I understand that I'll have to set the vacuum advance with a little bit of trial and error and testing. That's no problem. I did check my stock distributor previously, and it advanced 5-6 degrees at around 10-11" vacuum. I have no idea if that is normal, and seeing how rusted the pivot was in my distributor, it may not have been moving fully.

What I was more curious about was what was my stock distributor curve, and where should it be set with my newly rebuilt engine specs. So it looks like Ford intended my old 8.3:1 compression 302 to have 8 degrees initial advance, and 44 degrees total coming in by 4500 RPM, assuming everything worked the way it was supposed to.

Assuming my rebuilt engine with the GT40 heads comes in between 9.1:1-9.5:1 compression, what I'll need is 38-42 degrees total advance coming in by 2500 RPM. That gives me a ballpark on where I want to be, and that's fine.

Now that I know how to do it, making changes won't take much.

 

Just out of curiosity, what MSD box are you referring to? Would it replace the DSII box on my fender liner, or be in addition to it?

The engine shop said they'll be using an MSD box for the dyno work, and that I'll have to re-adjust my timing when I get the engine back in the truck.

 

It would be in place of the DSII box.
They should make a harness to make it P&P.


What I like of the MSD, I run the full set up on my drag car, is you can add different things (timing retard, rev limit, etc.) later if you want.
Dave ----

 

Start a little lower of total advance, with the GT40's fast burn chamber will like a few degrees less. I think you will end up in 34-36 range to be honest.

 

Yup the MSD box will replace the DS II box . Ask the shop what MSD box they are using on their Dyno and or what they recommend. MSD does offer a duraspark dist pick up adapter so you do not have to splice the pick up wires.

 

You can hook the MSD box up two different ways;

1. You can keep everything you have original, and let all the original Ford stuff trigger the MSD box instead of the coil. Then the MSD box will fire the coil.

2. You can buy a short harness and plug that in to the Ford dist and the other end goes to the MSD box, so the Ford dist triggers the MSD box directly, and eliminate the duraspark II box.

MSD has a good website and you can download their instructions, they have instructions for all the different makes.

 

Ya I never understood why one would do this I can't think of a single application where this would be a benefit in a DSII system. Add the MSD and add bunch of wiring. All it does is complicated the ignition circuit.
The only time I could see this being done would be in a totally stock application for emissions compliance inspection.

 

Some new SBF parts arrived today, one of which was a new timing cover.

I was checking it out, and the two bottom holes that are enlarged for dowel sleeves, seem like they're a hair too big (The dowels are a little loose). I don't have my old cover to compare, but I didn't think that they were loose.

I was doing some reading, and I found some guys saying that some SBF's didn't even have these dowels, and that the cover is usually aligned on the snout of the harmonic balancer? Or, that some engine machine shops have a specific alignment tool for this?

I guess my question is: Does it matter if the dowels are a little loose? Or should I send the cover back and buy different one?

 

Just install them in the block first. The dowels are there to help align the harmonic balancer seal if you speed sleeve the balancer you will have a little variation to play with.

There is tool to align the cover to the crank but I have never used one and have never had a problem with leaks.. But your millage may vary.

 

Well these heavy hunks of GT40 iron finally arrived today. They are F3ZE-AA castings, but not drilled/machined for thermactor ports, so according to my web searches that means they're from a 1996 or early 1997 Explorer. There are reports of the Mustang guys pulling these off of Explorers, so that's fine.

I'll have to CC them, but according to internet folklore, these castings were milled an extra couple passes for the Cobras to get the chamber size down, but left alone for the Explorers. I guess we'll see what size they are.

In any case, they look WAY better than my old D8OE heads!! I won't have fancy aluminums, but that's OK...the heavy old school irons are fine for me.

 

Nice looking set of heads, it will be interesting to see what they CC out at.

 

Another dumb SBF question(s)...

I need a new coolant temperature sensor for my factory gauge. They're available from Ford for $80 bucks, or aftermarket for $65 (premium) or $23 (Economy).

Will the econo sensor work OK for this, or do I need an expensive one?

Also, if I install an aftermarket gauge set, with one of them being coolant, where would I install the second sensor?

Any comments good or bad?

 

Spending that kind of money on a factory gauge sensor would be a total waste. I would spend my money on the aftermarket gauges. Don't even hook the factory one back up. You can use simple plumbing tees and fittings to hook both oil pressure sensors up, but the temp sensor probe needs to be in the flow path of the coolant. So it's more difficult to locate both coolant sensors, simple tee fittings won't work.

 

What intake manifold are you going to use?
Some after market ones have 2 ports in water jackets but if not then as Dave F said just run the aftermarket gauge.


Just thought of something. I have seen radiator hose fittings that you can put a gauge in. You cut the hose top or bottom, slip this fitting in and 1 clamps to hold it, screw in the sender into this fitting and you now have a 2nd sender.
Like this but don't know if it is the right size.
https://www.summitracing.com/parts/hre-3436/overview/

Dave ----

 

Oh...that would bug me too much. I need the factory gauge to be functional, even if it's not accurate. If I only had an idiot light, then yes, I could have it be non-functional, but an actual gauge will bug me if it's dead.

I have a new Edelbrock Performer 289 intake. I believe it only has the one port which is either 1/4" or 3/8" NPT. I was wondering about a tee in the coolant line, that might be an idea.