Rover V8 question

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DonkeyApple

Original Poster:

54,923 posts

168 months

Monday 20th April 2015
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Back in 2010 I bought a classic Rangie that had a new RPI 3.5 engine in it. It's on carbs and all I know is that it was built with hotter cams and to a spec normally used in kit cars like Cobras.

Now, I've only driven the car once, back in 2011 and it's been in storage since.

The chap who is starting work on it soon took it out for a drive a while back and in a passing remark he reckoned it must have approaching 200 bhp given its performance.

Now it's a very, very sweet engine and certainly revs more freely than a standard Rangie unit which gave 135 bhp in standard carbed form.

So the question is, whether a figure like 200 is plausible for a hot but not particularly special 3.5?

ChilliWhizz

11,990 posts

160 months

Monday 20th April 2015
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DonkeyApple said:
Back in 2010 I bought a classic Rangie that had a new RPI 3.5 engine in it. It's on carbs and all I know is that it was built with hotter cams and to a spec normally used in kit cars like Cobras.

Now, I've only driven the car once, back in 2011 and it's been in storage since.

The chap who is starting work on it soon took it out for a drive a while back and in a passing remark he reckoned it must have approaching 200 bhp given its performance.

Now it's a very, very sweet engine and certainly revs more freely than a standard Rangie unit which gave 135 bhp in standard carbed form.

So the question is, whether a figure like 200 is plausible for a hot but not particularly special 3.5?
'hotter cams'? must be a typo RV8 has a single cam wink

Short answer, (IMHO) a hotter cam and carbs on their own won't give you 200bhp from a 3.5 When you say carbs are we talking twin SU's? I have a set of SD1 heads (bigger valves than the earlier 3.5's)in my workshop which I bought when I had my BGT V8, with the intention of modifying the old factory 3.5 lump (I even have the newer MGB RV8 tubular exhaust manifolds still) of course its possible that an RPI built lump has had lots of headwork, high compression, port matched inlet and exhaust manifolds etc, but it'd have to be a bit special to produce 200bhp if it's on twin SU's with a dizzy with a boggo RR exhaust system... Also, the RPI lumps built for Rangies are stump pullers, but if it's been built for a light kit car it might have been built with the focus more on power than torque.. (as my V8D lump was)

All in my humble opinion of course...

DonkeyApple

Original Poster:

54,923 posts

168 months

Monday 20th April 2015
quotequote all
ChilliWhizz said:
DonkeyApple said:
Back in 2010 I bought a classic Rangie that had a new RPI 3.5 engine in it. It's on carbs and all I know is that it was built with hotter cams and to a spec normally used in kit cars like Cobras.

Now, I've only driven the car once, back in 2011 and it's been in storage since.

The chap who is starting work on it soon took it out for a drive a while back and in a passing remark he reckoned it must have approaching 200 bhp given its performance.

Now it's a very, very sweet engine and certainly revs more freely than a standard Rangie unit which gave 135 bhp in standard carbed form.

So the question is, whether a figure like 200 is plausible for a hot but not particularly special 3.5?
'hotter cams'? must be a typo RV8 has a single cam wink

Short answer, (IMHO) a hotter cam and carbs on their own won't give you 200bhp from a 3.5 When you say carbs are we talking twin SU's? I have a set of SD1 heads (bigger valves than the earlier 3.5's)in my workshop which I bought when I had my BGT V8, with the intention of modifying the old factory 3.5 lump (I even have the newer MGB RV8 tubular exhaust manifolds still) of course its possible that an RPI built lump has had lots of headwork, high compression, port matched inlet and exhaust manifolds etc, but it'd have to be a bit special to produce 200bhp if it's on twin SU's with a dizzy with a boggo RR exhaust system... Also, the RPI lumps built for Rangies are stump pullers, but if it's been built for a light kit car it might have been built with the focus more on power than torque.. (as my V8D lump was)

All in my humble opinion of course...
They've got 16 cams. You're thinking of the camshaft. wink

I reckon 200 bhp is very adventurous. Especially as you say the engine, in theory, should be trading bhp for torque in a van.

The later flapper 3.5s gave 165 so it's hard to see a carb setup bettering that without giving up torque and being pretty useless.

ChilliWhizz

11,990 posts

160 months

Tuesday 21st April 2015
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Any piccies of the Rangie? I had a two door back in '86 when we lived in Devon smile

carsy

3,018 posts

164 months

Tuesday 21st April 2015
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I put a bog standard 3.5 rv8 in a kit car i built when i was 18. Going back a while but anyway that produced 170 at the wheels. All it had was a mild cam and a Holley 390 carb.

DonkeyApple

Original Poster:

54,923 posts

168 months

Tuesday 21st April 2015
quotequote all
ChilliWhizz said:
Any piccies of the Rangie? I had a two door back in '86 when we lived in Devon smile
Page 2 has some of the body resto images and how it currently looks.


http://www.pistonheads.com/gassing/topic.asp?h=0&a...