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[BazaJT]

Been reading about a chap who's restored a Trans Am building an exact replica of KITT-even got David Hasselhoff to sign it!Obviously it's not the super fast car  that was on telly.It runs the standard engine which the article says was 5013cc V8 giving 150bhp and the owner struggles to get 12mpg from it.150bhp from 5 litres is not an awful lot,is it because the yanks strangled it down for emissions or something?

[TheBoy]

Yank tanks in the 80s struggled to get euro levels of output from their massive engines.  Sub 200bhp from 5l was normal, where as the Euros and Japs were starting to approach the 100bhp/l mark.

[05omegav6]

The stupid thing is, running more power would actually have made it more efficient

[zirk]

The Rover 3.5 V8 lump was around 150bhp.

[BazaJT]

I seem to recall some years ago that a company that imported Corvettes used to make it one of their first jobs to strip off at least some of the emissions gubbins the yanks had to fit to get the engines to release more ponies,wondered if this was the same kind of deal,because only 150 horses from 5L is plain wrong!

[Nick W]

The Rover 3.5 V8 lump was around 150bhp.

Range Rovers, Land Rovers and MGBs were more like 125bhp. Injected engines were upwards of 190bhp. If you believe the quoted figures!  Most used Rovers make less due to wornout camshafts.


Most US 5.0l engines were down to about 120bhp by the mid eighties(mainly due to tiny carbs, weak compression ratios  and a bunch of seriously restrictive emissions kit), but they still make well over 200lb-ft torque at very low revs. All of them are utterly unbreakable in such trim. Low rpm torque and durability were always the American V8's prime attributes, and little has changed with the modern ones.

[Keith ABS]

  Very low octane rating of American fuel doesnt help much either

Keith ABS

[zirk]

  Very low octane rating of American fuel doesnt help much either

Keith ABS

That Moonshine stuff they make is pretty good, hic.

[TheBoy]

The Rover 3.5 V8 lump was around 150bhp.

Book was 155bhp from early 80s onwards, rising to 190bhp for the twin plenum, injected Vitesse and later Vandan Plas variants.

[minifreek]

Wasn't the Rover V8 a cast off from Buick.....?

Probably made too much power LOL

[zirk]

Wasn't the Rover V8 a cast off from Buick.....?

Probably made too much power LOL

Was originally a Boat engine before GM got there hands on it.

[Nick W]

Wasn't the Rover V8 a cast off from Buick.....?

Probably made too much power LOL

It was originally designed for, and used by Buick(and possibly Pontiac as well) They figured out a better way of producing light weight cast-iron V8s and so the extra expense and hassle of aluminium became less cost effective.
The engine's light weight made it popular for boat engines, and that was what caught the attention of Rover's engineers when they needed a replacement for an old six cylinder engine.

[jonnyboyws6]

If it's the same article I've just read, there's also a picture of the car in a cloud of tyre smoke, which would suggest the 150hp rating doesn't tell the whole story...

Horsepower is a mathematical equation for a rate of doing work (torque x rpm)/5252 The engine in the Pontiac (assuming it's original) will be a 305 Chevy, probably in LG4 spec, and the 150hp will be at about 4000rpm redline. The lack of revs make it look worse than it really is when we are used to comparing figures for European or Japanese engines that rev to 6500-7000rpm. Old American V8s have much more emphasis on bottom end torque to get a big heavy old barge up to speed quickly then plod along for hours and hours at cruising speed with the engine barely above idle speed, and agricultural as they may be, they're damn good at it. Bottom end torque is also pretty useful if you feel the urge to leave 50 foot long black stripes when you pull away!

There's no denying the mid 70s to mid 80s was a bleak time for American performance cars. They are completely strangled by emissions regulations, low compression, tiny ports, tiny valves, tiny carbs, and a catalytic convertor, smog pump and all sorts of rubbish. But, they are still a big engine which makes a decent amount of torque right from tick over, and binning all the restrictive save the planet accessories wakes them up a bit.

Fortunately by 1985 Chevy had developed a half decent fuel injection system, and while they were still "only" 200ish hp from 5 litres, decent spec Camaros and Trans Ams were doing 6 second 0-60 and 15 second quarter mile, despite being saddled with ridiculously tall gearing for better economy at cruising speed. Technology has moved on a lot in 30 years, but that was pretty impressive back then.