Pulled heads on the 408. Engine/head status pics inside.
Thread Starter
Joined: Jun 2004
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From: Alexandria, VA
Just finished pulling the heads to send them off to get ported. The engine will finally have some decent heads that will hopefully allow it to come to life a little bit more. I just included a few pics of the pistons and heads to show the status of the internals after about 1800 miles. Can you tell it's running a bit rich
AFR was between 12.1 and 12.9 on the dyno when it made 425/445. Spark plugs look pretty good, but was debating moving back to TR55's instead of the TR6's since this thing never sees juice. Any thoughts on that? Hopefully the new heads can put some more lead in this thing's pencil. Random comments welcome.
AFR was between 12.1 and 12.9 on the dyno when it made 425/445. Spark plugs look pretty good, but was debating moving back to TR55's instead of the TR6's since this thing never sees juice. Any thoughts on that? Hopefully the new heads can put some more lead in this thing's pencil. Random comments welcome. Thread Starter
Joined: Jun 2004
Posts: 5,125
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From: Alexandria, VA
Plenty of room and the studs alleviate a lot of the headache of the coolant/crap that would otherwise get trapped in the bolt holes. Of course I'm gonna remove mine anyway just to make completely sure they are clean because a few studs came loose when removing the nuts, but on the average you don't have to. I would stick with the 6's as well.
If you got 1800 miles with them w/o problems and are staying with the same compression or higher then the TR6's should be great.
Why fix something that isn't broken?
If you got 1800 miles with them w/o problems and are staying with the same compression or higher then the TR6's should be great.
Why fix something that isn't broken?
Thread Starter
Joined: Jun 2004
Posts: 5,125
Likes: 4
From: Alexandria, VA
Originally Posted by JZ'sTA
I would stick with the 6's as well.
If you got 1800 miles with them w/o problems and are staying with the same compression or higher then the TR6's should be great.
Why fix something that isn't broken?
If you got 1800 miles with them w/o problems and are staying with the same compression or higher then the TR6's should be great.
Why fix something that isn't broken?
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Nothing looks out of sorts to me. Looks like more of an oil burning issue than running too rich. Im running 10.9 compression on TR6's gapped at .045 with good results. Id keep the TR6s.
Thread Starter
Joined: Jun 2004
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From: Alexandria, VA
Originally Posted by GuitsBoy
Nothing looks out of sorts to me. Looks like more of an oil burning issue than running too rich. Im running 10.9 compression on TR6's gapped at .045 with good results. Id keep the TR6s.
It looks like caked up burnt oil in your combustion chambers. Not that mine looked any better, but thats why i went to breathers and then to a modified PCV setup.
And those plugs dont look too bad from here.
And those plugs dont look too bad from here.
Might want to try a catch can or a oil/air seperator used for air compressors. As for cleaning it up, I use laquer thinner or acetone and a plastic sponge. Works great at removing head gasket remnants as well.
Originally Posted by ArcticZ28
I will be staying 11.1 and would only go higher in the future, still debating on whether or not to have the heads milled and if the cost/benefit ratio would be worth my while (looking for people to chime in on that one as well). I was just concerned that the TR6's were leaving some HP on the table being that they're geared toward higher hp/juiced engines with the increased gap.
quench(squish).
Thread Starter
Joined: Jun 2004
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From: Alexandria, VA
Well, I've been talking to Jake Fusion and have been contemplating a different route. Considering the extremely low DCR with my cam (7.4:1), Jake suggested milling the heads .018 and running a cometic .040 gasket to give me a .032 quench. This would bump up my SCR to about 11.8:1 and give me a DCR of 8.2:1 which would help gain back a lot of the lost power with my low DCR.
Originally Posted by ArcticZ28
Quick question, do the plugs look like they should be replaced? They don't look bad at all but was debating whether or not to get a new set.
only makes sense to me. why put used plugs?
Kinda on topic...kinda off topic.
11:1 402ci....TR55's made 526 RWHP N/A. Should I stay with what works? Or go to TR6's for a touch cooler plug?
Motor looks good BTW Arctic. Are you running the stock PCV?? Catch can??
11:1 402ci....TR55's made 526 RWHP N/A. Should I stay with what works? Or go to TR6's for a touch cooler plug?
Motor looks good BTW Arctic. Are you running the stock PCV?? Catch can??








