Is Quench Worth the trouble??

[1968rt]

I have a motor built using TRW 2266 pistons and the MP .528 mechanical cam. According to the United Engine Compression Calculator, I have 9.9 static and 9.05 dynamic compression with 78cc  (915) heads. The TRW 2355s will give me 10.6 static and 9.7 dynamic. Im not worried about the compression difference, Im worried about the quench. With the 2266s in the hole .080 there is none and Im worried about detonation. The 2355s will give me a perfect .040 with the steel shim gasket. With the cost of the pistons and the rebalance Im looking at about $600. Is it worth it??

[sr71mopar]

It couldnt hurt.

[NYrr496]

I say it's worth it. 600 dollars spent to do it right the first time will save a world of heartache in the long run. How many miles you plan on this thing staying together? Detonation beats up the pistons, bearings, could possibly break the crank.... Not to mention the emissions will be cleaner.

[440 ValiantCharger]

I think it is worth it, i m ditching the 906 heads and buying 440 source heads when available, flat top pistons with a 0 decked block, this is my main goal to achieve effective and correct quench, this costs more than the standard setup but definitely worth it.

[67Satty]

  I'm kinda in the same boat.  I've got the 2355s at zero deck with open-chambered 452s right now with the plan of getting close-chambered 440Source heads in the future when they come out.

[QK TIME]

I think its definatly worth it. When I built My 440 I bought KB 184 quench domes to get the effect on My open chamber 906,s. I want to switch to Eddies in the future and Ill  just mill 'em down.

[375InStroke]

Unless you want 8:1 compression and have the power of a late '70s POS, then no, it isn't worth it.  I think it's as important as ring gap, correct A/F ratio, bearing clearance...  Sometimes with a motor that pings, installing a thicker head gasket actually makes things worse.

[340fyd]

That's what I'm trying to do.  I'm in the planning stage right now.  I'm wanting a 9 to 1 quench motor with 915 heads for a daily driver and some towing ever now and then.  It looks like I"m going to use a 440 an put it in my 86 2wd Ramcharger.  I've got a 400 block that I thought about putting my steel 440 crank in to do this, but I'm not finding the piston with quench and that low of compression to use for this build.  Been looking at all kinds of pistons for both and it looks like the KB184 for the 440 block, that puts me close to that depending on gasket thickness and how much I mill off to get quench.

Lee

[illfish]

.080 in the hole is alot and you will lose a lot of power.  The end goal we all want is reduced ignition timing(run lower octane fuel and thus make more power), more efficient combustion burn and decreased detonation.  It's definitely worth it.

[PureGTS]

The whole idea is to get the air/fuel that can hide under the open area to come out and start the mix spinning or to be disturbed as greatly as possible. Think of it as a fuel/air bomb, which it kinda is really, if the mix isn't mixed and moving about it just goes "poof" from any heat source rather than "bang" from a directed timed spark. If you've watched the engine build offs competition in the mags, alot of the engines being built are at levels that would normally ping with the use of regular (non-race) gas. But, because of the manipulation of the quench area, they get the power of higher compression by using the air disturbing features of quench to cool the mix by way of moving it around, rather than letting it sit, and focusing it in the combustion chamber by the spark plug.

[1968rt]

Thanks for the input guys, you all helped alot

[ucdcrush]

Those pistons have been around a long time, lots of motors built with them, are most/all of them pinging detonating and eating themselves alive?

[383man]

Yes !   I run 10.0 comp wth a .042 quench in the 440 in my 63.   I use 38 total all in by 2000 and run fine on 93 pump.  In fact it runs fine on 92 pump also.  Ron