The best T.P.I spark plug
The best T.P.I spark plug
Whats the best Plug for a 85 IROC that fairly stock exept that Accel HEI coil, 8mm wires. Cylnder 2 was bad oil rings and keeps fowlin that plug. I got those BOSH platnum 4s in right now But I dont really like them cuz before I went platnum I never got fowled plugs "not a one delco ever let me down like that BOSH in cylnder 2. I was thinkin split fire what do you think.
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Joined: Oct 2005
Posts: 245
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From: Troy, Ohio
Car: 1987 Trans Am
Engine: 383
Transmission: TH400
Axle/Gears: 9 bolt 4.11
Originally Posted by SplitFire-Z
Whats the best Plug for a 85 IROC that fairly stock exept that Accel HEI coil, 8mm wires. Cylnder 2 was bad oil rings and keeps fowlin that plug. I got those BOSH platnum 4s in right now But I dont really like them cuz before I went platnum I never got fowled plugs "not a one delco ever let me down like that BOSH in cylnder 2. I was thinkin split fire what do you think.
I got Accel U groove shorties and they have been thru all kinds of conditions.....still run strong with them...
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Joined: Aug 2005
Posts: 3,004
Likes: 4
From: Yellowknife, NWT, Canada
Car: 84 Z28
Engine: 357
Transmission: TH-350C
Axle/Gears: 3.43
Dont worry about getting a fancy preciuos metal plug with 2/4 electrodes. Their not worth it!
Now if you did something like ol'blue and got the Shorty's those will help you alot during the next plug change. These things arent very fun to do and can take quite some time untill you get the hang of it.
Now if you did something like ol'blue and got the Shorty's those will help you alot during the next plug change. These things arent very fun to do and can take quite some time untill you get the hang of it.
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Joined: Jun 2003
Posts: 1,386
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From: Toronto CANADA - GM Parts Rep.
Car: 1987 Iroc Z28
Engine: The KING of the 3rd gen TPI's.
Transmission: Beefed up T5
Axle/Gears: Aussie 3.45's
I try to use AC Delco as often as possible, including plugs. They come in standard, rapidfire, and platinums.
GM Performance parts aswell.
GM Performance parts aswell.
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Joined: Jun 2006
Posts: 249
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From: Colorado
Car: 1986 Trans Am/1993 Trans Am
Engine: 305 .030 over built/ LT1 Bolt Ons
Transmission: t5/700r4
Axle/Gears: 3.43 Posi/3.23 Posi
I like Ac Delco rapid fire plugs over regular Ac Delco ones. They seemed to just run better and helped me with performance so....
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From: Cincinatti OH
Car: 1991 L03 700r4 RS
Engine: 1987 WS6 Trans AM Lb2
Transmission: Th350 red neck Performance 3k stall
Axle/Gears: 95 Mustang 8.8 built with 3.73s
I nor any of my friends have ever been let down by a set of Bosch Super's. They're short enough to clear headers, cheap enough to change often, and I've seen them run fine in turbo, nitrous, and NA applications.
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Joined: Jun 2006
Posts: 249
Likes: 0
From: Colorado
Car: 1986 Trans Am/1993 Trans Am
Engine: 305 .030 over built/ LT1 Bolt Ons
Transmission: t5/700r4
Axle/Gears: 3.43 Posi/3.23 Posi
Not sayin bosch sucks, but there are better and you asked whats the best tpi plug.
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Joined: Jun 2006
Posts: 408
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From: NJ
Car: 87 IROC
Engine: 5.7 TPI
Transmission: 700-R4
Axle/Gears: BW 7.75" 3.27
I've had bad luck with Bosch. I gave them plenty of chances and I'm sick of them. AC's are the way to go. This time when I switch the Bosch's out, AC's are going in.
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From: Baltimore, MD
Car: 09 Cobalt SS Sedan. 92 Z28 vert
Engine: 2.0T EFR6758; 5.0TT T3/T4 8psi
Transmission: F40; 700r4
Axle/Gears: 3.76 LSD; 3.23 posi
I have no complaints on my bosch platinums in my car (see sig)
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Joined: Sep 2004
Posts: 878
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Car: 89' Iroc-Z G92
Engine: TPI 305 G92
Transmission: T-5
Axle/Gears: Limited 9 bolt, 3.45
Bosch Single Platinums- They lasted a whole 12 miles.
Bosch Platinums +4 - What I am currently running.. They are starting to build up carbon @ 500-700 miles. I have blown two in the number two cylinder due to a bad fuel mixture in that cylinder. My engine is currently running a 15* base advance(wot) and 45* total. Gasoline usually is 93 octane and occasionally gets extra alcohol.
I am not looking forward to oxidated fuel. As I have not filled up my tank with this stuff yet. The newer fuel from the past two years lite my cats on fire @ high rpm due to higher degree of alcohol and MTBE than the cats were designed for...
AC/Delco's lasted the car up until 1996 @ 26k miles, I have no complaint with them.. As long as you aren't running crazy ignition timing, stay with them.. TPI305, 37,000 miles.
Bosch Platinums +4 - What I am currently running.. They are starting to build up carbon @ 500-700 miles. I have blown two in the number two cylinder due to a bad fuel mixture in that cylinder. My engine is currently running a 15* base advance(wot) and 45* total. Gasoline usually is 93 octane and occasionally gets extra alcohol.
I am not looking forward to oxidated fuel. As I have not filled up my tank with this stuff yet. The newer fuel from the past two years lite my cats on fire @ high rpm due to higher degree of alcohol and MTBE than the cats were designed for...
AC/Delco's lasted the car up until 1996 @ 26k miles, I have no complaint with them.. As long as you aren't running crazy ignition timing, stay with them.. TPI305, 37,000 miles.
Last edited by Mcdamit; Jun 29, 2006 at 11:08 PM.
Joined: Jun 2001
Posts: 8,028
Likes: 93
From: DC Metro Area
Car: 87TA 87Form 71Mach1 93FleetWB 04Cum
There is no way, NO WAY that you killed a set of any plugs in 12 miles, even if they were totally the wrong plug, unless you've got something really, REALLY screwed up with your car.
And again, MTBE and ethanol will both cause your cats to run cooler unless there is something really screwed up with your car.
And again, MTBE and ethanol will both cause your cats to run cooler unless there is something really screwed up with your car.
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Joined: Oct 2005
Posts: 245
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From: Troy, Ohio
Car: 1987 Trans Am
Engine: 383
Transmission: TH400
Axle/Gears: 9 bolt 4.11
Personally I stay away from AC Delco's.....of course I was running a ford when I tried them. My old 1987 turbo mustang would really eat them in a day....they would foul out really easily.....believe it or not the plugs I had luck with were Autolites.....But like I said that was a ford and it liked to bounce between rich or lean every other day for some odd reason.
I was going to say Autolites as well.
In your case, plain old Autolite 24s. They have the right thread length and tapered seat design to work with your heads. They also have a projected nose and a slightly larger gap (.045") that will work well with your mildly enhanced ignition. Plus, they are a semi-shorty design that clears most headers. I've used them a zillion times in stock GM heads without ever a failure that is a result of the plug itself. They are my go-to plugs for most stock cast iron small block heads.
In your case, plain old Autolite 24s. They have the right thread length and tapered seat design to work with your heads. They also have a projected nose and a slightly larger gap (.045") that will work well with your mildly enhanced ignition. Plus, they are a semi-shorty design that clears most headers. I've used them a zillion times in stock GM heads without ever a failure that is a result of the plug itself. They are my go-to plugs for most stock cast iron small block heads.
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About forty minutes to an hour. 
