RE: MGB GT V8: You Know You Want To
Discussion
RoverP6B said:
jason61c said:
If it had a decent v8 fitted instead of a crappy rover one maybe.
Oh yes, that awful crappy Rover V8 engine, only one of the longest-lived and biggest-produced engines in the history of car production... my P6 with the same engine was mechanically bombproof (well, apart from the time I broke a layshaft on reverse gear... but this MGBGT has the stronger 5-speed LT77 box) and made a lovely noise.You have to spend serious money to get decent power from these engines. The only benefit over other V8s is a weight saving - useful in certain applications (like mine) where a SBF or Chevy lump would be too heavy.
v8250 said:
You don't want too stiff a body chassis. If too stiff the body will tear at its weakest point/s. Having a Heritage shell will make no difference unless they stitch weld the seams, which is an option from BMH. More importantly is to ensure the shell you are starting with is in perfect shape, this means solid metal and no rust. Add any additional structural support req'd and then you know the power is not going to do damage. Again, too stiff a shell on a road car and you'll be in trouble. As a test, if any of you have a car with circa' 200bhp...drive along for a few miles and stick your fingers between the upper door/window frame and the roof. You'll be amazed at how much movement there is. If this natural movement is removed it will be transferred to the next weakest point...and you don't want that to be a metal seam.
One rather wonders why manufacturers go to such lengths to achieve great stiffness - 33,000Nm per degree in the case of the Jaguar F-type Coupé. That said, I have done as you describe with my 170bhp E39 520i Touring (haven't yet done it with the 242bhp 535i) and yes, I have noticed a certain amount of flex.Escort3500 said:
They're not that great an engine IMO. I've got one in my Mk 2 Escort with an LT77 'box. Sure, it sounds nice and has reasonable mid-range torque, but it only produces about 170hp with SD1 heads, a Real Steel cam and an Edelbrock intake manifold and carb.
You have to spend serious money to get decent power from these engines. The only benefit over other V8s is a weight saving - useful in certain applications (like mine) where a SBF or Chevy lump would be too heavy.
Considering a bog standard 3.5 from the late 60s makes 184bhp, the SD1 EFi makes 190bhp (210 in the Twin Plenum), I'd like to know how, after all you've done, you're only making 170hp. Are you sure that isn't wheel horsepower and that you're not actually making about 210 at the crank? I'm aware that the Rover engine isn't the best or cheapest for serious power, but it did exactly what was asked of it for thirty-six years of production and did it very well. Without that engine, may I remind you, we wouldn't have had the Peter Wheeler-era TVRs, TVR itself would have gone bust and, ergo, the TVR lunatics wouldn't have started up Pistonheads, and we wouldn't be here having this argument! You have to spend serious money to get decent power from these engines. The only benefit over other V8s is a weight saving - useful in certain applications (like mine) where a SBF or Chevy lump would be too heavy.
Incidentally, the Rover is no longer the engine to use if you're after a compact, lightweight unit. General Motors' LS series, ranging from the 5.7 LS1/LS6, 6.0 LS2, 6.2 LS3 (with LSA and LS9 supercharged variants) to the mad 7.0 LS7 is actually slightly smaller in physical dimensions and weighs about 200kg (the Rover is 220kg). So, if you want lightness and power, get onto GM and order an LS crate motor...
RoverP6B said:
Escort3500 said:
They're not that great an engine IMO. I've got one in my Mk 2 Escort with an LT77 'box. Sure, it sounds nice and has reasonable mid-range torque, but it only produces about 170hp with SD1 heads, a Real Steel cam and an Edelbrock intake manifold and carb.
You have to spend serious money to get decent power from these engines. The only benefit over other V8s is a weight saving - useful in certain applications (like mine) where a SBF or Chevy lump would be too heavy.
Considering a bog standard 3.5 from the late 60s makes 184bhp, the SD1 EFi makes 190bhp (210 in the Twin Plenum), I'd like to know how, after all you've done, you're only making 170hp. Are you sure that isn't wheel horsepower and that you're not actually making about 210 at the crank? I'm aware that the Rover engine isn't the best or cheapest for serious power, but it did exactly what was asked of it for thirty-six years of production and did it very well. Without that engine, may I remind you, we wouldn't have had the Peter Wheeler-era TVRs, TVR itself would have gone bust and, ergo, the TVR lunatics wouldn't have started up Pistonheads, and we wouldn't be here having this argument! You have to spend serious money to get decent power from these engines. The only benefit over other V8s is a weight saving - useful in certain applications (like mine) where a SBF or Chevy lump would be too heavy.
Incidentally, the Rover is no longer the engine to use if you're after a compact, lightweight unit. General Motors' LS series, ranging from the 5.7 LS1/LS6, 6.0 LS2, 6.2 LS3 (with LSA and LS9 supercharged variants) to the mad 7.0 LS7 is actually slightly smaller in physical dimensions and weighs about 200kg (the Rover is 220kg). So, if you want lightness and power, get onto GM and order an LS crate motor...
On the subject of leaf springs - I had composite rear leafs made up for my Datsun Roadster, following quite a few others who had done the same.
Replacing the steel leaf pack with composite may be the single best mod I have done to the car. It eliminates over 20 kilos of weight from the rear end, half of it unsprung. The rear axle responds better, carries weight better, and makes the car a joy to drive.
If you are okay departing from original equipment, I highly recommend talking to a composite leaf fabricator. The nice thing is that it is easily swapped back if your car becomes worth enough for originality to matter. Unless your car is concourse-worthy, I doubt any future owner will ever want to revert to steel leafs.
Replacing the steel leaf pack with composite may be the single best mod I have done to the car. It eliminates over 20 kilos of weight from the rear end, half of it unsprung. The rear axle responds better, carries weight better, and makes the car a joy to drive.
If you are okay departing from original equipment, I highly recommend talking to a composite leaf fabricator. The nice thing is that it is easily swapped back if your car becomes worth enough for originality to matter. Unless your car is concourse-worthy, I doubt any future owner will ever want to revert to steel leafs.
Escort3500 said:
Sorry, I didn't make it clear, the 170hp was at the wheels so probably about 200 at the flywheel. They're not the worst engine out there and I acknowledge that they've found homes a number of decent cars, but they're showing their age now and, as you say, the engine of choice these days is the LS series. There are a couple of LS1-powered Mk2s on the forum that have got me thinking I have to say
Thought as much - and transmission losses will be variable. While, in the context of entire cars, I wish that torque and power figures at the wheel were more commonly quoted, in the context of engines alone, the power at the crank is more useful to know. Does Ford make tuneable V8s in the Rover/LS way, or are the Modulars strictly factory-only? The BMW M62 and I think sometimes people forget what an old engine the Rover V8 is - introduced in 1967 and not an entirely new design even then (Buick and Oldsmobile had it from 1961). People don't moan about what a heavy and sluggish engine the 1956-introduced BMC C-series straight six is (and it IS heavy and sluggish - makes sod all power and weighs nearly the same as a Jag V12!), they just take it as what it is - an old engine found in classic cars. It strikes me that the Rover engine's greatest strength is also its greatest weakness - that it was such a good engine that it remained in production for 41 years from its original introduction. The C-series lasted only 15 years - OK, politics and the BL merger played its part in that, but suppose the C-series, somewhat updated with EFi and increased displacement in 3257cc and 3757cc variants (worked out from the % increases in displacement the Rover V8 got), had still been available in a large Austin barge or medium size 4x4 [think Austin Champ, updated as a Suzuki Vitara competitor] until 1997?
To make a more valid comparison, the even more long-lived Jaguar XK6 inline six lasted in production for 44 years, 1948-1992 (beginning in the XK120 roadster, winning Le Mans [and just about everything else in sight in that era!] in the C-type and D-type, powering every Jaguar sports car from the XK120 to the Series 2 E-type, all of Jaguar's saloons from 1950 to 1986 and ending its days in the Daimler DS420 limousine and hearse - so an even more versatile engine than the Rover!) and, like the Rover, remains in small-scale production by independent specialists (RPI and others do Rovers, Crosthwaite & Gardiner do XK6s, including for Jaguar's own new lightweight E-type). Yet nobody complains about that being in any way a poor engine, nor did they ever. They just banged on incessantly about what a stunning engine it was and how it had become a huge, indelible piece of automotive history - and absolutely rightly so, because that's exactly what it was.
The Rover may only have lasted 41 years to the Jag's 44, and didn't enjoy such prominent headline-grabbing racing success, nor did it have the romantic back-story of having been designed during nights on a rooftop on paper illuminated by the fires of Coventry burning as the bombs fell, but, if the XK6 is the greatest engine produced in post-war Britain (it'd be damn near the top of the greatest of any time, any country!), the Rover V8 is certainly the second, with the Jaguar V12 a close third (OK, only produced for XJs and XJSs, but between them and the XJR series of racing prototypes, plus what Lister did, it's certainly one of the most notable), and the Rolls-Royce/Bentley L-series V8 must get a mention (1959-present, 55 years and counting, but only put in one line of models and never raced nor used in third-party sports cars AFAIK) plus an honourable mention for the BMC A-series for powering everything from the Austin A30, Morris Minor and Spridget to the Mini (and, in diesel form, a great number of tractors and boats) for 49 years, 1951-2000 (58 years to 2009 if you include the Datsun/Nissan derivatives, which survived in light commercials in developing countries until just five years ago), which wasn't a special engine as such and certainly doesn't make much power, but enjoyed great motorsport success and gave generations of Britons (and others) cheap, accessible motoring (and often their first driving experience). I'm not sure I approve of the last - without the A-series, I dare say our roads would be much quieter, much emptier of idiots, and the Beeching cuts wouldn't have happened... but I digress... the B-series also deserves a mention as it too was quite long-lived, 1954-1980, 26 years, and that too went in a wide variety of saloons, hatches, sports cars (including the MGA, then the MGB, before the V8, not to mention the early TVRs - another engine without which we probably wouldn't be on this forum!), Leyland Sherpa vans, a variety of German commercials (including Mercedes-Benzes) and Massey-Harris combine harvesters, plus a whole bunch of tractors and boats. It's a very heavy engine, more so than any Rover V8, and makes little power, but people seem to take it on its own merits rather than talking it down, perhaps because it didn't last so long.
Continuing with my current train of thought as to the great engines of our time, I wonder how long Jaguar's AJ-V8 family will last, and whether that will take its place at the legendary engines table - I know that it is used in motorsport, in the XKR-GT2/3, but that does not seem to have enjoyed significant success and hasn't enjoyed the advantage of a factory-backed works team. It certainly hasn't won (and probably won't ever win) Le Mans outright like its illustrious indirect predecessor. BMW's M60 V8 and derivatives thereof (M62/N62) should probably be included, given its longevity and popularity in non-BMW cars (including Ascari, Morgan and Wiessmann). The Toyota UZ engine found in the LS/GS/SC 400/430 and their Toyota rebadges, likewise - reasonably long-lived and used in a lot of things (seems to be going in a lot of MX5s these days). Toyota's JZ series straight sixes (and their RB counterpart at Nissan) also seem to have been among the more significant engines of recent times, and arguably should have lasted longer rather than being replaced by V6s.
I don't think BMW has produced a complete clean-sheet design straight-six since 1977, but they've used so many engine codes to denote some significant differences between generations that I don't think it counts as one engine (the current 3-litre turbo N55 is based on the N54 twin-turbo, its naturally-aspirated N53 stablemate is based on the N52, which [like the N54] is based on the M54, which was an Alusil+VANOS+displacement reworking of the M52, which was a Nikasil recasting of the hitherto iron-block M50, which was a twin-cam 24-valve re-head of the SOHC 12-valve M20, which dates back to 1977). Same could be said of the V12s (including the S70 in the McLaren F1) - they're all based on the M70, which itself is two M20s on a common crank-case, but too many changes each generation for it to be just one engine...
articulatedj said:
I had composite rear leafs made up for my Datsun Roadster... Unless your car is concourse-worthy, I doubt any future owner will ever want to revert to steel leafs.
If you're not going to exhibit it thus, wouldn't it make more sense to do an IRS conversion, such as is available for MGBs? I also don't know whether concours (note, no 'E' on the end - a concourse is what is located between the buffer-stops and the street at railway termini, for example - sorry to go all spelling Nazi!) would punish you for composite leafs, would they? It's not a structural alteration as such and is reversible in minutes. I remember that inserting an extra leaf to the transverse rear leaf spring on Triumph Heralds, Spitfires and GT6s was a popular modification to stiffen them up a bit.Slightly O/T, does anyone recall if the Triumph 2000/2500/2.5PI had a transverse leaf or coils?
I had a factory V8 for many years and loved every minute. Had it rebuilt and got rid of the nasty rubber bumpers and converted it to the lovely old chrome grill style. Much nicer but probably upset the purists. The exhaust note used to regularly set off car alarms, which was fun....for me. Handling even after lowering was, let's say, like a pendulum in the wet and quite good in the dry. The danger made it fun though! I still miss it but £22k is an awful lot for one of these whatever's been done in my opinion.
Church of Noise said:
Most interesting reading, thanks!
Are there any must-read books on the subject on engines & their histories and development?
I'm afraid I wouldn't know, all the above is from memory, absorbed over the years. Wikipedia's references sections on each engine's article might be a good place to start, also have a look on any specialist websites you can find.Are there any must-read books on the subject on engines & their histories and development?
Church of Noise said:
Most interesting reading, thanks! Are there any must-read books on the subject on engines & their histories and development?
Hi Alex, for the Rover V8 there are two very good books...http://www.amazon.co.uk/The-Rover-Engine-David-Har...
http://www.amazon.co.uk/Power-Rover-Engines-Track-...
For the Jaguar XK/XJ engine these are great...
http://www.amazon.co.uk/Jaguar-XK-Engine-History-R...
http://www.amazon.co.uk/Power-Tune-Jaguar-Engines-...
I have these on the bookshelves...they're great reading and even better for technical reference.
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