What Plugs for SE Stage 2 Heads?

Discussion in 'Race 400/430/455' started by wormwood, Jan 13, 2008.

  1. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    The reach of the plugs will be the same. The 6 is a hotter plug than the 7. Were the plugs carbon fouled?


    An engine that has a vacuum leak will like a lot of timing to stay running. You may have a vacuum leak inside the valley from the port mismatch. It would have to be pretty significant though. What kind of vacuum is it pulling?
     
  2. wormwood

    wormwood Dare to be different

    well, the engine runs and idles fine at 18 degrees. it just seems to wake up a bit when driving with more timing. vacuum is 9-10 inches at idle dropping to 9-8 in drive. I know that the 6 and 7 ngk plueg are the same legnth, but they DO make extended reach plugs, i didnt get them because i figure that isnt my problem.
     
  3. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member


    Vacuum seems OK for that cam. NGK makes projected nose plugs. I use them in my Stage1SE heads. The FR-5 plug will fit your heads. The gap is positioned deeper into the combustion chamber. That is the way to go, not extended reach. The FR-5 is a little hotter than the plugs you are using. That is as cold as they come.
     
  4. tt455

    tt455 T Bone

    I could be off here Dan,but I'll throw it out there anyway.Is it possible when you put your intake manifold back on you didn't quite seal it properly esspecially by the back? I understand you did the vacuum test,but if you cup your hands over the carb and she dosen't stall,you have a vacuum leak.I'm probably wrong,but just trying to help.Tom.
     
  5. wormwood

    wormwood Dare to be different

    ok, i covered the carb with my hands while it was running and it shut down.
     
  6. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Sure would help to see your timeslip. What was your 60' before and after, trap speed?
     
  7. wormwood

    wormwood Dare to be different

    funny thing is ill never have my timeslip from thre 11.9 run cause i had it out on display at a car show and someone stole it..:Dou:
     
  8. gusszgs

    gusszgs Well-Known Member

    OK, what about the 13.4 slip? Any chance of finding that one?

    Do you happen to recall your approx mph on either times?

    One more......can you provide some details on your fuel system. Electric, mechanical, line size ect...
     
  9. Buicks4Speed

    Buicks4Speed Advanced Member

    How long have you been running this carb? Do a tear down and look for your problem there. If everything else is right, then your not getting enough fuel or too much. Check jetting, air bleeds, power valves, and needle and seats. I have seen a few float bowls corrode up from sitting and may plug the jets or needle & seats. Or you had it over-jetted before and now that is running better, its pulling too much fuel. :Do No:
     
  10. wormwood

    wormwood Dare to be different

    im not positive BUT i believe my mph on the 11.9 run was around 108 and on the 13.4 was around 97? but thats just a guess. my fuel system runs via holley blue electric pump, fuel flows through 1/2 braided steel line. to a regulator near the carb. i DID go to change fuel filters a few weeks ago and discovered a horribly corroded filter, it was rusted to heak and practically fell apart in my hand. so i replaced that with an aluminum tube style one, but i dont think that that was my problem because i didnt find any signs of dirt in the carb so i think it was still filtering.

    rick.. i used the same carb in the 11.9 run that i did in the 13.4 run. i thought that maybe now my car needs more fuel with the port job and bigger cam so i just purchased a pro-form 1050 cfm holley style carb. so far its running like crap, (backfiring out the exhaust) but i think it just needs to be tuned in? i dont know.
     
  11. whamo

    whamo 454 71 skylark custom

    Do you have a fuel pressure gage? Did you check your throttle adjustment to make sure your carb was going to full open on both primarys and secondarys?
     
  12. wormwood

    wormwood Dare to be different

    yes i have a fuel pressure guage. i WAS running at 7 psi, the quick fuel guys said to lower it to 6, and yes i checked to make sure throttle linkage allowed me to go to W.O.T.

    thanks all for these great suggestions guys, keep them coming, all suggestions will be looked into!
     
  13. whamo

    whamo 454 71 skylark custom

    Sorry, not trying to be a wisea$$ about the throttle. I had a car that was running 9.00's and it dropped off to 10.90's. We were dumbfounded, then my best friend looked down the carb throat and said....uhhhh, I think I found the problem........ next pass was 9 flat at 150mph.

    Do you run at PIR?
     
  14. 70aqua_custom

    70aqua_custom Well-Known Member

    :Smarty: after you eliminate all the easy stuff, that 10% of doubt about the cam starts to grow. Is your oil gray looking? The symptoms are consistent with a cam that is eating itself.
     
    Last edited: Feb 6, 2008
  15. Buicks4Speed

    Buicks4Speed Advanced Member

    Doesn't mean it was flowing good with that filter. BUT with it backfiring out the exhaust, you may very well have a valve spring issues and floating the valves since you are getting raw gas in the exhaust and igniting it. You did just change the cam right? how old are the springs? What is there installed closed and open pressure? Either that or it is stupid rich.
     
  16. wormwood

    wormwood Dare to be different

    no, i've been using this cam for awhile now, the backfiring out the exhaust just started with the carb change. swaping out carbs is one of the things i did to remedy the drop in performance. i havent made a run with it yet. it probably needs to be tuned up, and im not that knowledgable with that.

    what do you mean "cam eating itself"? i will check oil color. i use amsoil synthetic, will that matter?
     
  17. 70aqua_custom

    70aqua_custom Well-Known Member

    What this means is some or all of the lobes are wearing at a high rate. The metal that comes off the cam lobes gets into the oil. The tiny particles of metal will turn the oil to a gray color. This wear starts during break in and as the lobes wear, performance gets worse and worse until the engine starts to backfire and eventually it won't run at all. The metal that was pumped throughout the engine will take its toll on the crank and all of the bearings. When this happens, a complete rebuild is needed. This problem is usually caused by a lack of proper lubrication which can be due to improper break-in or improper break-in lubricant. It can also be caused by a bind in the valve train like when the valve train cannot support the lift of the cam. Once in a while a cam isn't heat treated properly and it will go bad.

    The type oil oil you're running after the fact means nothing. Once a cam wears past the heat treating, the high wear rate cannot be stopped.
     
  18. wormwood

    wormwood Dare to be different

    could this happen due to an improper break-in?

    also, do you guys think that its a good idea to take it to the dyno? or take off the heads and flow tese them? or would these be a waste of time and money?
     
  19. tlivingd

    tlivingd BIG BLOCK, THE ANTI PRIUS

    i'd worry about the flat cam lobes as mentioned. you could also check for a flat by measuring the lift by taking the valve covers off and using a dial indicator. each intake valve should be very close to the same lift.

    do you by chance have two plug wires crossed. I've done this for a whole summer when i was using my vert as a daily driver.

    you say you have a blue holley, is that pushing thru the factory mechanical fuel pump? if so are you sure the holley is still pumping, and do you have a good ground at the holley and it's not pulling a ground thru the fuel system.

    my uncle had a daily driver buick back in the day 70's and he had one of the baffles in the muffler break loose and lay against the outlet of the muffler. caused a huge back pressure issue and a loss of performance (but it still ran)
     
  20. whamo

    whamo 454 71 skylark custom

    In my opinion ,flow testing the heads would be a waste of time. The only way I could see the port match hurting your numbers that badly would be if it caused a vaccum leak.

    I would put the 850 back on the engine and see if the popping goes away. Then check for a flat lobe on the cam with a dial indicator. I have one if you need to borrow it. Harbor freight sells cheap ones with a magnetic base that would work. Then I would check that cam timing. I have a degree wheel you could use as well.

    Have you checked to see if the outer ring on your balancer may have slipped? That would throw off your timing marks so that the timing light would be way off. I also have spare balancers. Let me know if I can help.

    Any metal contamination in the oil???? Are you running through mufflers? What kind of ignition system are you using? How far apart was the engine when you did the recent work?
     

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