To save you some time, the part#'s aren't tr7 and 8. They are...R5671A-7 and R5671A-8 these are the equivalent of TR-7 and TR-8. The only diff is, these are non resistor and they don't have a projected tip like the TR-6.

 

Did you have the heads checked for warpage?I know that your engine had already been apart from your previous posts and the heads might need to be trued.A small amount of warpage could have kept your Cometics from sealing and caused the blown head gasket you have now.

 

Just found the resistor type colder than tr6. Its part# is BR7EF

 

I told Jim to Oring those heads before he reassembled that motor last month. He said he didn't want to spend any more money than necessary on that motor so the savings could go towards a built motor.

Notice how clean those pistons are. Were they that clean before you reassembled the motor or is that due to the steam cleaning they got when the head lifted?

 

I was under the impression nitrous helped clean pistons and such also...

I didn't look at the pics as dialup is sooooooo slow here. Are both heads pulled or just one? If both, do all 8 pistons look the same...were both head gaskets popped?

 

The plug part #'s I gave are all for non projected tip-plugs. The TR-6 is a projected tip plug. When you run a non projected tip, it lowers comp ratio very slightly. This would probably be a good thing for you.

 

wow, lots of posts.

first let me say it again for nosjohn, i am only spraying for 1sec at the most, just to get it moving. i could be wrong but i dont think the nitrous is the problem, when the nitrous shuts off i am at about 50lb/min of air and that is at least 10lb less than my peak.

i had the heads trued up last time it was apart, stock pistons.

i plan on building a killer 409 eventualy so i dont want to spend any more money on this motor. if i am at the limit of this set up then thats what i would like to know but if i had a tuning or asembly problem then i will fix it and push it harder

 

both head gaskets have signs of problems

 

True the heads,put it back togather and drive it until you build the 409.It's plenty fast to play with on the street with 11 or 12lbs. of boost and you can save your money and efforts to build a all forged 409.

 

Supposedly, when reading your plugs, if the plating is burned past the bend on the top electrode, you need to go colder . Looking at the pics, yours looks burned almost to the threaded part.