RV8s: Where do the 400HCs and 430s fit in?
Discussion
Trying to wrap my head around the Chimaera/Griff era V8s, and in particular their power outputs.
Irrespective of what figures TVR's engine guys might have claimed after they'd got back from the pub one Friday afternoon I gather the typical power outputs for the main engines in the real world is as follows...
400: 200-220 bhp
450: 240-260 bhp
500: 270+ bhp
What were the other variants (specifically those fitted to the Chim if there are any Griff-specific ones!) and how do they fit in?
Is a 430 closer to a 450 or a 400, for example? Are all 430s big valves and, if not, how much difference does that make? And where does the 400HC fit in relative to all 3?
Irrespective of what figures TVR's engine guys might have claimed after they'd got back from the pub one Friday afternoon I gather the typical power outputs for the main engines in the real world is as follows...
400: 200-220 bhp
450: 240-260 bhp
500: 270+ bhp
What were the other variants (specifically those fitted to the Chim if there are any Griff-specific ones!) and how do they fit in?
Is a 430 closer to a 450 or a 400, for example? Are all 430s big valves and, if not, how much difference does that make? And where does the 400HC fit in relative to all 3?
Despite the published figures for the 400HC, i get the impression this is just a slighty more revvy 400. I stand to be corrected, but i thought the actual power increase is minimal but had a different cam which allowed for higher revs.
My 400 will happily rev to 6250 rpm with no drop off in power and a lovely flat torque curve. The larger engined cars seem to lose power from 5.5k - but with the extra torque there is not so much need to take it to higher revs.
No idea about the 430, but i recall an article in Evo where Peter Wheeler said the 430BV was the best RV8. They are rare beasts and would be an early car (93-94?), but probably the most collectable of the range.
My 400 will happily rev to 6250 rpm with no drop off in power and a lovely flat torque curve. The larger engined cars seem to lose power from 5.5k - but with the extra torque there is not so much need to take it to higher revs.
No idea about the 430, but i recall an article in Evo where Peter Wheeler said the 430BV was the best RV8. They are rare beasts and would be an early car (93-94?), but probably the most collectable of the range.
Hi Chris
I think you're about right with those power figures; based on them being in good engine condition with no worn cams etc. They do really differ though dependent both on condition and also how they came out the factory. I don't think TVR were fanatical about engine blueprinting...but i may be wrong.
Re the 4.3 as an owner they are quite a bit more powerful than a 400...nearer a 4.5 i think. mine has been on rollers a couple of times (Austec on their original machine and then on their newer one which apparently is very accurate) Originally putting out 260bhp after a mnumber of differing minor mods it put out about 270 before going the uprated cam/rebuild and enlarged valves now puts out 300.
The main difference between all the 400s is that they rev more freely apparently (mine always has).
At the end of the day each car will be different and totally dependent on what state the engine is in.
Re the 4.3BV i'm no expert but my understanding is that they were all identified as such when they came out the factory...and were another notch up from the 4.3 in terms of power and tourque. most owners will know if they have a big valve and because of their rarety are worth more.
Not sure about the HC
Cheers
Lawrence
I think you're about right with those power figures; based on them being in good engine condition with no worn cams etc. They do really differ though dependent both on condition and also how they came out the factory. I don't think TVR were fanatical about engine blueprinting...but i may be wrong.
Re the 4.3 as an owner they are quite a bit more powerful than a 400...nearer a 4.5 i think. mine has been on rollers a couple of times (Austec on their original machine and then on their newer one which apparently is very accurate) Originally putting out 260bhp after a mnumber of differing minor mods it put out about 270 before going the uprated cam/rebuild and enlarged valves now puts out 300.
The main difference between all the 400s is that they rev more freely apparently (mine always has).
At the end of the day each car will be different and totally dependent on what state the engine is in.
Re the 4.3BV i'm no expert but my understanding is that they were all identified as such when they came out the factory...and were another notch up from the 4.3 in terms of power and tourque. most owners will know if they have a big valve and because of their rarety are worth more.
Not sure about the HC
Cheers
Lawrence
laz11 said:
Re the 4.3 as an owner they are quite a bit more powerful than a 400...nearer a 4.5 i think. mine has been on rollers a couple of times (Austec on their original machine and then on their newer one which apparently is very accurate) Originally putting out 260bhp after a mnumber of differing minor mods it put out about 270 before going the uprated cam/rebuild and enlarged valves now puts out 300.
So there's not that much work - particularly if you go by the assumption that they're old cars and may need cam changes etc. by now anyway - in getting a mildly tweaked 430 to perform with the best of the standard engines then?A friend of a friend used to own a 4.3 BV Griff and he was certainly of the opinion that it was the pick of the RV8 range. Obviously a bit biased though.
Coincidentally, there's one for sale (in Chim form) at the moment: http://www.pistonheads.com/sales/1583790.htm
Chris71 said:
laz11 said:
Re the 4.3 as an owner they are quite a bit more powerful than a 400...nearer a 4.5 i think. mine has been on rollers a couple of times (Austec on their original machine and then on their newer one which apparently is very accurate) Originally putting out 260bhp after a mnumber of differing minor mods it put out about 270 before going the uprated cam/rebuild and enlarged valves now puts out 300.
So there's not that much work - particularly if you go by the assumption that they're old cars and may need cam changes etc. by now anyway - in getting a mildly tweaked 430 to perform with the best of the standard engines then?A friend of a friend used to own a 4.3 BV Griff and he was certainly of the opinion that it was the pick of the RV8 range. Obviously a bit biased though.
Coincidentally, there's one for sale (in Chim form) at the moment: http://www.pistonheads.com/sales/1583790.htm
There's 430's and 430BV's... BV's were only officially used on the Griff AFIK. Lots of folks had the BV upgrade done or BV engines found their way into cars by mistake. If the car is over 260bhp it's likely to be a BV though?
Higher compression on the 430's is likely to make them a wee bit better than the equivalent 4.6's (TVR 450's) IMHO - the only ones of those I know that make good power have had a fair bit skimmed of the block to bring the pistons up the bore.
Higher compression on the 430's is likely to make them a wee bit better than the equivalent 4.6's (TVR 450's) IMHO - the only ones of those I know that make good power have had a fair bit skimmed of the block to bring the pistons up the bore.
I dont think it is that they are less popular, just they are features of the early cars.
The T5 gearbox used from 94 onwards is generally considered to be better than the SD1 - not sure why though. Could be smoother shift.
I've no idea of the benefits of the serp over the pre serp - most of the changes appear to be the cooling system. However, if you want to tune the car at some point, i would recommend getting a serp engined car, as it means you have the option of SC Power's supercharger conversion.
I have a pre-serp and unfortunately cannot go down the supercharger route - i'm not technical enough to convert the engine to serp spec. When i bought the car 7 years ago, the conversion wasn't around - would be a different choice had i been buying today.
The T5 gearbox used from 94 onwards is generally considered to be better than the SD1 - not sure why though. Could be smoother shift.
I've no idea of the benefits of the serp over the pre serp - most of the changes appear to be the cooling system. However, if you want to tune the car at some point, i would recommend getting a serp engined car, as it means you have the option of SC Power's supercharger conversion.
I have a pre-serp and unfortunately cannot go down the supercharger route - i'm not technical enough to convert the engine to serp spec. When i bought the car 7 years ago, the conversion wasn't around - would be a different choice had i been buying today.
I have a 4.0HC, when I first got the car I did some research on what the HC spec gave you.
Firstly it cost a new owner £1000.00 over the standard car which was quite reasonable on a car costing £30,000.00 plus, especially when you look at the extra power it promised.
I think the question is did it really deliver the power improvements it claimed?
I suspect not, but it is an improvement over the standard car as long as the cam is not worn, I'll come to that later.
HOW THE HC SPEC DIFFERS FROM A STANDARD 4.0:
1) 435 Cam (as per 5.0 litre)
Some say the 435 profile cam has a shorter life than the standard cam, once the 435 cam is worn in the HC any benefit over the standard 4.0 litre car is completely lost.
A healthy standard 4.0 litre car will always make more power than an HC with a worn cam.
All original TVR cams are a grind of the original Range Rover blank, perhaps the more aggressive grind breaches the hardening at a certain point on the lobe causing premature wear?
Or maybe the more aggressive profile itself accelerates the wear?
2) Pocket pistons
Pocket pistons remove the risk of valve to piston contact that would likely occur with the greater valve overlap produced by the aggressive 435 cam profile.
The pocket pistons also widen your choice of replacement cam.
3) Vernier adjustable cam sprocket and duplex cam chain
A useful addition that allows precise cam timing, however the adjustment can slip putting the timing out and removing any benefit.
4) Double valve springs
Double valve springs are there to reduce valve bounce at higher RPM, they do however also put additional strain on the valve gear promoting earlier wear.
5) HC spec ECU Chip
The HC chip has some amendments to the fuelling map and has the rev limiter set higher than the standard chip
OTHER 4.0HC CHARACTERISTICS:
1) Shunting
The HC is well known to shunt more than the standard 4.0 litre.
2) Revability
The HC should rev noticeably better and higher, again a worn HC cam will kill this
IS IT WORTH IT:
Now all these cars are getting on a bit I would suggest the focus should be finding the best example you can and not to get too distracted by the whole standard or HC spec thing.
As covered above a standard 4.0 in a good state of tune with a fresh cam will be a far better proposition than a 4.0HC with a worn cam that's a bit out of tune.
However>>>>>
If you get a good HC it can be a real peach, if it has a healthy cam and a tweak to the fuelling to solve the shunting a good 4.0HC is a revable delight.
Also because it gives you a much greater choice of cam profiles, if you want to go down the tuning rout an HC can make a lot of sense.
A Stealth cam and a set of Rob Robertson heads is where I am heading, until then my HC does me fine.
Firstly it cost a new owner £1000.00 over the standard car which was quite reasonable on a car costing £30,000.00 plus, especially when you look at the extra power it promised.
I think the question is did it really deliver the power improvements it claimed?
I suspect not, but it is an improvement over the standard car as long as the cam is not worn, I'll come to that later.
HOW THE HC SPEC DIFFERS FROM A STANDARD 4.0:
1) 435 Cam (as per 5.0 litre)
Some say the 435 profile cam has a shorter life than the standard cam, once the 435 cam is worn in the HC any benefit over the standard 4.0 litre car is completely lost.
A healthy standard 4.0 litre car will always make more power than an HC with a worn cam.
All original TVR cams are a grind of the original Range Rover blank, perhaps the more aggressive grind breaches the hardening at a certain point on the lobe causing premature wear?
Or maybe the more aggressive profile itself accelerates the wear?
2) Pocket pistons
Pocket pistons remove the risk of valve to piston contact that would likely occur with the greater valve overlap produced by the aggressive 435 cam profile.
The pocket pistons also widen your choice of replacement cam.
3) Vernier adjustable cam sprocket and duplex cam chain
A useful addition that allows precise cam timing, however the adjustment can slip putting the timing out and removing any benefit.
4) Double valve springs
Double valve springs are there to reduce valve bounce at higher RPM, they do however also put additional strain on the valve gear promoting earlier wear.
5) HC spec ECU Chip
The HC chip has some amendments to the fuelling map and has the rev limiter set higher than the standard chip
OTHER 4.0HC CHARACTERISTICS:
1) Shunting
The HC is well known to shunt more than the standard 4.0 litre.
2) Revability
The HC should rev noticeably better and higher, again a worn HC cam will kill this
IS IT WORTH IT:
Now all these cars are getting on a bit I would suggest the focus should be finding the best example you can and not to get too distracted by the whole standard or HC spec thing.
As covered above a standard 4.0 in a good state of tune with a fresh cam will be a far better proposition than a 4.0HC with a worn cam that's a bit out of tune.
However>>>>>
If you get a good HC it can be a real peach, if it has a healthy cam and a tweak to the fuelling to solve the shunting a good 4.0HC is a revable delight.
Also because it gives you a much greater choice of cam profiles, if you want to go down the tuning rout an HC can make a lot of sense.
A Stealth cam and a set of Rob Robertson heads is where I am heading, until then my HC does me fine.
Edited by Chimpafrolic on Friday 5th November 15:56
I saw four cars yesterday on a whistle stop tour of southern England. The 430 I drove first (cobalt blue one in the classifieds) went like a rocket. Easily quicker than the 450 I drove afterwards, but I think there may have been a combination of out-of-sorts 450 and a hot cam on the 430. Still, it graphically illustrated how they can overlap.
This is all a bit academic though as I've now bought a 500 (engine type had little to do with it, it was just a very 'tight' example with a chassis you could eat your dinner off...)
This is all a bit academic though as I've now bought a 500 (engine type had little to do with it, it was just a very 'tight' example with a chassis you could eat your dinner off...)
Slow M said:
Congratulations! I like the color scheme a lot.
B.
Thanks. The colour combination may be about to change though - I'm contemplating a switch to the regular 15/16" wheels in the near future. I'm slightly nervous about the handling characteristics of rubber band tyres on 18" rims front and rear. B.
It's a bit of shame because I was a real convert to the colour scheme when I saw it in the flesh. It's never going to be a traditionalist's car in bright yellow and the contrasting black wheels actually work quite well in real life.
Chris71 said:
Slow M said:
Congratulations! I like the color scheme a lot.
B.
Thanks. The colour combination may be about to change though - I'm contemplating a switch to the regular 15/16" wheels in the near future. I'm slightly nervous about the handling characteristics of rubber band tyres on 18" rims front and rear. B.
It's a bit of shame because I was a real convert to the colour scheme when I saw it in the flesh. It's never going to be a traditionalist's car in bright yellow and the contrasting black wheels actually work quite well in real life.
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