r911

My car wouldn't start after I went to the paint shop to collect it. It had been sitting for nearly a year so the gas is quite old - also it's pretty cold here now (40 oF). I called the guy who built the engine and he said to replace the spark plugs. It's a custom built 3.2L with dual plugged heads, rel. high compresion and mild street cams - with PMO carbs. It only has a few hundred miles on it (and due to a long series of unhappy events the engine itself has been sitting for a few years!).

So I pulled the plugs and they are Bosch FR-5-DTC top & bottom - 5/8" size with triple electrodes. I can't buy those here so I have to mail order them.

Now here's my question: I've heard that the newer Bosch platinum plugs are poor - esp. for carbureted engines. Not sure but IIRC, it might have been from Stever Weiner.

Since I have to order the spark plugs anyway, I am wondering if these are the new platinum plugs, and if so, should I perhaps buy something else?? I hate to second guess the engine builder, but OTOH he is in poor health and probably won't be tuning the engine up after it gets 1,500 miles on it anyway.

LongLiveThe3.2

You might already be planning on this, but you will want to get rid of that old gasoline as well. That might be a BIG part of why it won't run. It sounds like a fun motor!

senna21

Yea, after a year your gas is now varnish! Unless you put some gasoline stabilizer in there that stuff is just going to gum up your system. You need to drain it and put some fresh gas in there. I'd bet once that's done you might even be able to start it with the "old" plugs if they're not already fouled by the old gas.

Jay H

Randy,

I agree that after a year of sitting, that fuel is varnish and will really gunk stuff up. Old fuel burns worse than water. I've had motors that would not run for anything on old fuel. Draining the junk and putting in fresh stuff instantly cured the problem several times for me.

Good luck!

Jay
90 964

r911

I understand re the evaporation of the high volatiles. It won't technically be varnish yet, of course. The problem there is that I would have to take the carbs apart...

That's why I ask about the plugs, and whether I should use a different model. There doesn't seem to be a Bosch manual on their site to tell me if these are platinum or what.

KC911

If it were me, I'd talk to Steve directly (or John Walker, or one of the other knowledgable pros) and see what he/they recommend(s). I personally have gone the NGK route.

Keith

der Mond

Randy,
I'm no mechanic, so disregard what I am about to say. My experience with Bosch Platinum plugs in other vehicles has convinced me to never use them again. My experience with Iridium plugs (NGK in my case) has convinced me that I will always use them. I have Magnacor wires as well, and a APE chip, but I get 26 mpg+ consistently at 90 mph and that is 2 mpg better than all the 3.2's in a recent gas mileage thread. My motor starts, idles and runs wonderfully with them. This is really stretching it for this thread, but they have increased the gas mileage and performance of my snowmachine as well. In that case I have run a gap of .029 as opposed to the stock gap of .018, since Iridiums use less juice to fire, and it has transformed that machine. Ok, I'll shut up.
Dennis
P.S. By the way, 40 degrees is not cold, as you know. My 3.2 started and ran perfectly at -10 this morning. And RIGHT ON about getting rid of the old gas. Gas these days deteriorates quicker than ever. Another stretch
(sorry) - after two months, my chain saw will not start with the same gas....

Steve Weiner-Rennsport Systems

Randy:

Don't use Bosch platinum's in ANYTHING,... They are pure crap.

Use either Bosch FR5DTC's or W5DC's, or W5CC (silver) or NGK BP6ES.

If your car will sit, either over the winter, in storage, being worked on, its strongly recommended that you put some Stabil in the gas and run it for a bit. That will save you untold amounts of grief.

r911

Thanks much Steve. I take it the FR5DTC is as good as the others mentioned (?)

I would have used Stabil if I'd known.... I never thought the painter would keep the car so long. I also never thought it would take so long to find a lost tranny that a shop here had bought and then lost, or to find out that they got the wrong trans. ... I'm pretty sur ethe gas dates from the few miles I drove the car before taking it in to the painter (i.e. not from the engine build or tranny problems)

It's a long, highly frustrating story and I can tell you in person some time as long as you have a supply of Zoloft and some riot control items handy....

Thx again for posting.

Steve Weiner-Rennsport Systems

Hi Randy:

Yessir,..all that FR5DTC is a triple electrode plug made for long life in the 993's. It uses a 5/8" hex which is easier to slip by the head nuts.

Stabil is a godsend for ALL cars (and small engines) given the sad state of pump gas these days.

Zoloft is SOP around here,....LOL.

KC911

Steve, I use the NGK BP6ES in my '88, since I've always been happy with NGKs in my other vehicles over many years. In your opinion, how do they compare with the Boschs you suggested. Which ones do you use? Thanks!

Keith

ron mcatee

Based on Steve's recommendation, I changed to NGK BP6ES about 5 years ago and also put in the 8.5 mm Magnecores wires. My 88 Carrera has run exceptionally well since then.

Steve Weiner-Rennsport Systems

Hi Keith:

NGK's are truly excellent plugs and we use them interchangebly with Bosch ones, depending on the application.

You can't go wrong,...

KC911

Not as long as I/we have you pros keeping us on track!

imcarthur

Timely question . . .

I tried to buy to buy some NGK BP8ES (spec from manual or somewhere) & was sold BPR8ES. They told me the BP8ES are disco'd.

Are they suitable? 87 3.2 . . .

Thanks

Ian