Trick Flow 240's and Spark Plugs

[hunt2elk]

What heat range plugs are you guys using on your TF's? Reason I ask is I am getting some detonation on a newly rebuilt 499 stroker. It came back to me with base timing at 17 and total at 35. MSD ready to run distributor with 2 blue medium springs bringing total timing in at 2350 rpm. I put in the 2 heavy silver springs which holds off the total till 4000 rpm. Now if I back the timing down to 30 it is pretty good. But I want to jack the total back to at least 33. The engine builder has NGK BKR6E-11 pugs in it and I ran across an article stating that dropping down a heat range will help. My other cars with Stealth heads are using BKR5E plugs and am wondering if I should try them?

 

[68 HEMI GTS]

How much compression? You could go to a 7, that’s colder than 6. A 5 is a hotter plug.

 

[hunt2elk]

How much compression? You could go to a 7, that’s colder than 6. A 5 is a hotter plug.

See how much I know about this stuff? He told me the compression is 10:1. I told him it had to run on 91 octane 100% gasoline as that is the best we have here.

 

[68 HEMI GTS]

I’m surprised the 6’s are too hot. Can you snap a pic of one to see how it looks?

 

[hunt2elk]

I’m surprised the 6’s are too hot. Can you snap a pic of one to see how it looks?

#1 plug. At idle and cruise it is running rich, and wot slightly lean according to my AF gauge. I need to get the timing back up before messing with the carb though. There is only 150 miles on these plugs. I do have a new set of the same ones. Maybe I should change them out?

 

[68 HEMI GTS]

Honestly they don’t look that bad. I’m wondering if maybe you got some **** gas. You don’t want to keep rattling it. I run 6’s in my 10.5 511 on pump premium with no issues. I tried 7’s once but they were a bit cold for my combo. I would put a set of 7’s in it for now but then I’d try to get rid of that gas and try some different stuff.

Is there anyplace you can pick up 5 gallons of race gas to toss in it to get through this tank?

 

[hunt2elk]

Honestly they don’t look that bad. I’m wondering if maybe you got some **** gas. You don’t want to keep rattling it. I run 6’s in my 10.5 511 on pump premium with no issues. I tried 7’s once but they were a bit cold for my combo. I would put a set of 7’s in it for now but then I’d try to get rid of that gas and try some different stuff.

Is there anyplace you can pick up 5 gallons of race gas to toss in it to get through this tank?

Are you able to run it at 35 degrees of timing? It is only detonating when I floor it, so I can just drive mellow till I burn up whats in the tank.

 

[68 HEMI GTS]

Yes, I keep mine totaled around 35-36 range. What’s your WOT A/F?

 

[hunt2elk]

Yes, I keep mine totaled around 35-36 range. What’s your WOT A/F?

13

 

[68 HEMI GTS]

13

ok, I found mine to run best, make most power at low 12’s on pump fuel.

 

[hunt2elk]

ok, I found mine to run best, make most power at low 12’s on pump fuel.

That is what I will get it to, but need to get the timing advanced first.

 

[PRHeads]

Cam specs?
Cranking compression?
Engine temp?

Sounds like it might be a good candidate for some sort of vacuum advance.

 

[hunt2elk]

Cam specs?
Cranking compression?
Engine temp?

Sounds like it might be a good candidate for some sort of vacuum advance.

Cam card and a list of what's in the motor. It runs at a steady 190 degrees. I don't know what the cranking compression is.

 

[beanhead]

If Hafliger built and dyno'd it...I'm surprised it's detonating. Have you reached out to Brian? They had to be testing it with our 'awesome' CA gas. Did they have your carb?
Just for comparison, I use a 5-range ngk at 9.5 compression, (160 avg cranking with the comp 275HL, two steps smaller than your cam)190-degree .060 over 440 with .100 piston to head distance, hot weather, CA 91, never pings..6s were a tad cold.
Anything can happen, but just to throw this out there- you're positive it's detonation you're hearing and not something else, like an accessory, bearing, fan scraping?....Bad motor mount can cause all kinds of weird noises, only under power, that sound like detonation. (**just sayin'....because I just went through this!!**)
The 'all in' at 2300 may have been a tad quick, depending on your weight/gearing/converter, maybe?
Bad gas--definitely could cause trouble, especially if it just started happening out of nowhere. After having to put a few emergency gallons in at a cheap-o station once, my '04 hemi Ram started knocking so bad sitting in a drive-thru I though the engine was gonna fall out. Once I got decent stuff back into it, never experienced that since. (Looks like a sweet build BTW, from that spec sheet- nice!)

 

[hunt2elk]

If Hafliger built and dyno'd it...I'm surprised it's detonating. Have you reached out to Brian? They had to be testing it with our 'awesome' CA gas. Did they have your carb?
Just for comparison, I use a 5-range ngk at 9.5 compression, 190-degree .060 over 440 with .100 piston to head distance, hot weather, CA 91, never pings..6s were a tad cold.
Anything can happen, but just to throw this out there- you're positive it's detonation you're hearing and not something else, like an accessory, bearing, fan scraping?....Bad motor mount can cause all kinds of weird noises, only under power, that sound like detonation. (**just sayin'....because I just went through this!!**)
The 'all in' at 2300 may have been a tad quick, depending on your weight/gearing/converter, maybe?
Bad gas--definitely could cause trouble, especially if it just started happening out of nowhere. After having to put a few emergency gallons in at a cheap-o station once, my '04 hemi Ram started knocking so bad sitting in a drive-thru one time I though the engine was gonna fall out. Once I git decent stuff back into it, never experienced that since.

I am positive it is detonation. Yes, Brian built it and dyno'd it. The whole package came from him including the carb and distributor. As soon as I threw a timing light on it and saw how fast the advance was coming in, I new that was a problem. I did call him at that point because he forgot to send the MSD bushings and springs to me. He told me to drop the timing to 33 and put in the heavy springs, which I did. He thought it was a lack of fuel problem. I am running a Carter 9603 mechanical pump and he thought it was going lean when I got into the gas pedal. Now that I have my A/F meter in the car, I know that is not the problem.
I am really hoping it is bad gas, but I have gotten some from 2 different stations with no change. I would think by now all the winter gas should be used up?
Another thing, how are you guys determining when a plug is to cold?

 

[PRHeads]

Inquiring minds want to know.......

What did the power numbers look like?

I’d do a warm cranking compression test on a couple cylinders where the plugs are easy to reach.

 

[hunt2elk]

Inquiring minds want to know.......

What did the power numbers look like?

I’d do a warm cranking compression test on a couple cylinders where the plugs are easy to reach.

Dyno sheet. I see Brian wrote down that it is 9.9:1 compression ratio.

 

[beanhead]

I am positive it is detonation. Yes, Brian built it and dyno'd it. The whole package came from him including the carb and distributor. As soon as I threw a timing light on it and saw how fast the advance was coming in, I new that was a problem. I did call him at that point because he forgot to send the MSD bushings and springs to me. He told me to drop the timing to 33 and put in the heavy springs, which I did. He thought it was a lack of fuel problem. I am running a Carter 9603 mechanical pump and he thought it was going lean when I got into the gas pedal. Now that I have my A/F meter in the car, I know that is not the problem.
I am really hoping it is bad gas, but I have gotten some from 2 different stations with no change. I would think by now all the winter gas should be used up?
Another thing, how are you guys determining when a plug is to cold?

Okay thanks. As far as the plugs, You'd like the first 2 or 3 at most(on an ngk) threads be colored up. It's hard for me to tell from your pics, but in the top left one, it looks like the first two threads are colored? That's fine, at least really close. Tough for me to see on my old screen. But too cold would be, if there was heat coloring on only the first thread. If it was too hot you'd have that nice toasty brown sugar down to the fourth and beyond. Either way, it doesn't appear, to my eyes here at least, that your heat range is too far off. Especially not toward the 'too hot' direction. Now, I'm just a nobody but what I would do is cut the threads off a plug and examine the very bottom of the porcelain for your WOT ring. I would NOT be completely relying on the gauge...yet. If you have a nice little brown ring down there, around .100" in width, you're WOT mix is in the ballpark and your meter reading is okay. If it's a very small, very light-colored ring or too clean? You're running leaner than you want and the gauge is fibbing...13 may not be max power, but it shouldn't be so lean it rattles? These other guys will know far more than me on that....
You'll also be able to better see how much, if any, 'speckling' is in there---hopefully none! That would be piston material..

 

[beanhead]

Dyno sheet. I see Brian wrote down that it is 9.9:1 compression ratio.

View attachment 952008

 

[hunt2elk]

View attachment 952012

Should be good stuff, but it sure doesn't feel like a 600 hp motor to me. Brian built me a 408 for my Duster a couple years ago and that flat out rocks. That car would walk all over this one. And that motor only has 470 or so hp.