4.3 proper horsepower figures

[byron]

hi im reading that the 500s dont make any where near the tvr quoted horsepower figures has any one had their 4.3 dynoed and if so what true horsepower do they make my guess its not far off of the 500??

[mongoose]

As you probbly know,your going to open up a can of worms here!You would need to get two definately unmodified examples of each,on the same rolling road,and at the same time,to do any meaningful comparison.My guess is that the 4.3 pre-cat is 15 hp down on the 500,not much more than that,but others will surely have a different opinion

Edited by mongoose on Thursday 29th June 12:10

[vixpy1]

I've had 4.3's higher than 500's.. in the 270bhp's

[byron]

hi im not trying too compare the two just to get a realistic figure when mines ready i will have it dynoed, i would just like to know what they roughly make from the factory i know they say 280 bhp but as we all know these figures dont seem to be accurate

[petros]

Just had my 450 on the rolling road at Power. 275bhp, with engine blue printed, balanced,heads ported and new cam. Goes like a rocket.

[griffski]

For anyone interested these are the actual recent rolling road figures from my bog standard 4.3 which has 36,000 miles on the clock.

Max power speed @ 5341 rpm (112.5 mph in gear used)
Power at flywheel: 251 bhp
Power at wheels: 204 bhp

Max torque @ 3944 rpm (83.5 mph in gear used)
Max engine torque: 281 lb ft

Max mph reached in test: 124 mph
Max rpm reached in test: 5857 rpm

Ambient: 22'C
Baromic pressure: 1013 mb

[Ballistic Banana]

Hopefully after the Growl and maybe at another RR session at Vixys Place we can get some figures online to compare

[Griffter]

It'd be nice if the Growl RR saw a selection of engine variants

My 4.3 has been dynod in the past at 249bhp (Cheltenham - Power Engineering is it?). It's running a hell of a lot better now. If it's a real world 250 I'd be a happy man though.

Some back to back runs would be a good way to see what difference a BV spec makes too...

Edited by Griffter on Thursday 29th June 07:34

[stesrg]

griffski said:

For anyone interested these are the actual recent rolling road figures from my bog standard 4.3 which has 36,000 miles on the clock.

Max power speed @ 5341 rpm (112.5 mph in gear used)
Power at flywheel: 251 bhp
Power at wheels: 204 bhp

Max torque @ 3944 rpm (83.5 mph in gear used)
Max engine torque: 281 lb ft

Max mph reached in test: 124 mph
Max rpm reached in test: 5857 rpm

Ambient: 22'C
Baromic pressure: 1013 mb

Hmm thats interesting my 4.3 is modified heads ported , big valves , highlift cam, rhods lifters, adjustable push rods, epron chip, air flow mod, magnacore leads, and one or two other bits,, And now for the truth you all reading ................ TVR Power put it on their rollers 3 weeks ago and the power curve was as smooth as a ski slope the bhp figures

239 BHP .........

So what does that tel you all figures are bull sh*t. on the road its quicker than a 355 on accelaration I now this cus my mate has one ........

So were do we go from ere ?

I would say forget the figures its the nut behind the wheel that counts

[griffdude]

stesrg said:

I would say forget the figures its the nut behind the wheel that counts

Exactly...

[Tegriffic]

griffski said:

For anyone interested these are the actual recent rolling road figures from my bog standard 4.3 which has 36,000 miles on the clock.

There is a school of thought at Mid Essex that what you have there Glen is a BV that was not marked as such.
Does it SOUND like a standard 4.3 or does it have a deeper more unstable idle ?

[FlipFlopGriff]

stesrg said:

Hmm thats interesting my 4.3 is modified heads ported , big valves , highlift cam, rhods lifters, adjustable push rods, epron chip, air flow mod, magnacore leads, and one or two other bits,, And now for the truth you all reading ................ TVR Power put it on their rollers 3 weeks ago and the power curve was as smooth as a ski slope the bhp figures

239 BHP .........

So what does that tel you all figures are bull sh*t. on the road its quicker than a 355 on accelaration I now this cus my mate has one ........

So were do we go from ere ?

I would say forget the figures its the nut behind the wheel that counts

Seen you'd been on Steve. Glad to see you didn't have to sell up.
259.4 out of Mac and still rising (5,200)
FFG

[stesrg]

FlipFlopGriff said:

stesrg said:

Hmm thats interesting my 4.3 is modified heads ported , big valves , highlift cam, rhods lifters, adjustable push rods, epron chip, air flow mod, magnacore leads, and one or two other bits,, And now for the truth you all reading ................ TVR Power put it on their rollers 3 weeks ago and the power curve was as smooth as a ski slope the bhp figures

239 BHP .........

So what does that tel you all figures are bull sh*t. on the road its quicker than a 355 on accelaration I now this cus my mate has one ........

So were do we go from ere ?

I would say forget the figures its the nut behind the wheel that counts

Seen you'd been on Steve. Glad to see you didn't have to sell up.
259.4 out of Mac and still rising (5,200)
FFG

hmm nice what was the power curve like? if you get a ruler and draw a line at abour 35 degrees thats mine sooo smooooothhh

See you at the growl
Ps wifes gone. I got mi new house now no money
Ste .

[griffski]

Tegriffic said:

griffski said:

For anyone interested these are the actual recent rolling road figures from my bog standard 4.3 which has 36,000 miles on the clock.

There is a school of thought at Mid Essex that what you have there Glen is a BV that was not marked as such.
Does it SOUND like a standard 4.3 or does it have a deeper more unstable idle ?

That's news to me Shaun!
I looked at number of Griffs before buying mine, inc a couple of BV's. I remember the erratic idling which is mainly due to the different camshaft and that they didn't feel as smoooth to drive.

Original receipt and all service paperwork shows no reference to BV and I've spoken to the other 2 previous owners so I'm fairly confident it's a standard 4.3

I didn't think my RR figures were particularly high and it does depend a lot on the correct set-up and calibration of the testing equipment....



Let me know how your new manifolds sound?

[FlipFlopGriff]

stesrg said:

hmm nice what was the power curve like? if you get a ruler and draw a line at abour 35 degrees thats mine sooo smooooothhh

See you at the growl
Ps wifes gone. I got mi new house now no money
Ste .

Straight line as you say rom 1,750 (where it started) up to 5,200 (where they obviously give up) but it was still rising. Torque at 230 ish from 1,750, straight up to 277.4 at around 4,500 but over 250 from 3,200 right up to 5,200 (in fact it was 270 ish at 5,200 and not dipping much).
FFG

[pagej]

286hp @ 6000rpm, 280lbft @ 4500rpm on V8D's engine dyno

Larger plenum
Trumpet base
Ported intake manifold
Top hat liners (reused pistons + new rings)
Stage 3 heads
H404 cam
Everything else, injectors, ECU, dizzy, fuel pump & rail pressure etc the same
V8D clutch

Cost a small fortune and could have had more power, bigger engine etc for similiar money but I chose to keep with original capacity as to me 4.3's something special

Old engine was well shot even though it sounded OK, no rattles etc but cam was well rounded on two lobes, timing chain stretched, bearing shells down to the copper layer and worn bores, mind you 110K plus recorded miles so perhaps what you might expect...!?!?!

Look forward to meeting up with y'all at the Growl.

Do we have a Pre-Cat area yet...?

John