4.7 Litre and 550 HP !

[JensenA]

But it's a Speed 6 engine!
There's an article in Sprint magazine this month, reporting that Al Melling Sports Cars are offering rebuilds on the Straight 6's, with 2 options. A 4.5 and 4.7, giving 517Hp, and 550Hp respectively.
The cost? £7500.00 for the 4.5 and £8500 for the 4.7. and accompanied by 2 year parts and labour warranty.
Hmmmmm, interesting

[brakedust]

Yep, remember seeing this about a month ago, although most people commented that they didn't think it was possible? Would be good news if it was true though.
Anyone heard anything new about the AJP upgrade that is supposed to happening at about the same time?

[Nefarious]

Not wishing to cast aspersions on Mr. Melling, but some of his power claims are staright out of this chap's playbook:


Remember the one about the AJP making an extra 60bhp if they'd had another 3" of width in the cerb engine bay?

[lewis_sharman]

If you look down the bottom of the article it says the bhp figures are NOT estimates and were measured on a dyno

[Byker28i]

It makes a speed 6 cerbera look very interesting The article does say these are real figures from a customers engine, but I'd like to see a dyno graph.

Be very interesting to see what he can do with the AJP8.

[Brummmie]

Thats 117bhp/ltr, not impossible but it would need big revs to achieve that. So at what RPM was this meant to be?

[spitfire4v8]

the tvr power 4.3 makes 103hp/litre and only needs 6500rpm to do that .. assuming AM can get his airflow up he'd only need 7400rpm to make his target from 4.7 litres ?

[jesfirth]

Paul Edwards (one of the TVR sprinters) has just had his speed 6 rebuilt and rolling road mapped at TVR Power by John Ravenscroft yetserday. It is now 4.2litre and has 377BHP at the wheels at 7000rpm, give a say 20% margin for power loss etc that makes about 450BHP at the fly wheel which is brilliant - be interesting to see how long this one lasts. Paul is on his 7th rebuild in 18 months!

With the Al Melling offers remember a warranty is only any use if the company that offered it stays in business.

Edited by jesfirth on Thursday 11th June 20:33

[Brummmie]

spitfire4v8 said:

the tvr power 4.3 makes 103hp/litre and only needs 6500rpm to do that .. assuming AM can get his airflow up he'd only need 7400rpm to make his target from 4.7 litres ?

6500 to 7400rpm is a long way! I dont know how the engine is stretched, but if its stroked piston speeds will be even higher.

[BCA]

jesfirth said:

Paul Edwards (one of the TVR sprinters) has just had his speed 6 rebuilt and rolling road mapped at TVR Power by John Ravenscroft yetserday. It is now 4.2litre and has 377BHP at the wheels at 7000rpm, give a say 20% margin for power loss etc that makes about 450BHP at the fly wheel which is brilliant - be interesting to see how long this one lasts. Paul is on his 7th rebuild in 18 months!

Wow. Thats HUGE power!!

[rev-erend]

Come on BCA .. it's Melling they are talking about.

Pick of salt may be needed..

[JensenA]

For those who don't have Sprint. Here's a precis of what was written...

Cylinder head - Re-machined, re-positioned finger followers and camshaft, additional oil galleries, as per the original design.
New Valves, valve stem seals, Colsibro valve guides, New melling finger followers and valve springs.
New Solid Billet camshafts, with new profiles - as per the original design.
New Molybdenum disulphide impregnated Timing chain tensioner and new High spec timing chains.
New Solid Billet Crankshaft - as per the original design.
Re Bored Cylinder Block with Melling High performance Cylinder liners.
New melling Forged Pistons with custom High Spec piston rings and Dows D10 Dry lubricant to skirts.
New Forged H Beam 4340 Stell rods with ARP200 rod bolts. New Main and big end bearings.
New sump baffle and all new seals and gaskets.

All BHP figures are genuine Engine Dyno results obtained ffrom the development engine and are NOT estimated rolling road figures.

2 Year parts and labour warranty underwritten by Al Melling Supercars.

Quite a few references there to "as per the original design."

[Gazzab]

I am hopeful on this one, it would be great if Mr Melling could come up with a robust and powerful S6 engine. It seems TVR Power and STR8 (or whatever they are called) have the market tied up. Would also be good to hear more from Wilder?
Pistonheads hasnt been a great place for Melling of late and so I really hope he proves everyone wrong.

[450Nick]

Gazzab said:

I am hopeful on this one, it would be great if Mr Melling could come up with a robust and powerful S6 engine. It seems TVR Power and STR8 (or whatever they are called) have the market tied up. Would also be good to hear more from Wilder?
Pistonheads hasnt been a great place for Melling of late and so I really hope he proves everyone wrong.

I'm fairly sure Wilder is dead after a terrible display of reliability. They simply didn't solve the old problems from what I remember...

Now if Mr Melling were to revive the speed 12 design....! If he can get 550bhp out of a 4.7L speed 6, how much could he get out of a 9.4L V12??? Especially if the original speed 12 using TVR speed 6's made north of 900bhp originally? That would definitely be an engine on my xmas list

[BCA]

rev-erend said:

Come on BCA .. it's Melling they are talking about.

Pick of salt may be needed..

I doubt Paul has gone to Melling with his engine Rev. I also doubt TVR power would have anything to do with it... even if thier dyno seems a little melling-optimistic at times.

In all seriousness, from the sounds of things Pauls got between 400-450 REAL bhp out of his 4.2 six, thats HUGE power.

[rev-erend]

BCA said:

rev-erend said:

Come on BCA .. it's Melling they are talking about.

Pick of salt may be needed..

I doubt Paul has gone to Melling with his engine Rev. I also doubt TVR power would have anything to do with it... even if thier dyno seems a little melling-optimistic at times.

In all seriousness, from the sounds of things Pauls got between 400-450 REAL bhp out of his 4.2 six, thats HUGE power.

Sorry my misunderstanding .. though you was refering to the Melling claims.

[ro_butler]

Sorry to say this but I call BS on the Melling claims. He says a lot but never seems to be able to back it up.

Also 377bhp at the wheels is great but I am sceptical about 20% transmission losses on a 2wd chassis. Those dyno 'coastdown' tests don't convince me either.

As far as I know the only person who tested it even remotely properly was Simon Norris who ran the engine on an engine dyno and then in the car to get some idea of losses. Sadly it was an EVO so of no use to us, but I believe the losses were only about 20% ish.

[jesfirth]

paul has been handicapped for the sprint championship at 445 BHP based on the 377 at the wheels, it is standard formual that is used accross the board for all our cars to keep it fair.

[BCA]

Interesting. How did you all get on yesterday?

[jesfirth]

Hi BCA,
my car was a pain in the arse but just managed to squeeze out another win. In the morning I beat paul by 0.03 sec (very tight) in the afternoon I was about 1.5 sconds ahead.