MGB-GT REAL MGBGTV8: How much???`

[BritishV8]

RickB asked: "And what is the comparison re: torque?"

Here are numbers from Motor (weekly) magazine published tests:

1970 MGB GT: 95bhp at 5400rpm, 110lb.ft. at 3000rpm, 0-60mph in 11.6s
1967 MGC: 145bhp at 5520rpm, 170lb.ft. at 3500rpm, 0-60mph in 10.0s
1973 MGB V8: 137bhp at 5000rpm, 193lb.ft. at 2,900, 0-60mph in 7.7s

(The MGC that Motor tested was a roadster and it was tested with a hardtop.)

The V8 also got better fuel economy than the MGC, and it was rated for use with cheaper, lower-octane gasoline than either the MGC or the B-series four.

 

[vagt6]

British V8, thanks the link to your website, an excellent documentation job on your build. It's very innovative and a lot of hard work, too. Your pictoral essay provides some interesting and useful innovations.

I'm a bit "traditional" with restoration and improvements on these cars and try to keep my mods somewhat period-correct, or at least reversible to the original parts/configuration. But, that doesn't mean that some of the American "hot rod" ideas of others can't be usefully integrated into period-correct build concepts for LBCs.

Thanks for posting, and thanks for your input on what is possibly the most exciting MG of all, the MGV8. /bcforum/images/%%GRAEMLIN_URL%%/driving.gif

 

[RickB]

Thanks BritishV8 - I thought maybe Torque was the star of the show with the MGB V8.

I can see how a little bit of minor modification like the higher compression pistons would really make one of these cars shine.

I've driven a C extensively and though the HP is really nice I always felt like they could use a bit more in the Torque department. Sounds like the V8 would be a great car to drive!

 

[WA1KWA]

"Horsepower sells cars - Torque wins races." - Carroll Shelby

Colin

 

[vagt6]

Regarding the Laycock "LH-type" overdrive

Okay, it was about to kill me to discover more about the Laycock LH type overdrive that was installed in the above MGV8. So, I looked no farther than to John Esposito on his Quantumechanics website for the answer, and here it is along with the link:https://www.quantumechanics.com/categories.php?op=newindex&catid=12

The Laycock LH overdrive was used in the MGB from 1968 to 1980 as an optional extra. Only 2 out of every 100 cars imported to the USA had this option. (Interestingly enough, all cars in the UK came with overdrive! – is that backward or what!)

Today, most restorations are being completed with overdrive transmissions even if the original car did not have one fitted. This is an almost mandatory option if any amount of highway driving is done as it reduces noise, engine wear and increase fuel mileage (not counting increasing the value of the car itself).

What I would like to show this month is a problem we see in almost every LH overdrive we inspect today. The two examples shown demonstrate what we are calling “aged out” (as opposed to worn out). The clutch material has deteriorated over time, but due to age, not wear. Even transmissions with less than 40,000 original miles show these patterns of deterioration on the clutch material. Let’s face it gang, the original clutches were not designed to last 30 years! You can see from one photo an extreme example where all the clutch material has completely fallen off the clutch sliding member.

The other photo shows another clutch with some material remaining, but obviously not for much longer. Sometimes we find the entire clutch material intact, but separated from the sliding member, just “floating” in the overdrive. Symptoms of this deterioration are slipping or “free wheeling” in overdrive. The slipping or “free wheeling” can also occur in non-overdrive. We find that the overdrive lining is usually the one most deteriorated. We surmise that this is due to low oil pressure in the overdrive circuit which causes the clutch to slip, stressing the material. This results in a more rapid deterioration than the non-overdrive side, which is spring driven and has a more positive engagement. It may also be due to the type of oil as transmissions with 90 weight oil in them have more advanced evidence of deterioration than those with 30 weight non detergent oil.

Based on our experience we always replace the clutch on every LH overdrive we rebuild. One customer took a chance with a used overdrive that initially worked fine. A few months later, the clutch material fell off in Albany NY, 300 miles from his home. He was lucky to make it home without damaging any other parts of the transmission. Once the clutch material disintegrates, it is turned to a mushy paste within the overdrive due to rapidly moving parts. (Sort of like a MG Cuisinart) Since the transmission and overdrive share the same oil, the paste eventually finds its way throughout the entire transmission and overdrive. This tends to jam synchros and bearings, plug up oil passages, and generally cause all sorts of havoc in the transmission and overdrive, to the point of possible major failure.

We hope this discussion will help MG owners understand why we say there is no such thing as a good used LH overdrive anymore! BTW, the new relined clutches made today supposedly have better material than the original, although only time will tell as to how long they will last!

 

[BritishV8]

Re: Regarding the Laycock "LH-type" overdrive

We've finally got Kevin's MGB GT V8 gallery page pasted together and uploaded.

Check it out here! https://www.britishv8.org/MG/KevinRichards.htm (57 photos!)

I'd be very grateful for additional photos of other "factory original" MGB GT V8s... If you have photos to share, or if you're willing to take some, please get in touch!

 

[billspohn]

Yes, if memory serves the engine used was a low compression Range Rover unit.

Colin

Yup - 135 BHP (less than the MGC) when they could have gone for the 185 BHP SD1 engine - idiots!

Of course they did the same thing in the TR-8, which makes them pretty lukewarm in performance as well.