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Recent content by PRHeads

  1. PRHeads

    Understanding Cam Specs

    As I said, those three items need to all be looked at together as a “system”. At this point, I’d start with getting the ignition curve sorted out. I think you’re going to want at least 15* of initial timing, idling in gear. More initial timing = more idle vacuum……..and more vacuum helps pull...
  2. PRHeads

    Understanding Cam Specs

    The cam in post #1 has an LSA of 110, with a recommended ICL of 106. I look at it as a Lunati version of a Comp XE268. One thing I’ve found that can affect idle quality is the carbs ability to provide enough idle fuel mixture to the engine with a reduced vacuum signal(lower vacuum). I...
  3. PRHeads

    Help Choosing a Cam/Converter- 9:1(ish) Stock Stroke 400

    I just ran the numbers………Looks like the 9:1 target will be easy enough to reach. With no milling and 88cc heads, and using a .040 gasket, you’ll start out at about 8.3:1. Then you need to lose 9-10cc’s somewhere, which brings it right into the 9:1 range.
  4. PRHeads

    Question About 440 Piston Choices

    Pump gas street build with iron open chamber heads……. The KB184 gets my vote, with the quench area of the heads set/equalized for effective quench.
  5. PRHeads

    Help Choosing a Cam/Converter- 9:1(ish) Stock Stroke 400

    I wouldn’t finalize the cam choice until you’re pretty well sure of what the rest of the short block/combo will consist of. If……. It ends up at very close to, or slightly over 9:1 CR, then I’d use a Comp XE268. If you end up closer to 8-8.5, I’d step down one size to the XE262.
  6. PRHeads

    How to destroy a 440

    I’d say the use of what are probably 50+ year old rockers and shafts on a freshly built HP 440 combo was obviously a bad call. The pic of the spacer in the wrong location in the pic in post #49 is evidence the assembler wasn’t very detail oriented and/or not very familiar with Mopar big blocks...
  7. PRHeads

    How to destroy a 440

    Not that it really matters at this point, especially since it will be getting new heads……. But, my take on whether or not they are Stealth heads(based on the currently posted pics)…… If you look at the end of the head in this pic, you can see the bosses for the alternator mount, like what...
  8. PRHeads

    Isky ductile iron rockers

    Here are mine……. Narrowed to Crane width…….. and lightened a bit. I couldn’t see the point in that big knob way out at the valve tip.
  9. PRHeads

    Isky ductile iron rockers

    I actually got a set of the reboxed Cranes…….that had “Crane” cast into them.
  10. PRHeads

    small block la 68 misurament valve seats

    I’m not sure what’s the norm over there, but here the seats are typically made with the correct press fit, when using a “standard” cutter. In other words, an SBI brand 1.687 seat would measure 1.6925. Which would give .0055 press if the hole was cut with a 1.687” cutter.
  11. PRHeads

    Isky ductile iron rockers

    I modified the rockers. Machined them down to be the same width as the Cranes. Either way will get the job done.
  12. PRHeads

    440 valve train question

    Exactly. As long as the pushrods and lifters are correct for each other, you’re good.
  13. PRHeads

    O2 sensor placement

    Yes. Make sure the gasket for the extension is good.
  14. PRHeads

    O2 sensor placement

    I would think any air pulled into the exhaust from the pan-evac would affect the readings. My experience with pan-evac systems and exhaust systems is they don’t play well together. If the O2 is fairly close to the open end of the pipe, the readings at less than WOT won’t be super...
  15. PRHeads

    The Imperial went out for a test

    Was that car set up as a Stocker? Is it still?
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