How do I know what heat range plugs to run (non-f-body)
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From: Hayward, CA
Car: 91 camaro
Engine: 383
Transmission: T56
How do I know what heat range plugs to run (non-f-body)
This is for my truck. The engine was originally from a 76 impala. Now it's got headers, Edelbrock Performer intake, and 650 carb. I was gonna run an R45TS (delco)which is what is recommended for the impala, but a guy I know said they're too hot, that I should get 43s. Is he right? How am I supposed to know? I also changed the compression ratio to about 10:1 when I rebuilt it. It still has the old cast heads, 882s. Suggestions, please!
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91 Z28
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91 Z28
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From: Mesa, AZ
Well our cars run the R45TS for stock plugs and run a 9.3:1 stock compression ratio. And you want to go with a colder plug the higher the compression ratio gets. I think the 45's would be fine, but I think the 43's would work too. I would go with the 45's since that is what is recommended for the Impala and you also want the hotter spark plug to get the most performance and power. Just as long as its not too hot and doesn't cause detonation.
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Senior Member
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Joined: Nov 1999
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From: Hayward, CA
Car: 91 camaro
Engine: 383
Transmission: T56
The original compression ratio on the engine was really low, like 8:1 or something like that, can't quite remember. But I could run a 44. I'm not having a problem with detonation at all but the 45s I was using are all fouled out. But thats definitely due to bad timing and running too rich/lean.
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91 Z28
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91 Z28
Come see The Vicious...
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Joined: Jan 2001
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From: Mesa, AZ
You could run a 44 or just try to get your timing and a/f ratio mixture right with running the 45's and then check the spark plugs and make sure that they aren't fouling. But once they are fouled I'm pretty sure they are just bad.
This has some really good info if your interested in reading...
http://www.ngksparkplugs.com/techinf...s/overview.asp
This has some really good info if your interested in reading...
http://www.ngksparkplugs.com/techinf...s/overview.asp
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Joined: Sep 2001
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From: Ontario, Canada
Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
Transmission: TH-350/3500stall
Axle/Gears: 7.5" Auburn 4.10 Posi-Traction
Picking a plug heat range is always a compromize on a street motor. Generaly
the stock "lowPerf" heat range is good for everyday driving. But if your going to flog
it a lot then you should run a little cooler plug. I've had good results with AC R42T or(TS)
and Champion RV8c. This is the stock plug for the 1970 LT-1 and LS-6 Corvette motors.
It's about 3 to 4 heat ranges cooler than R45TS. Seems to work good on Hi perf 10:1cr street/marine motors and mild Blowers and Nitrous.
Forget about Platitium plugs for racing. One of the ways they make them last so long in stock applications is to make them run hotter.
the stock "lowPerf" heat range is good for everyday driving. But if your going to flog
it a lot then you should run a little cooler plug. I've had good results with AC R42T or(TS)
and Champion RV8c. This is the stock plug for the 1970 LT-1 and LS-6 Corvette motors.
It's about 3 to 4 heat ranges cooler than R45TS. Seems to work good on Hi perf 10:1cr street/marine motors and mild Blowers and Nitrous.
Forget about Platitium plugs for racing. One of the ways they make them last so long in stock applications is to make them run hotter.
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