Replacement head made legal ?

[roverman]

Perhaps now might be a good time to start lobbying various sanctioning bodies, to allow a "replacement head", for the Rover V8 ? Obviously not stock classes, but further-up ? I'm not sure if "something" like the Merlin head, might be considered. It has standard valve centerlines @ 1.660" ,and inline valves. Just a thought, Cheers, roverman.

[Preform Resources]

Art is this a head from World products,,,or from England ? any links?

Dave Craddock

[Phillip G]

Road race fans,

I hope to get a ruling on "legal" cylinder heads from SCCA for the 3.5 Rover V8.

Recent ruling has come down that any manifold may be used - and I bet there are good, better and best manifolds.

However induction is pretty much restricted to the Holly 390 with a specified restrictor plate.

Any thoughts on the best manifold ( with the "legal" cylinder heads) or better manifold (than the Eldebrock) for the 3.5 Rover V8 with the above induction restriction ?

keep them on the track,

phillip g

[Moderator]

If you look carefully at the various MGB GT V8's that are currently being vintage raced in North America, you'll notice that they're pretty much all running different cylinder heads. Arguably, the quickest of these cars/drivers is Jerry Richards, and he's running reworked stock Buick 215 heads on a Buick 215 block. I'm not aware that SVRA restricts heads on "Rover" mills at all - and personally I can't comprehend why they would even want to restrict cylinder head choice. SCCA should be no different. All the available heads are aluminum. They all have two valves per cylinder. They're all going to get custom port work. If overhead cams or four-valves per cylinder start showing up on Rover mills, then the rules will need reconsideration. Until then...

[roverman]

Dave, World Products has a Rover head ?? One got by me, hmm. I bespoke of the Merlin head, as a "possible" replacement.Side note, "Steel" hasn't ported their head, as it was designed for street use,(their words). Phillip,Regarding  manifold design,I "think" this means sheet metal is ok ? Before you pick a suitable design, for that flow challeged carb, I would map what gear ratios for "all" the tracks to be run, and useable rpm. range required of the motor. If you can run the rpm., perhaps a short tunnel ram or vintage Nascar style, cross-ram, in sheet metal ? I suspect the huge plenum area of these designs, and the benefit of ram tuning, should help that little carb. Good Luck, roverman.

[Preform Resources]

Art,  I was asking you about the world products as they have a merlin product line,, what merlin head are you referring to,
just curious.
Dave

[roverman]

Sorry Dave, Too many Merlins. World Products calls their BBC heads Merlin and Real Steel calls their Rover head "Merlin F85". F85 was Olsmobile's tribute to the "Jet Age", Jet Fire etc. Why on a Rover head?, got me, maybe the (6) bolts per bore, your not supposed to drill ?  The TA head uses (5), therefore I think, "Cinco muy pricey", to be a suitable name.roverman.

[Phillip G]

MG Rover racing gang,

Now there is some discussion on how ro make the Rover 3.5 engine - within the SCCA GT 2 rules - competitive !

Next round of a Rover 3.5 engine build - after entering, showing up and  finishing 4 SCCA National races in Division and qualifying for the Runoffs in 2011 in GT 2, will include input on the V8 Forum on how to achieve increases on horsepower and reliability on the SCCA required SCCA "LEGAL" 3.5 Rover engine, in order to arrive at Elkhart in September 2011 and be on the starting grid  for the qualifying laps.

More input and suggestions on the 3.5 Rover engine will go a long way on the next engine build.  Honestly.

keep them on the track,

phillip g

[roverman]

Phillip, To make educated suggestions, we need lots of data.Usable rpm. required,(closely tied to gearing) ? Max bore/min. stroke? Sheet metal intake ? Replacement head with standard valve centerlines ? Mechanical roller ? Varicam ? Drysump ?All of Dan Jones questions on head flow, valve/port sizes etc. Budget ? We're just getting started. I'm sure you know, winning is a lot more that just luck. Cheers, roverman.

[Phillip G]

Art,

Thank you for your input on the 3.5 Rover V8 mods.

After the rear axle swap - which comes before the next V8 engine - I will have available rear axle/final drive numbers as well as transmission gear ratios readily available on the GT2 RV8.  We hope to swap out the rear axle over the xmas holidays.  This move forces new wheels (of the correct offset).

Anybody need a good early model MGB rear axle (with 3.90 & 4.30 locked differentials)  with Wilwood disc brakes and a set of 4 each 15X7 11lb SpinWerks alloy wheels - all set to go ?

Art, after the real axle change out, I' ll share all the info I can on the next engine build for more performance.

keep them on the track,

phillip g

[Moderator]

Phillip, when you're really ready to sell the wheels and the axle, please post them (in two separate ads) in our classified section. I want the wheels, but I don't think I can make them fit without a whole bunch of bodywork. By the way... how much offset do they have?  I've met a lot of people who might be interested in the axle, and I'll be happy to send some e-mails when I can link to details.

[Phillip G]

MG V8 racing enthusiasts,

How do you feel and what do you think about a shortened 8 inch Ford ,5 lug, rear axle with a Ford Positrac final drive ratio of 2.80 for the GT RV8 ?

Bearing in mind that a 5 speed, Pontiac Firebird T5 is to be coupled with the 2.80 final drive  Ford 3rd member ?

Will it take excessive rpm to accommodate the 2.80 final drive ?

be nice to get it right, first time out of the box.

keep them on the track,

phillip g

[Moderator]

2.8:1 sounds like a mistake to me. Just for reference, Les Gonda selects between 3.9:1 and 4.1:1 gear sets from weekend to weekend depending on which track he's running, and Keith Burnett set-up his MGB GT V8 racecar with just a 4.1:1 gear.  On the other hand, both of those guys are using a 0.8:1 fifth gear whereas your Pontiac-spec box will have either a 0.63:1 or a 0.73:1 overdrive unless you rebuild it otherwise. You might find it helpful to play with a gear calculator like the one Dan Masters created for our website so many moons ago - here's a link to that: <a href="http://www.britishv8.org/Articles/chart.xls">http://www.britishv8.org/Articles/chart.xls</a> (Your engine builder should be able to help you determine optimum shift points, based largely on camshaft specs.)

[roverman]

Phillip and clan, Did you "look" at the new midget QC. for $1K/offer ? In leiu of QC. rear, a "modular"od.,(5th), would be a plus.2.80 final drive, .63 and .73 overdrive ratios will be useless for road racing.To put this in perspective, a 2.80 rear end ratio, coupled with a .73 5th will provide less than HALF of the torque available than that 4.1 ratio w.o. overdrive ! You must know the hp/torque curve of the motor to be raced,(should max hp at 7k ++ rpm),tire dias and decide the top speed,(end of straightaway/very near "red line"), at the fastest track, you intend to race. Then, and only then, are you ready to pick suitable ratios. Your engine will never "pull" the overly tall ratios, your discussing.Good Luck, roverman.

[Phillip G]

Curtis,

Art,

Thanks for the good advice on the final drive/ratio unit on a Ford 8 inch rear axle.

Never having a 5th/overdrive gear on my 3 syncro MGB GT, 4 speed gearbox, I have a lot to learn about setting up a T5 with a low rpm V8.

good advice is everything and appreciated.

keep them on the track,

phillip g

[roverman]

If SCCA allows the "replacement" head, next should be perhaps (2) , 2bbl carbs,Holley or Webber ? They could follow the same sizing and restrictor size. This will permit equal runner lengths and unified air/fuel ratios, between cylinders. I don't believe anyone, is seriously concerned the the MG RV8 , will over-power the 350Z ? 2cents, roverman.

[castlesid]

Philip,

Why are the US regs so restrictive, the RV8 should have a 3.9 engine anyway and the UK there are classes in BCV8 championship for 3.5 and 3.9 full race engines with up to one choke per cylinder but no EFI so 350 BHP is possible with Rover castings.

Other race series may be even more liberal.

Kevin.