New to V8 - Petrol and water queries

M

Mike Griffiths

New Member
Having just 'traded' from 4 cylinder auto to V8S, I need advice on two queries.

1. In the Haynes manual, it states that my car year model (1974) has a compression ratio of 9.25:1. If so can I run engine on RON95 petrol plus additive, or do I need an octane booster? At present car does not seem to 'pink' using this combination.

2. The car has been fitted with a Kenlowe fan. Should I remove the pump fan? If this fan should remain should the viscous fan revolve freely when cold? Mine seems to need quite a bit of force to rotate by hand, could it be faulty? Temperature gauge barely gets into centre section when at its warmest.

Any assistance would be appreciated.
 
Dear Mike,
I would say that not pinking is your best guide. If the additive that you are using (is it on the approved list?) plus unleaded fuel ( which does actually contain lead but only in very small quantities) is working for you then stick with it.
Second question - I have fitted a Kenlowe fan to my 1968 3500 as well as the original fan. I think (and have read) that the V8 engine in such a small place neeeds all the help it can get and that the Kenlowe is only there to get you out of trouble on a hot day or when stuck in traffic.
How have you got a viscous fan on a P6 ?
Regards, John (Glinn)
 
John

Thanks for the advice. At the moment I use the Shell additive, so I would suppose it's approved.

Regarding the fan, I believe that the V8 manual P6 has a viscous coupling as standard. Having spoken to a Jag' man at work, he say's that when cold the fan should turn by hand with a small amount of resistance. If this is the case then I probably need a new viscous coupling as mine's very tight when cold. I will also change thermostat as engine run's cold - verified by gauge and by touch, after 15 minute run. Could be thermostat stuck open.

Thanks again

Mike
 
Dear Mike,
FHBVC carried out tests on fuel additives submitted to them and approved only a handful. Shell was not one of them (I think).
As you probably know there are no standards for LRP which will disappear shortly anyway.
Try a search on "FHBVC" and select Fuel additive and the Rover P4 for some interesting (but slightly outdated) facts.
I use Castrol Valvemaster Plus with Super unleaded which is one of the cheapest (but approved) additives.
If you are fortunate enough to live near a petrol station which sells real 4 star you may be surprised to know that is 99+RON or almost 5 star! - Although it is very expensive but it will not disappear like LRP.
Regarding viscous fan - Should be fairly easy to get second hand example from scrapyard (plenty of SD1 V8 with terminal body rot) or an advert in P6 News may do the trick.
Good idea to change thermostat with total change of coolant every two years - Very cheap compared to engine damage!
Regards, John.
 
Another one to try is the shell optimax petrol, plus your favourite additive. optimax is 98+ and I know several people who swear it makes a noticeable difference to performance. :D
 
Hi.
I run a 1970 V8 fitted with a 9.35 compression engine with quite a few little 'tweaks'. I find Shell optimax the best fuel going, as Richard says it's 98 octane +, and use it in conjunction with either Castrol Valvemaster plus or Millers VSP. Both these additives are on the approved list and both contain octane boosters to help the fuel up to around 99 octane, or more if you use Optimax!
Leaded petrol is still available if you know where to look, I did publish a list of sites a couple of years ago in P6 News and Classics magazine always has a list in every issue. leaded petrol is supplied through Bayfords in the UK and there website www.bayfords.co.uk also contains a full listing of sites in the UK where you can buy it.

Hope this helps....and BTW send in an article for the Club magazine, I'm Desperate!!!!!

Bayfords website - leaded petrol

My Motor!
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Peter is right (as usual) but be aware that leaded petrol (as bought in Haverfordwest last summer was £1-09 per litre !)
I am between garages - about 30 miles one way and 25 the other which means it cost me two gallons plus just to fill up.
Regards, John.
 
Had filled up with BP unleaded a week ago and funny enough engine started pinking. When I filled up a few nights ago I actually did what Pete suggested, filled up with Optimax with above additive, and yes performance improved with no pinking, and better response. I will therefore stick to Optimax, and use Castrol Valvemaster, which I bought the other day. Regarding leaded petrol, there is a local garage that sells the stuff, trouble is its £1.10 per litre, so comparing cost, Optimax/Valvemaster works out at 80p/litre. A big cost saving as I use car on regular basis.

Regards

Mike
 
Dear Mike,

I'm glad this solution (no pun intended) has been acheived.
I also use Castrol Valvemaster Plus but have yet to try Optimax - Roll on the warm weather and my next tank of fuel.

Regards, John.
 
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