Anyone know where to look up piston #'s with the compression values and specs? I had it somewhere but can't find it now.
Thanks Tim
thank you.
i have a set of L2377-60 and the list says ft;1 rel; chamfer. would these work for a blower engine with 990 heads? and what does the information mean? thanks
pat(slotracer) :coffeycup
i have a set of L2377-60 and the list says ft;1 rel; chamfer. would these work for a blower engine with 990 heads? and what does the information mean? thanks
pat(slotracer) :coffeycup
That means Flat top, one valve relief, and chamfered on the top edge. You'd have to know what heads to know what compression, but I don't think it's necessarily a good blower piston. It would be a step up from stock. It also depends on how much boost and HP you're trying to get out of it.
Here's what I get for compression:
100.9cc...8.83
106.9...8.46
109.4...8.32
116.9...7.92
119...7.82
Be careful when buying rings...it uses 5/64" top and second rings. It's also a pressed pin piston. Not really a "high performance" piston.
why would they not make a good blower piston if the boost was only 6-8 lbs?
also what head would be better 049's or 990's. a piston with that low of compression, what would you use it for? thanks
pat(slotracer) :messedup:
I cant find p/n L2307......
I got some of those. They are approx 12.5 to 1 comp ratio w/119cc chambers w/ untouched domes.
Mic the skirts for proper bore size.
They are for a 454 compression height (not 427).
why would they not make a good blower piston if the boost was only 6-8 lbs?
also what head would be better 049's or 990's. a piston with that low of compression, what would you use it for? thanks
pat(slotracer) :messedup:
Pat,
You say "only" 6-8 lbs. On gasoline, that's getting into boost levels requiring
more attention to detail. Still fairly low, but higher than "stock" can take.
This is basically a heavy duty replacement truck piston, that's why the low compression.
Here's a few issues with these pisatons in regards to anything over what they're designed for:
The first is that the top ring is too close to the top of the piston. With the chamfered edge, this makes the top edge of the piston even thinner, above the ring.
The 5/64" ring pack is heavy, and has a lot of drag. (However, the blower piston uses the same rings)
I think the oil ring grooves have a slot cut in them for oil passage instead of holes drilled. This makes the piston a lot weaker.
No grooves for spirolocks...pressed pin only. This means stock rods. 6-8 lbs boost, that's not the best idea, but it can be done.
I would imagine the tops of these pistons are relatively thin in comparison to a true high perf piston, to keep weight down.
Depending on the cam you're running, you may have to either clearance the intake notch in the piston, or that, and cut an ex. valve relief. There's probably not enough material in the top of this piston to do that safely with boost.
If you could look at this piston next to a true hi perf piston, you could see what I'm describing.
The blower piston is the 2453F.
I got some of those. They are approx 12.5 to 1 comp ratio w/119cc chambers w/ untouched domes.
Mic the skirts for proper bore size.
They are for a 454 compression height (not 427).
I built a .060+ 454 with those pistons, and with a true 119 cc chamber, zero deck, and a measured (poured) dome volume, I was only able to get 11.88:1. Getting the 12.5:1 that they advertise ain't easy.
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