Performance Cap and Rotor?

[btwilson86]

So it's almost time for me to start my Supra project, and I'm running into a dead-end on one of my parts searches....

I have an 88 Supra that I'll be putting an 89 Cressida 7MGE in, running that with the 88 Supra N/A electronics. Part of my project involves increasing the performance of the ignition system (and lots of custom wiring, yes!). I have everything figured out on how I will wire/install most of the components (wires, plugs, coil, spark control), but after several hours of searching the internet I am unable to find a performance distributor cap and rotor from a reputable manufacturer.

Does anyone know if someone makes a performance distributor cap and rotor?

Or does anyone have any experience with how long O.E.M. style components hold up to increased voltage?


Any info and input (except telling me to do a motor swap, I have my reasons) is much appreciated, especially if you can provide some links to what you've shared.

[cre]

I've yet to see an aftermarket "performance" cap and rotor which are actually what they advertise. Toyota's the most robust you're going to find... aftermarket makes are usually suspect to me. There are a LOT of people running high output, capacitive ignition systems on stock Toyota rotors and caps. YES, it's lifetime will be reduced, but you're not likely to cut it in half..... unless you've got something truly amazing planned...

Seriously though, if you're pushing enough current to destroy rotors and caps that quick you're wasting time and money... the STOCK ignition is solid enough to run most mods with no misses or partial burns. People put down over 400HP on turbo'd 4 cylinders running stock Toyota ignition systems.

What are you doing that requires so much more?

[btwilson86]

It's not so much that I'm planning on running alot of power through it, I have just been looking for a cap and rotor that will stand to what I'm assuming will be a higher voltage. I had my eye on an OEM cap and rotor from Toyota, just wasn't sure if they had any weak points I hadn't heard about.

All I intend on doing for the ignition system is the basic stuff:

MSD box (probably 6A-L, or may go with another brand that continues the multi-spark discharge to a higher rpm)
un-determined plug wires (likely MSD or ACCEL from a domestic V8 kit, probably 8.5mm spiral core or something similar)
aftermarket coil (once again thinking MSD, but still have more research to do on them)
NGK Iridium plugs

This part of the project is still in the R&D stage, as I'm running the stock ignition for the time being after my swap.

Limited cash up-front=multiple stage build

[cre]

Heh, I was going to suggest a MSD 6' as a possibility.... that or skip the rotor altogether and get a "points conversion" kit and go straight to COP. The stock rotor's fine for that system though.

My preference for wires are Taylor but you have to build them custom for your own app. They do make wires for domestic V8s (ONLY) but I prefer my wires to fit like a glove so I just buy the wire in bulk and build my own.

Forget the iridiums, they last longer but the material isn't actually as conductive as the less expensive plugs (copper and platinum)... they're a high mile plug, not really higher performing IMO. I'd go with NGK copper and see how they hold up; They're cheaper, work VERY well and you're not going to be upset if you find that the electrode on a $1 plug evaporated or the insulator exploded versus finding you need to replace a few iriduims after the first couple experimental drives. Platinum plugs are fine too, but don't get suckered into the boutique components because the manufacturer's say they're the greatest thing on Earth.

[cre]

I may not have made part of my point on the spark plug thing very clear. You may need to try a couple different temperatures of plug before you find the "right one", start with the stock 5's. If you're bumping the timing up to or past 15 degrees BTDC then step to a 6. Check the plugs frequently for signs of detonation and fouling and replace with another temp as merited.

[btwilson86]

Alright, that's the kind of info I've been looking for! On the plugs, I had just kinda assumed more $=better plug, makes sense what you're saying though. I'll probably start with either the basic coppers or V powers. Benefit of working in the business, plugs are cheap :P

So maybe you can help me out on the plug wires... The whole point of this is to get more energy overall, and as much as possible to the plug for the best spark. So you say Taylor's over Spiral Core, what's your reasoning? Are they more conductive? I'm gonna go spend some time on Google and see if I can find some sites with good info and link back here with what I find (if anything).

Thanks for the input cre

[btwilson86]

Whew, never thought that trying to find a decent comparison of wire construction would be so difficult...

I did find some halfway decent info about some ACCEL wires from their website, but most of their wires are all spiral-wound construction and don't differ much, if any. I did read on a couple of forums that the "Ohm resistance check" for plug wires doesn't have any real world use. This is supposedly because the voltage during this test is using 1 Volt Direct Current (DC), and DC voltage finds the path with least resistance traveling through the wire. Apparently ignition systems produce Alternating Current (AC) from the coil, and AC current travels around the wire instead of through it. Therefore lower resistance through the wire doesn't matter as much as a lower resistance on the outermost wire. Keep in mind I'm not an electrician, so I'm not sure how true that statement is. In any case, still haven't found any wires, so I'm still working on that part...

I may have found a coil, thinking of using the ACCEL Ultra Coil by Jacobs, found here. It seems most aftermarket ignition coils run in about the 40,000 volt range, and this one's rated at 55,000 volts. Anyone have an idea of what the factory coil's output voltage is rated at? I'd like to have something to compare to while looking up coils...

And if I didn't state earlier I'll be using Genuine Toyota cap and rotor.

As for the plugs, I'll experiment around with NGK's, starting with the factory resistor plugs. I'll probably play with heat ranges and composition (platinum, double platinum). May even try the E3's, although I'm not sure how the engine would like little flamethrowers in the combustion chamber (especially with higher voltage and current).


For those reading this and want to know, my goal after I have accumulated enough money for the rebuild is to run a de-stroked, .020 over, high compression N/A 7M in a substantially lightened Supra hard-top. There will be alot more mods to go with the ignition system, including an ecu (not sure on standalone or piggyback), but I intend to run this ignition system on the stock engine for now for a mild performance gain. I believe it will have a much greater effect down the road on my build.

EDIT: Just spent quite some time over at supramania reading Aaron's "5M Crank in a 7M" build thread regarding a de-stroked 7M... Lots of good info there, looks like running a modded 7M crank is the way to go instead of the 5M crank with extended snout. Not sure how I'll go about piston rods though since his build was for a boosted 7M and I'm goin N/A. Anyway, that's all I'll say in this post since the thread is about a performance cap / rotor with some ignition system info.

[cre]

Build your own wires... if you get a performance set make sure they're resistance wires, EFI doesn't play well with the interferance you'll get from dropping a set from a '67 Malibu in there.

Agreed, 5M is not the best choice.

Go standalone EMS... can't change the rev limit on the stock ECU.... well, you can hack it and reclock the board but it throws everything else off.

E3's..... never tried them, but given the horror stories I've heard and a photo of a piston with bubbling in the center I don't think I'd run them in my lawnmower.... especially not on a healthy car with a HEALTHY ignition system.... great for cars where everything else has been neglected, I'm sure. This isn't something I'd experiment with myself; the amount of labor involved to fix it if such a cheap part fails is too high.

[btwilson86]

Yeah, I was thinking I'd have to run something along the lines of an AEM EMS, but I haven't looked too far into that as the project is still a long way down the road. I happen to have a complete 4M in my garage, perhaps I'll play around with that and see what I may be able to use for my build. Not sure how good or bad the internals are on that, or how beefy the bearing caps may be. I suspect they aren't going to be suitable for my needs, but I won't know till I tear it apart!

From the beginning I knew I would have to build my own wires, I don't have the #3 cylinder head cover so all 7M specific sets wouldn't look or fit right anyway. I'm leaning towards running a set of spiral wound set of MSD 8.5mm's, they claim to have excellent insulation for EMI which I understand is what makes many wires unsuitable for computer controlled vehicles.

As for the E3's.... I've heard MANY mixed reviews on them; many good, and many bad. However, from what I've seen so far I haven't heard anyone complain about such a substantial problem as melting pistons. Granted, that was just an idea I threw out on here and I haven't done much dedicated research on the plugs yet. Cre, you have mentioned before that you acquire much of your knowledge from talking to and listening to reputable mechanics and Supra enthusiasts, so I'll take your warning on the plugs very seriously. I'm back to thinking of starting with some good ole' fashioned NGK's.

[cre]

when it comes to the E3s I don't think any damage us entirely the plugs' fault... I think people are running the wrong temp and the wrong gap. I duo think they move the kernel too farout.

I am also of the mind that 99% off those who see improvement have other issues which are just being covered up.