Correct fuel for High Compression Pinto

mormj001 · 01-03-2010, 03:01 PM

Looking for the correct fuel to use in a high compression (10.5:1) 2lt Pinto. My RS MK2, 2 door has been in storage for 8 years now so I am unsure what to do to get it back on the road now that leaded is no longer available. Bottom end has had a lot of work with max bore and oversized pistons and the head has been ported and polished (flow 185hp) with large oversized valves, BP300 cam, vernier etc. It currently only has a double throat capri carby installed with the intention of twin 45 webers (as a minimum) to go on soon.

Last time I looked, the 'fuelstar' system (tin replacement) was recommended but are there alternatives or does the 'fuelstar' system actually work?

The last time I drove it, it was still pinging with leaded and octane booster under load. I am sure someone hear has found a solution.

My very first post so any help will be mcuh appreciated.

Mick

JamesR · 01-03-2010, 04:07 PM

98ron should be fine, might need to get it retuned though.

2lt_Scort · 01-03-2010, 08:25 PM

G'Day Mick,
I run two different Pintos one 11:1 with no pinging probs and latest I've built is around 11.5:1 (similar spec to yours) which isn't liking too much timing on pump fuel and octane booster. Running that one on a 38DGAS at the moment, have backed timing off and blocked vac advance to stop pinging until run in then will get it tuned properly.
But at 10.5:1 you shouldnt be having any problems if tuned correctly. Premium unleaded should do the trick.
Or you could opt for the ethanol based stuff, some of it has a 100 ron rating I beleive but over here in SA its at very few stations (none of which are close to me).

mormj001 · 02-03-2010, 10:49 AM

Thanks guys,

So, there is no need for a lead replacement to ensure the valve seats survive?

That was my only concern and I am assuming the old pinging issue will be resolved due to premium being a higher octane than the old leaded petrol which is a bit of a bonus. If I manage to find the ethanol at 100ron then all the better by the sounds of it.

In theory, anyone have an idea as to what will happen to the power output with the premium compared to the leaded?

Also, If my compression is higher than 10.5, does that affect anything mentioned above? I have a sneaky impression it may be higher but I just can't remember the exact figure.

outback_ute · 12-03-2010, 11:23 AM

Valve seat recession will be an issue without the lead. You may get away with it for a while as I understand there is a residual effect. Make sure you keep an eye on valve clearances, and if/when the head is off take the opportunity to have valve seat inserts put in.

T3man · 18-03-2010, 09:09 PM

Yes you definitely need some lead replacement.

I tried for years to get my RS2000 to run on various mixes of premium unleaded including 98 and 100 and also with octane booster and lead replacement - gave up in the end and just converted it to straight LPG. Still use lead replacement and that's all it needs.

WOW - all the old performance came back! It was so good I converted the Capri GT3000 as well. What a blast to drive now!!

mormj001 · 19-03-2010, 04:03 PM

I want to keep it naturally aspirated so it sounds like performance will be poor even with the twin 45's.

Is there anyway to get AV Gas in SA these days?

feral · 19-03-2010, 05:35 PM

I'm not sure of the deal with av gas, but OG Speed shop used to sell it, you could give them a call.

Puzzlescort · 20-03-2010, 07:48 AM

Mick

Av Gas is still around...for track work AVgas is still allowed in some classes, illegal for the road

:

I use JFP 100 racing fuel in the Escort with 11.2, the old motor was 10.5 which used BP ultimate 100 or what ever it is with a lead additive.
The key is as we found was the tuning, when we stopped using Avgas we had to completely retune the car. it still pinged on hot events under major load but still was drivable

get it down to a good tuner & stick it on the dyno - only way to get it sorted!