Exhaust/MSD ignition coils; to do or not to do?

**Blacknight02GT** · 10-01-2009

I've got an 02 GT that i've had for the last few years.. and every so often I add a new mod. I get bored if i'm not always doing something, but yet i don't have alot of time or the know how to attempt a successful top swap. All i have now is a CAI and will definitely be getting the PCM tuned either by overkill or Intense over the winter. Now, I was looking online at the Grand Prix store and was thinking about the SLP catback exhaust and MSD ignition coils. Should i do a U bend delete (find somebody with a welder) and get the catback; or should i just get the high flow cat converter they have with the U bend delete already taken care of and not worry about the cat back? What will give me better performance out of a N/A car? Also are the MSD's any good? Thanks.

**TheOtherNick** · 10-01-2009

coils are just for looks. The down pipe would be your best bet.

**Liquifire** · 10-01-2009

^^^^as stated above by 01 GTP....he speaketh the truth. The MSD coils are actually rated lower than stock as I have read. Get a downpipe with or without cat, and this includes the u bend delete in it.

**BwolfGT** · 10-02-2009

I've heard the MSD coils are actually worse than stock, so no on that. The GTP coil packs would be a minor upgrade but other than that just leave it alone, unless you're pushing like 400 whp ignition mods really don't make any noticeable difference. I've heard the SLP catback sounds sick, but that's about all it does, there's no performance gain from a catback. If I were you I'd get a 2.5" catted Downpipe for the exhaust which will show some good performance gain, and that will also get rid of your U-bend and include a high-flow cat like you were thinking of getting. Then if you want it to sound good pick up that catback system.

**Uno99** · 10-02-2009

Please dont get the coil packs. Mine went bad as well as 2 other local GP guys in my area. My stockers are back on my ride now.

Get the u-bend outta there. Like others have said get a DP. The stock cat-back flow pretty good IMO. I say get a 2.5 or 3" DP fo sho.

**Liquifire** · 10-02-2009

as stated above, the stock cat back flows good until 350 WHP, so there will be no performance improvements for that mod. Forget the catbacks unless you are doing it for sound. If you want it just to sound good, save some money and just order some borla mufflers to put on it. That will improve sound and save you money. Personally, I would go with the 3" DP and that will give you a little bit of a deeper tone as well, along with performance gains....

**BwolfGT** · 10-02-2009

Originally Posted by Liquifire

as stated above, the stock cat back flows good until 350 WHP, so there will be no performance improvements for that mod. Forget the catbacks unless you are doing it for sound. If you want it just to sound good, save some money and just order some borla mufflers to put on it. That will improve sound and save you money. Personally, I would go with the 3" DP and that will give you a little bit of a deeper tone as well, along with performance gains....

I'd go 2.5 on a lightly modded GT, but everyones got their own opinion on that bI guess.

**Liquifire** · 10-02-2009

are there any plans for an HV3 or to mod beyond the downpipe ever? If so, get the 3" IMO.......if you stop with the DP and aren't going to touch it, toss up...depends on preference as the 2.5 is barely bigger than stock, and pretty much just deletes the u bend. Kind of a waste IMO. If you want a deeper tone, or to flow better on higher rpms's get the 3" IMO...

**Blacknight02GT** · 10-03-2009

Originally Posted by Liquifire

are there any plans for an HV3 or to mod beyond the downpipe ever? If so, get the 3" IMO.......if you stop with the DP and aren't going to touch it, toss up...depends on preference as the 2.5 is barely bigger than stock, and pretty much just deletes the u bend. Kind of a waste IMO. If you want a deeper tone, or to flow better on higher rpms's get the 3" IMO...

Alright, thanks for all the great advice. No, I don't really have any other plans or an HV3 planned for the future, but it looks like I should still get the 3" downpipe anyway huh? Where do I buy this thing from anyway?

**Blacknight02GT** · 10-04-2009

Originally Posted by Liquifire

^^^^as stated above by 01 GTP....he speaketh the truth. The MSD coils are actually rated lower than stock as I have read. Get a downpipe with or without cat, and this includes the u bend delete in it.

Okay, looks like I will be avoiding the Coil packs thanks for the heads up on that one. Where do I get a downpipe from that includes the u bend delete?

**ZR1Vette09** · 10-04-2009

ZZP has it ZZ Performance

**Liquifire** · 10-04-2009

yes, get it from zzp. They have the best pricing on downpipes by far, and have a very good quality part here whether you go catless, stainless, or aluminized.

**Uno99** · 10-04-2009

How much cash do you have to work with?

**99prixgt** · 10-04-2009

3" d/p on an N/A car is just silly, get a 2.5". Fwiw, im still running stock gt coil packs

**minichopper6hp** · 10-04-2009

There is no difference in gt/gtp coil packs.

**Blacknight02GT** · 10-04-2009

Originally Posted by Uno99

How much cash do you have to work with?

I'll check out zzp then for sure. Ah, well i'd like to not spend over 400 on this endeavor but it doesn't really matter I have enough money free for anything not ridiculously overpriced.