New Build Trickflow 190 and quench

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famous bob said:
I don't get this , how can opening a head up create quench ?? U need a flat spot on the heads and a flat corresponding part of the piston to create quench. Best is usually about .035-.040 .
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Hey FB, the OP is thinking he needs to open up the chambers to keep the SCR under control when he puts a piston up close enough to the flats on the head surface around the chamber to get quench. But as above, he can do this all in piston selection and block decking.
 
Wow that's really helpful! Thank you very much

nm9stheham said:
If you want that static CR with a 4" stroke and 60 cc chambers, then do this:
  • Use the ICON IC9978 piston from their FHR forged line. 13 cc dish + eyebrows, and CH of 1.450"
  • Cut deck to get to that SCR and a decent quench gap with those 60 cc chambers with no chamber cutting
    • Cut block deck by approx .022" to get the piston tops .005" below deck. SCR will then be 11.1 with a Felpro 1008 head gasket and quench gap of .044"
    • Or, cut deck by approx .027" to get piston tops at zero deck. SCR will be then 11.2 with the Felpro 1008 head gasket and .039" quench gap
FWIW: Dynamic CR will be around 9.0 with those cam specs at 104 ICL. Don't know your exact elevation but at 500' cranking compression computes out to 185 psi + or -; the fast ramps on that particular cam (optimized for the .904 lifters) would make me thing it will be more on the + side.

Ought to be exciting! LOL
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You're welcome. It looks very doable. I added a bit more info in my post that you might want to check out.
 
Yea that helps. I have always thought of quench against a flattop type piston or a quench dome type piston like my brother has in his 440.


nm9stheham said:
You're welcome. It looks very doable. I added a bit more info in my post that you might want to check out.
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Ivoryk3ys78 said:
Can't the cc's in a head be upped by opening it up some? I have never done head work but my understanding was you could do that.

I wouldn't have it done on these heads I just meant to get a quench at a lower compression my understanding is that that is the only option. That was really the origin of my question.
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opening up the combustion chamber size doe not create quench . I think u might not understand what quench is ---------
 
Do quench
do the dished piston
shorter cam will be fine
KISS
the slightly lower compression and quench will be easier to tune and more tolerant of timing or a tank of bad gas or carbon buildup down the road
 
Wyrmrider said:
the slightly lower compression and quench will be easier to tune and more tolerant of timing or a tank of bad gas or carbon buildup down the road
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Hence my tongue-in-cheek comment of 'Sounds exciting!' LOL This engine tune and operation won't be for the lazy.....but it'll sure have good low RPM torque.
 
Opening up the chambers can be done to increase flow
and/or
to add some cc's
I usually do for both with the seat cutter and just a slight blend by hand
also to even out the cc's of the chambers
in this case it's much easier to add compression than to take it away
so start a little lower than you think you need to
and a little shorter on the cam
fewer customer come backs that way
do it the other way around and it was always may fault
 
famous bob said:
I don't get this , how can opening a head up create quench ?? U need a flat spot on the heads and a flat corresponding part of the piston to create quench. Best is usually about .035-.040 .
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Easy, because there is still an insistence on confusing "squish" with "quench", unless the OP has pop-ups,...He is going to have to shoot for a larger quench zone to be safe with that .080" gasket.
 
famous bob said:
opening up the combustion chamber size doe not create quench . I think u might not understand what quench is ---------
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I was not taying that opening up the chamber created quench, or at least I was not intending to. It was merely the only way I could think of to lower the compression to an acceptable level and still remain in a squeeze zone tight enough to create a quench effect(.035-.050 area) with a flat top piston with valve notches. I had not considered what nm9stheham had suggested. Using pistons and creating a squish along the sides and focusing on that area for the quench. I also didn't know of a piston that had that small of an amount of cc in the hole. The ones I saw were all around 20cc.
 
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What I have decided on is to use the pistons nm9stheham suggested with a .039 gasket at 0 deck. The camshaft will be the Howards I originally posted the 712712-08. I will have to work on making sure it runs cool and maybe back off the timing a couple points. The worse case scenario is I will add a little Torco unleaded fuel accelerator in each tank. They are 20 bucks on amazon for a 32 oz bottle so not bad. I am thinking it will be okay with the aluminum heads. David Vizard suggested a max cranking pressure of 200 and 190 being a safe target and no distinctions made regarding head material. Dave Hughes suggested 165 for iron heads and 195 for aluminum heads. This should put me at at a max of around 190 and with some quench effect happening and the aluminum heads I am thinking it will be okay with 92 octane.

Looking forward to the Trickflow intake to come out. I called Trickflow and Howard told me around the end of September.
 
Ivoryk3ys78 said:
What I have decided on is to use the pistons nm9stheham suggested with a .039 gasket at 0 deck. The camshaft will be the Howards I originally posted the 712712-08. I will have to work on making sure it runs cool and maybe back off the timing a couple points. The worse case scenario is I will add a little Torco unleaded fuel accelerator in each tank. They are 20 bucks on amazon for a 32 oz bottle so not bad. I am thinking it will be okay with the aluminum heads. David Vizard suggested a max cranking pressure of 200 and 190 being a safe target and no distinctions made regarding head material. Dave Hughes suggested 165 for iron heads and 195 for aluminum heads. This should put me at at a max of around 190 and with some quench effect happening and the aluminum heads I am thinking it will be okay with 92 octane.

Looking forward to the Trickflow intake to come out. I called Trickflow and Howard told me around the end of September.
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Torco Accelerator is great stuff. If you can use the leaded, you can use less of it.

That said, there is no reason you shouldn't be able to run pump gas without issues.

Head material and cranking compression mean almost nothing related to detonation.
 
yellow rose said:
Torco Accelerator is great stuff. If you can use the leaded, you can use less of it.

That said, there is no reason you shouldn't be able to run pump gas without issues.

Head material and cranking compression mean almost nothing related to detonation.
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interesting, say a 11 to one , cast iron headed engine built exactly the same clearances and dimensions as an alum. headed engine , same everything except the heads mat`l .
Why will the alum.headed engine run good on 91 oct. , and the cast headed one wont w/o slowing the timing down , if at all w/o detonating ?
 
Ivoryk3ys78 said:
What I have decided on is to use the pistons nm9stheham suggested with a .039 gasket at 0 deck. The camshaft will be the Howards I originally posted the 712712-08. I will have to work on making sure it runs cool and maybe back off the timing a couple points. The worse case scenario is I will add a little Torco unleaded fuel accelerator in each tank. They are 20 bucks on amazon for a 32 oz bottle so not bad. I am thinking it will be okay with the aluminum heads. David Vizard suggested a max cranking pressure of 200 and 190 being a safe target and no distinctions made regarding head material. Dave Hughes suggested 165 for iron heads and 195 for aluminum heads. This should put me at at a max of around 190 and with some quench effect happening and the aluminum heads I am thinking it will be okay with 92 octane.

Looking forward to the Trickflow intake to come out. I called Trickflow and Howard told me around the end of September.
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You have some 'outs' and aids as listed. Some have commented about 91 octane being more difficult to run detonation free than 93. I've accepted that as real based on their say-so. Where 92 falls???

I have not commented and have not opinion but is there an objective to push the cylinder pressures up? Just to keep the low RPM torque up with a bigger cam? (BTW, I like higher compression builds myself so no objections here.)
 
nm9stheham said:
You have some 'outs' and aids as listed. Some have commented about 91 octane being more difficult to run detonation free than 93. I've accepted that as real based on their say-so. Where 92 falls???

I have not commented and have not opinion but is there an objective to push the cylinder pressures up? Just to keep the low RPM torque up with a bigger cam? (BTW, I like higher compression builds myself so no objections here.)
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I would say there are two reasons I wanted to run the compression on the higher side. One being as you said to keep the low rpm range quite strong and keep the engine as efficient as possible. The other being if I lowered the compression very much from the 11.2 with the .039 gasket and 0 deck along the outer edge of the pistons and the -13 chamber dish and valve reliefs I would also be diminishing the possible benefit I was getting toward more efficient/better burning combustion and the anti detonation benefits of quench. So I could go with quite a thick gasket or the piston more in the hole and lower it to 10.7 or even 10.5 I would also remove the benefit of quench and I don't think anyone could tell me for certain that a 10.7 engine without a quench effect would be less prone to detonation then an 11.2 engine with a quench effect assuming everything else being equal.

That and I see my dads 383 in his RR run detonation free with pretty much exactly that compression. He has heavily ported closed chamber heads (915) and an ultradyne solid roller with I believe 256@050. So coming out to the same compression and my combo also having a closed chamber head and a cam right around the same size gives me some confidence.
 
OK, thanks No problem here... just curious. I'm honestly a bit lazy when it come to doing distributor curves (messed with that stuff decades ago) so I stick with a mere 10:1 SCR LOL

BTW, you mentioned the Ultradyne cam in the 383.... that name makes me think of older slower ramp grinds..... maybe someone will chime in to confirm or deny that for a roller grind. Your Howards solid might be a lot faster ramp cam, so might to be able to get more air into the engine with the same .050" duration, and perhaps with some better lift numbers. So your engine may have higher 'effective' compression ratio, or dynamic CR., that may push the CR limits. I sure would not go there without quench.

As said, it should be exciting! I look forward to hearing how it goes. Sounds like you have your eyes open on the issues.
 
I don't think anyone could tell me for certain that a 10.7 engine without a quench effect would be less prone to detonation then an 11.2 engine with a quench effect assuming everything else being equal.

I can tell you
go with the 11.2 and tune it
get YR to help if you need to
gotta watch your cam timing
want an expert opinion ask Mike Jones
get a custom solid flat tappet he recommends
 
famous bob said:
interesting, say a 11 to one , cast iron headed engine built exactly the same clearances and dimensions as an alum. headed engine , same everything except the heads mat`l .
Why will the alum.headed engine run good on 91 oct. , and the cast headed one wont w/o slowing the timing down , if at all w/o detonating ?
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My money goes to the more modern and probably more efficient combustion chamber design on the aluminum head gives you more margin before detonation happens. You are not going to convince me that aluminum handles/dissipates the near instantaneous thermal shock produced by the combustion cycle faster than CI and that makes the difference. If you had heads made of each material with identical features, you probably couldn't tell them apart without good instrumentation.
 
End combustion temps getting too high is why the detonation problems usually rear their head. Lower AL chamber temps mean lower charge heating during the compression cycle, and a lower starting combustion temp means lower end temp... all other things being equal. So it is not any instantaneous heating differences from the head material as much as the charge heating that takes place before combustion.
 
you are both right
check the advance required for a clue to how good a combustion chamber is
302 -308- magnum and modern aluminum are better than 67 heads and way better than open chamber
 
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