i'm proud to say i've completed my CAI, muffler, and cat converter mods, and i love the way bonnie is moving and sounding! it has been worth every penny so far. the question is what should i do next? an intense pcm seems to be the logical choice, but what about rockers or a cam? i'd also like to hear what you guys think about computer mods other than getting a whole new unit. what are the best chips out there, and what do they do differently than intense'* comp? maybe i'd even get the software to flash the pcm and choose my own parameters. what say you?

you havent done headers yet...so thats still an option...i noticed domestic performance had some sort of wierd computer programming type deal for the 97 and up so you might check that out as well....you could also get a new ignition and coils if you wanted to make the most out of what youve got.....

mmm...Like LittleHoov said, you should probably go with headers first. The nature of mass production on a relatively complex piece like the exhaust manifold ruins any chance of proper exhaust flow. Save your money on the coils, they have 3.8'* running 11'* on stock coils. You should also probably save computer mods for one of the last modifications or after a large change such as a high-lift cam.

Gotta clarify something here.....the 97 and newer SSEi and GTP got a hotter coil from GM than the other models. Upgrading to this coil may benefit. It'* basically the same thing as the MSD 8224 in 'hotness'.

So if you have an 87-96 Bonneville (any model, but 87-92 must convert to delco II ICM first), OR a NON-supercharged 97-2004 (excluding GXP), the 97+ SSEi coils or MSD 8224 will give you a stronger mid/high rpm range punch.

Not a HUGE punch, but it can be felt (maybe 5-7hp?) You must have wires to support it, and might be better served to wait until a stock coil fails before you upgrade.

damn you! I was just gonna say the same thing!

PCM = last, that way you can have EVERY mod programmed in for maximum performance, you do want maximum performance, right?

Adding - if you light off all the fuel, you get better mpg.. just because the fuel is there, it just wants to be lit off.


-justin

This might be one of those "who knows?" things but my opinion is a little different. Lemme explain, and I'm still learning this so tell me if I'm off...

Because both the stock and MSD coils have a turns ratio of 80:1 and obviously have the same voltage input the output for both is fixed at 40,000v. This is why installing an ignition control module ups the voltage to 45,000v; larger input voltage.

The other issue (actually benefit) is the DIS systems is whats called a closed loop dwell control system. The ICM keeps track of the coil buildup to ensure the maximum current was attained (6-8amps I believe *?*). If it is the dwell time is cut short to release some load on the system. If not its lengthened. So basically no matter what you put on there the current will remain about the same as well as the dwell time.

Another misconception about the system is that the power is reduced at higher rpm'*. This is something that was carried over from the old distrubitor points system where at higher rpm the "contact" is made for a shorter time. This isn't an issue with the DIS systems and its one of the reasons it was implemented. The only issue is with the charge time of the coil, which lucky for us is in the 10-200microsecond area.

The resistance in the MSD 8224 coils is about the same (because of the equal length of windings) as the factory system so there really isn't much of a benefit there. They rate their primary at .35 ohms while thats the lower end of factory ratings. This is probably just an advertising thing as GM could technically say theirs is .35 ohms too. The secondary is rated at 7.5k ohms which is close to the factory rating although I couldn't find further information.

The "gain" you may notice isn't really a gain at all. As with all high voltage electronics breakdown begins at the first bolt of electricity. Even normal resistance doesn't mean the coil is in good condition so replacement after higher miles will almost always result in a boost in performance. This doesn't mean you gained anything, you just get back what you deserve.

These are the reasons I don't really feel that spending money on them is necessary, especially if you're on a short budget. I got them becasue at 109k miles it was surely time for a replacement. edit: and obviously I have the DIS-4 system to take advantage of the 45,000v and multiple spark.

Like I said though, I'm still learning so don't take this for anything more than the information is worth.

Good points, Jason. You're right, the difference won't be great. Some people can feel 5hp, some can't. Because the ratio between the primaries and secondaries on the MSD coil are SLIGHTLY farther apart than stock there is a LITTLE to be gained.

I spoke personally with MSD and GM (dealer and corporate) trying to find out the differences between the 'normal' OEM coil, the 97 SSEi coil, and the MSD 8224 to come to my conclusions. GM won't (or can't) tell us what the wind ratio is on the coils, but we do have the opportunity to do some more fine measureing. Using a Megger might be the best way to really see what these coils do.

I have MSD and Pre-97 SSEi coils. Anyone willing to send me a coil from 97+ for temporary loan?

Well you don't need GM to figure that out. Output voltage is a direct result of windings and input voltage. We know the output on both is 40,000v and MSD admits a 80:1 turns ratio and since input voltage doesn't change they both have to be the same.

I think it'd be really neat to see how each performs side by side though.

You can also port the front exhaust manifold for a cheap increase in power. Can also Jet-Hot coat the crossover pipe, and while you are at it could coat the front and rear manifolds if you wanted. Well the front would be easier to take off and the crossover as well. If you wanted to be cool, could get an extra set of 3.8L heads, have them ported and polished, do a quick 3 angle valvejob get some more power of it that way. That would be a fun way and would not cost too much if you did the labor. Like $100-200 bucks for extra pair of heads, like $100 bucks for machine work and like $50 for the new valves. Try to make sure you get heads off a lower mileage motor so they are not warped and the valve guide seals dont have to be replaced. Oh and why didnt I remember this, you could also do the Intense or ZZP higher ratio rockers. That'* another one. Just ideas......

I share the excitement you guys do about performance. I don't take my car to the track or get too crazy on the road. I like to "get on " her sometimes. The only mod I've made to my 1999 se is a rice pipe . I'm wanting to put a Flow Master on it next. I was hoping a PCM or chip could be next and I'd be done. Would this be a wise route to follow?