The Rally Maestro project

[Guest]

Tony Fowkes wants to replace the hose from the filler-pipe to the petrol tank, its 26 cm long, and 4.5 cm internal diameter. Any suggestions? Am about to browse Car Builders Sollutions parts-brochure (www.nfauto.com ) as they are quite good on piping, as the original is 1986 I guess Tony is thinking its time it was replaced, and, reinforced in the vulnerable areas.

The long-range tank now has its own fuel pump. Phew, was wondering how gravity was supposed to empty it all...

[E_T_V]

But bearing in mind the low milage I'd be suprised if the servo was at fault. The master cylinder either works or it doesn't really and these are generally reliable too so long as the brake fluid is clean.

[E_T_V]

The fuel filler pipe rarely if ever gives problems. I'd be tempted to leave it as is, but perhaps wrap it in something to protect it if you think it is vulnerable (I don't think it is too bad).

[Guest]

It seems nobody races a 1.6 these days.

... Anyone recall what the best spark plugs should be?

[G Force]

It seems nobody races a 1.6 these days.

... Anyone recall what the best spark plugs should be?

My recomendation would be NGK BCPR6EY-11

I would say even more important than plug type is the plug lead quality, NGK or Magnecor leads are a must especially if you encounter any water crossings.

[Chris Y]

Racers tended to use the BPR 7EY - slightly 'hotter' plug.

[G Force]

Racers tended to use the BPR 7EY - slightly 'hotter' plug.

Hi Chris, It was probably a typo but to avoid confusion, for the 1.6 S series it has to be BCPR type, the BPR does not have the 5/8in hex size it has the more standard hex 13/16in which doesn't allow enough clearance between cylinder head & hex for a standard plug socket.

Also I think I know you mean the racers use 7 heat range instead of 6 as they may have engine setups with slightly more power than standard and could overheat & damage a standard plug. The 7 is fine but is actually a colder plug than the 6. (cold plugs for hot engines). (hot plugs for cold engines)

The NGK heat numbering system is the oppersite way to say the champion heat number codes. N12Y being hotter than an N9Y

I would say a 6 would cover any mild tuning mods that could be done to an S series on a single carb, but if your race car on webbers had problems with plugs overheating & cracking a 7 might be better suited.

Regards, Gary

[Chris Y]

Hi Chris, It was probably a typo but to avoid confusion, for the 1.6 S series it has to be BCPR type, the BPR does not have the 5/8in hex size it has the more standard hex 13/16in which doesn't allow enough clearance between cylinder head & hex for a standard plug socket.

It wasn't a typo! I used the BCPR, but I know many of the other 1600 racers used the BPR, and used a spanner or specially adapted socket to access them. The head from the blue race car I have has lots of scuff marks around the spark plug holes where such a tool has been used.

Also I think I know you mean the racers use 7 heat range instead of 6 as they may have engine setups with slightly more power than standard and could overheat & damage a standard plug. The 7 is fine but is actually a colder plug than the 6. (cold plugs for hot engines). (hot plugs for cold engines)

Yeah, got that the wrong way around, as usual!

For a rally car such as we're discussing, the 6 plugs should be fine, but I was filling people in on what the racers used.

[Guest]

Interesting stuff. But shouldnt I be using a plug that uses a conventional plug spanner....thinking of downtown Africa, and what is used by bush-mechanics. Was thinking someone on here would suggest a platinum plug?

The car is essentially standard, although Peter Burgess reckons his cylinder head work (without raising the compression ratio) on a standard carb (ok, an HS6 earlier one, but new, for simplicity), will be around 100 bhp. Optimistic? I told him Im a bit surprised at this, and he said dont be, "call me when you are on the rolling-road sorting it." He reckons the S-head releases a significant improvement in power once its breathing a bit better - we shall see.

We have also cleaned up the immediate area of the downpipe, there is a ring of weld inside, and this has been ground back a bit, and the mounting plate at the top reinforced with some additional tack welds where it joins the downpipes. With over a quarter-inch of weld sticking out inside the pipe, its benefited by a bit of flowing and is now less restrictive. The rest of the exhaust has yet to be sorted, but after the bit where the two pipes become one, there is going to be a new bit of flexi-pipe inserted, and a free-flow two-inch system through to the rear.

[G Force]

Interesting stuff. But shouldnt I be using a plug that uses a conventional plug spanner....thinking of downtown Africa, and what is used by bush-mechanics. Was thinking someone on here would suggest a platinum plug?

.

You could use platinum or iridium if you wish but the gains will be minimal if any for your application. The EY plug has a nice robust V grooved centre electrode for a good concentrated spark. Reletively inexpensive so you can carry a spare set. Good quality leads and these plugs will give consistantly good performance over the rally.

A nicely ported head can give good gains over standard. Even just cutting a nice 3 angle seat will improve performance & drivabillity. The gains may not be significantly higher at full power but mid range can see the best improvements. Attention to the little things like the exhaust is well worth the effort, all the gains add up.

[Guest]

Thanks for that. Just so there is no misunderstanding - whats the code-numbers of the plug I need to find, will go into Halfords later.

The exhaust downpipe has a horrible constriction where the two pipes at the down-end are quashed, before it goes into one. This looks like a definite bottle neck when you peer down the bottom end of the pipe... Any suggestions?

[G Force]

Thanks for that. Just so there is no misunderstanding - whats the code-numbers of the plug I need to find, will go into Halfords later.

The exhaust downpipe has a horrible constriction where the two pipes at the down-end are quashed, before it goes into one. This looks like a definite bottle neck when you peer down the bottom end of the pipe... Any suggestions?

NGK BCPR6EY-11 If you can't get those use the standard gap, NGK BCPR6EY


With regards to the exhaust, all you can do to improve that situation is to cut the collector off, open the down pipes and fit a custom made collector, or have a stainless front pipe custom made.

[Guest]

Halfords had both types of NGK on their hooks, so got the ones with the 11 on the end, presume these are the same plugs but the one with 11 after its part-no has a fraction more gap for a fatter spark?

Next up is a set of leads. Given its Africa, do we just chuck caution to the wind and get some old fashioned copper core jobs and upset everyone's TV on the night run to Dover...or, is there something as good but less anti-social? If so, where from? There are "twin spark" leads promoted at Euro-spares. Is this a gimmick? What leads have proved best on the circuits?

[G Force]

Hpresume these are the same plugs but the one with 11 after its part-no has a fraction more gap for a fatter spark? ?

Yes thats correct, you can still set them to the recommended 0.040in (1mm) their is less chance of quenching of the spark with the longer earth electrode.

Next up is a set of leads. Given its Africa, do we just chuck caution to the wind and get some old fashioned copper core jobs and upset everyone's TV on the night run to Dover...or, is there something as good but less anti-social? If so, where from? There are "twin spark" leads promoted at Euro-spares. Is this a gimmick? What leads have proved best on the circuits?

Don't choose copper core leads as they don't have enough resistance, a better quality spark is achieved with resistive leads and plugs.

Magnecor leads are by far the best, although expensive they represent good value for money (8mm minimum). NGK do 8mm leads which are less expensive but decent quality. "twin spark"? don't know but if they are cheap to buy they won't be great.

[Guest]

Called up Magnecor,after finding them on the 'net, they were happy to offer a good discount, having got some Rover-Maestro plug-leads in their catalogue they were on the shelf. Got onto Jetex exhausts bits, and got a Y piece coming tomorrow that hopefully will sort the horrid squashed bit of the two pipes forced into a single pipe, theirs opens out to a 2 inch single pipe, and maybe this can be made to fit, it ought to offer a real benefit given its clearly a real restriction in flow.

Got the NGK plugs with the 11 on the end - do I presume they are gapped up ready to fit, straight out the box, not requiring anything on the fitter's part? Head has been done by Peter Burgess now (alas, after firing up the cattle-prod with a good dose of nagging), and the head is being collected tomorrow by Peter Banham to shim up. (New inlet valves having been found - failed to find any new valve-springs, and also failed to find any new exhaust-valves). Hope this is a straight forward job!

Thanks to g-force above for all the advice.

Hopefully, we will fire it up next week. Talking of g-force, does the engine by his signature rock and roll like that because the engine-mounts are shot? Hmmm, thats worrying. What's the solution to stop excessive engine-rock on rough roads damaging the mountings?