" stroke, 6" rod, 8.96" deck(un-cut) leaves 1.11" for ring package. 1.85" rod journal and 7,500 rpm, road racing ? Dry sump ? I forgot, the rover block is "narrower" at the pan rails than 300-350 sbb.Cheers, roverman.

[jfjfjf2]

Jukka - I'm going to mothball my existing engine. I'll ask around.

Julian

[rrrover 5L]

with that bore & stroke I'd end up with Engine Displacement (CC) 5215.4 using the standard liners..I'm thinking of cutting grooves & inserting copper O rings between top of sleeve & block to overcome potential leakage behind sleeve...Does anyone have thoughts on this idea? I have used flanged sleeves in the past, but $$$$$

Art- Road racing & dry sump for sure..Quite a few people here using TA head's too....Not sure on the bodyshell yet...have a partially done TR7, but am beginning to lean more towards MGBGT...MG racing is a very healthy category in Oz...Some TR's, TVR's & others race by invitation in the class, too.

Jukka- Kimi could get Lotus back in a winning position:-)

John

[roverman]

John and clan, I bought "Tsubaki-made in Spain", flanged liners through Wildcat, "Ian". As I understand it, made in Spain, sold to OZ, then Ian and retailed to me. Fortunately, they weren't wore-out in the process/lol. With all the $'s/labor of installing sleeves, I would only use "flanged". If you left approx .002" proud of deck, you'll have suitable o-ring effect, without the hassle.  Who is "Byron" and his twin turbo MGB ? Are they "really" making 600 hp as TRS claims, all motor ? Cheers, roverman.

[jfjfjf2]

Email from Moldex, they can supply RV8 crank, they have the spec. Time frame c.12 weeks. I last spoke to TA P a couple of weeks ago, they said that their CNC machine was repaired, the new operator had settled in and he was working his way through a couple of rows of 455 heads. Next up would be the Rover heads. I would rather not be in the position where the crank was the last thing I was waiting for. I would ideally like to run the new engine in on the old stage 3 heads and get some torque/bhp figures for comparison. I'll be interested to hear how long Scat would take.

Julian

[Wotland]

Whoo very interesting post. I just opened similar post on uk forum to find a compagny to machine my crank.

I have one bare casting crank sourced to LR factory :



Maximun stroke with this crank : 91.5mm

I am looking also for a 94mm stroke crank. There is a small compagny who can cast full counterweight crank for RV8. Cranks can be machined to 94mm stroke without problem.



P.S. Jukka if ever I have one of MCD TVR 500 crank prototype.

[rrrover 5L]

Art, do you mean Ian @ TRS supplied the sleeves? I dont know about 600hp, but a friend who races a fairly fairly quick MGBGTV8 was following one of these engines in a private practice session at Phillip Island a week ago. He said it pulled away from him at a huge rate of knots.

Theres a story elsewhere on this website about Byron Listers Turbo project "Biteme". The pictures below show the Moldex crank & a "Halo" bottom end that John Davis in Sydney used to sell, It make 630 hp with 21psi of boost.

I've got a dyno clip somewhere

John