found the limit of my 408 :(
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From: the not so stock tribe
found the limit of my 408 :( well i guess after years of abuse as a forced induction motor , and then putting it in my stang with a direct port to keep its company , my 408 kinda met its match 
the car ran a best of 9.3@145 during the last race ( 2 months ago) , please remeber that this is a low compression- 8.5:1 motor,no rear brakes or trans brake, and running pump gas ( i use a mix of C16 and premium in the N2O fuel cell) and i drive it everywhere.
well after the last run the car ran warm but nothing else seemed wrong. ( it had the the exhaust system off so i couldn't hear anything )
so i start it today after bolting up the exhaust and i hear a knocking noise, it wasn't lifters ( cause i drove it around and nailed it a few times) , and the car idled real smooth ( remeber this) . it seemed to be coming from the center of the engine. another thing i found out is that the car was down about 3 gallons of water !
so i take the valve covers off to check and everything seemed fine. so i then pulled the plugs ......
i leave you with the pics :
1-3-5-7
8-6-4-2
no.8 had aluminum specs on it , guess where they came from ?!!
these are the plugs (tr8)after hitting them with a 400 shot . i'm thinking that the car lost coolant somewhere , most likely to the sides of the block and into the chambers , and it started running warm , which in turn caused it to knock like hell and maybe run lean. my hunch is that the knocking noise is a bent rod or possibly a broken wrist pin .
i'll be ripping the engine appart tomorow and will tell you what i find .
sad part is i was just about to start converting it back to a blower motor
the car ran a best of 9.3@145 during the last race ( 2 months ago) , please remeber that this is a low compression- 8.5:1 motor,no rear brakes or trans brake, and running pump gas ( i use a mix of C16 and premium in the N2O fuel cell) and i drive it everywhere.
well after the last run the car ran warm but nothing else seemed wrong. ( it had the the exhaust system off so i couldn't hear anything )
so i start it today after bolting up the exhaust and i hear a knocking noise, it wasn't lifters ( cause i drove it around and nailed it a few times) , and the car idled real smooth ( remeber this) . it seemed to be coming from the center of the engine. another thing i found out is that the car was down about 3 gallons of water !
so i take the valve covers off to check and everything seemed fine. so i then pulled the plugs ......
i leave you with the pics :
1-3-5-7
8-6-4-2
no.8 had aluminum specs on it , guess where they came from ?!!
these are the plugs (tr8)after hitting them with a 400 shot . i'm thinking that the car lost coolant somewhere , most likely to the sides of the block and into the chambers , and it started running warm , which in turn caused it to knock like hell and maybe run lean. my hunch is that the knocking noise is a bent rod or possibly a broken wrist pin .
i'll be ripping the engine appart tomorow and will tell you what i find .
sad part is i was just about to start converting it back to a blower motor
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Damn that sucks man, but I think you should have been running a couple stages colder plug. Like in the 10 range. A 400 shot is a lot to ask out of an 8 if you ask me. Especially when you're not running 100 percent race fuel.
But like you said, good excuse to upgrade!!
But like you said, good excuse to upgrade!!
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From: the not so stock tribe
todd, , i am absolutly surprised how smooth this thing ran and idled with those plugs. so far the motor looks fine ( relatively ) . i took the heads off and everything seems ok , no.1 chamber has a few "freckels" from the porceline tip that got knocked off, and some of the walls have a few minor scratches in them, but nothing too bad. will have to hold on the boat anchor plan for now 
termin8tr and ATV, the car ran fine before with those plugs and that shot, timing was set to something in the range of 18 or 19 deg. and thats on 8.5:1 compression
my theory is that the car ran too hot back then , cause we had to put close to 3 gallons of water in it, which inturn caused detonation and melting of the plugs.
venom, the car had 9.0 in it if it only could stall higher ( no rear brakes) and shift properly ( when i wanted it to ), and that is without the second 150 shot stage ( which, thank god, did not work ) . plans,,,,, slap it back together with whatever parts i have here and put the F1-R on it ! i'm tired of refilling bottles
noyzee , sorry can't send them to you ; those puppies are going on the " yup,,, i did that " shelf
i should have the motor out tomorow ( i have everything off the engine: heads-p/s- water pump- tranny bolts etc.), i was just too lazy today to wear my overalls and go under the car to unbolt the torque converter
will keep you posted .
termin8tr and ATV, the car ran fine before with those plugs and that shot, timing was set to something in the range of 18 or 19 deg. and thats on 8.5:1 compression
my theory is that the car ran too hot back then , cause we had to put close to 3 gallons of water in it, which inturn caused detonation and melting of the plugs.
venom, the car had 9.0 in it if it only could stall higher ( no rear brakes) and shift properly ( when i wanted it to ), and that is without the second 150 shot stage ( which, thank god, did not work
) . plans,,,,, slap it back together with whatever parts i have here and put the F1-R on it ! i'm tired of refilling bottles noyzee , sorry can't send them to you ; those puppies are going on the " yup,,, i did that " shelf
i should have the motor out tomorow ( i have everything off the engine: heads-p/s- water pump- tranny bolts etc.), i was just too lazy today to wear my overalls and go under the car to unbolt the torque converter
will keep you posted .
You had to add 3 gallons because you hammered the pistons, plugs and had a head gasket issue that pressurized your coolant system.
Detonation caused by to much timing and to hot of a plug.
On a 400 shot you should be running the coldest plugs you can get.
18* HOLY **** !!! my motor is only 10.5:1 and just because yours is 8.5 doesnt mean you should be running 10 more * of timing. If my motor was 12.5:1 I might take out another degree or two.
If it were my car I would be on strait C16 no mixing, NGK 11 plugs, and around 8-10* of timing. Hope you have better luck when its back up and running.
Detonation caused by to much timing and to hot of a plug.
On a 400 shot you should be running the coldest plugs you can get.
18* HOLY **** !!! my motor is only 10.5:1 and just because yours is 8.5 doesnt mean you should be running 10 more * of timing. If my motor was 12.5:1 I might take out another degree or two.
If it were my car I would be on strait C16 no mixing, NGK 11 plugs, and around 8-10* of timing. Hope you have better luck when its back up and running.
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From: the not so stock tribe
thanks ATV, i was thinking that tr8's would be enough since thats what i had in the camaro when it was making around 1k hp , and as for the timing the plugs looked fine when ever i did run it before , guess i need to learn more
i guess i'll never get to learn more about N2O, cause he plan now is to put the engine back on F/I duty ( at least i think i know what i'm doing there )
here are pics of the heads and pistons:
pass side:
driver side
i guess i'll never get to learn more about N2O, cause he plan now is to put the engine back on F/I duty ( at least i think i know what i'm doing there )
here are pics of the heads and pistons:
pass side:
driver side
Most times you will do less damage when its lean and has to much timing.
To rich and very little timing will tear some **** up !!
Doesnt look to bad, you may want to check the bearings they are probably not in good shape after that beating.
To rich and very little timing will tear some **** up !!
Doesnt look to bad, you may want to check the bearings they are probably not in good shape after that beating.
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From: East Side Performance! mASShole
you suck, just sell me those plugs, i need a good set bad. lol
doesnt look to bad at all.
atv, i hear that, my buddy lifted all the tops on his car with a bit to much fuel. ended up needing $1,000 pistions to replace his new $1,000 pistions. lol
doesnt look to bad at all.
atv, i hear that, my buddy lifted all the tops on his car with a bit to much fuel. ended up needing $1,000 pistions to replace his new $1,000 pistions. lol
Some super tuners seem to think that lifted ring lands mean it was to lean.
The real N20 guys no better.
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From: East Side Performance! mASShole
lifted lands = to much fuel
im some what of a super tunner. lol accually im not even sure how i got my car to run, i still fire up my HP tuners and scratch my head, but hey, i did something right.
id like to have a real good tuner see if they could find more power. id have to say yes.
maybe a dyno tune would work. lol 
The lifted ring lands are fuel firing in between the ring and top of the piston. I learned my lesson, lol. A touch rich is safe, so some people think really rich is good, not! Lean is mean though.