Pistons for a 30 over 350

dennisM

Amateur Racer
Apr 2, 2009
224
0
16
Bessemer, PA
The new guy here asking a question. I found a list of piston and ring kits at summit:

http://store.summitracing.com/egnsearch.asp?RC=100&N=700+4294925232+4294839001+4294852538+4294791253+4294908216+4294908395+4294840140+115&Ntt=&Ntk=&Ns=P_SRE_DisplayPrice%7C0&rsview=sku

Which one should I get? I see that different pistons will give me different compression. I don't know what to go for. Just want to run it on premium pump gas. Will be running Vortec heads.

Too bad a stroker kit is just out of my price range. :cry:
 

madmoose63

Frequent Racer
Apr 20, 2008
449
0
0
Bryan,Ohio
If you are just going to cruise it with occasional track time i would run the hyper pistons with 9 to 1 compression...imo
 

bottlesempty

Amateur Racer
Apr 22, 2007
246
0
0
southern maine
x2on hyper if runnig naturallyaspiratedIlike a little compression but the stock springs on a vortec head wont support any real llift so cam choices are very limited unless you pgrade the springs Irun93octane with 11.5compression with a pretty aggresive camthatwill bleed off some compression I've had no issues would go10: 1 for your comboconsidering your r cam choices atleas t 9.5 9.1 may be a little soggy down low
 

dennisM

Amateur Racer
Thread starter
Apr 2, 2009
224
0
16
Bessemer, PA
Haven't bought heads yet. Got cam last week (Comp's XE268H). This was before I decided to go 30 over. Wish I could get Dart heads, but they're just out of my budget reach.
 

holtjohn

Frequent Racer
Oct 15, 2008
516
0
0
your gonna want to shot for 9.0 to 9.5 with that cam. I have that cam in my street motor and I love it, I think you will be happy with that cam too. That cam is gonna push the limits of the stock valve spring vortec heads just to let you know.
 

dennisM

Amateur Racer
Thread starter
Apr 2, 2009
224
0
16
Bessemer, PA
Thanks for the replies. What do I look for in the product details for the compression? For instance this one: http://store.summitracing.com/partdetail.asp?part=TRW-8KH345NCP30&autoview=sku
holtjohn said:
your gonna want to shot for 9.0 to 9.5 with that cam. I have that cam in my street motor and I love it, I think you will be happy with that cam too. That cam is gonna push the limits of the stock valve spring vortec heads just to let you know.

Yea I know. Talked to a number of people and they said as long as I buy them new (which I am) it will be ok. Maybe later on I'll get those nice Iron Eagle Platinums someday ;)
 

ProJunk

Dragway Regular
Sep 12, 2006
902
0
0
Glendale, AZ
The Vortec head has a very efficient combustion chamber and is tolerant of higher compression ratios on pump gas. I'd shoot for a flat-top piston, preferably with only two valve reliefs to get as much compression with the flat-top as possible. Depending on your deck height & head gasket thickness, you should be able to achieve anywhere from 9.5-10:1 with this type of piston, which should be ideal. Retainer-to-valve-guide clearance can be an issue at max lift with Vortec heads, so check that carefully during mock-up. You'll want at least .060" clearance between the bottom of the retainer & top of the valve guide at max lift. This is much easier to check if you install a set of lightweight checking springs on one pair of valves. A set of stock LSx beehive valve springs & retainers is a cheap & easy drop-in upgrade for the Vortec heads that will give you more spring pressure, more coil bind clearance, and more retainer-to-guide clearance.
 

360demonRT

Frequent Racer
Jul 13, 2008
381
0
0
central Ky
link to the above mentioned beehive springs? or are they a stock deal. i hope one day to have enough money to put my pos together lol
 

ProJunk

Dragway Regular
Sep 12, 2006
902
0
0
Glendale, AZ
Stock LSx valve springs & retainers, especially the LS-2/LS-6 springs, are a good cheap upgrade for Vortec or just about any conventional SBC cylinder head. You could also use aftermarket LSx beehive springs such as the popular Comp Cams 26918-16 springs, but those don't really fit into the "budget" category for cheap upgrades. SI Valves has a good beehive for reasonable money that offers a bit more spring pressure & allows up to .610" lift under part # VS1118-16.
 

dennisM

Amateur Racer
Thread starter
Apr 2, 2009
224
0
16
Bessemer, PA
I'll definitely look into getting those springs.

I want to reuse the rods from my stock pistons. If I wanted to get the ones with the two valve reliefs, will I need to get the rods machined due to the floater pins?
 

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