fritz1990
Dedicated Member
Posts: 6560
Age: 61
Loc: Kansas
Reg: 02-16-03
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03-18-23 06:41 PM - Post#2855906
In response to 65_Impala
Listen to 65Impala he is spot on! The quench and compression height is important to a good running engine. If you don’t know how to measure these things, ask. IMHO I would bore it, then you would have nice round bores. Don’t put new pistons in an out of round bore. My 5 cents.
Regards, Jeff
1998 K1500 6.5 Coal burner
1965 C10 with 498 BBC AFR Heads
1964 C10 Ran 348W for 6 years, now SBC.
Corvettes owned: '74 '77 '78 L82 Silver Anniversary, 2002 LS1, 2007 C6 Love this one! Now have 2014 C7
Don't have a nervous come together!
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CNC BLOCKS N/E
Senior Member
Posts: 989
Loc: NORTH EAST
Reg: 12-12-03
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03-19-23 09:11 AM - Post#2855920
In response to Tony1963
There is no real way to measure alignment between housing bores follow the insurrections that come with you ARP kit
Torque plate hone is a must if you want to achieve good ring seal
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bobb
Super Senior Member
Posts: 6249
Loc: paradise
Reg: 09-05-03
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03-19-23 12:24 PM - Post#2855924
In response to DuramaxLLY
i hope you are doing your homework. as noted quench is critical, as is piston design. dog dish pistons are junk junk junk. the heads and cam you choose will determine the rpm power band you end up with. look at vizard and holder vortec videos on you tube.
| 70 L camino, grampa engine, g-force 5 spd, road rage suspension. Pray first before all else fails. |
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Tony1963
Frequent Contributor
Posts: 2046
Loc: Orlando Florida
Reg: 07-09-18
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03-19-23 01:03 PM - Post#2855931
In response to 65_Impala
I've used cast flat-top pistons before without issues. But, I wasn't trying to build a 400 HP engine, either.
I suspect that he is looking for a budget upgrade in performance, thus, I steered him toward the cast piston if needed.
| People fear change because it threatens what they know, or what they claim to know. |
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1983G20Van
Super Senior Member
Posts: 3987
Loc: Hurst, Texas, USA
Reg: 11-13-02
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03-19-23 07:23 PM - Post#2855940
In response to DuramaxLLY
Alright finally got around to taking it to the machine shop. It’s already bored .30 over. I want to just hone it but if not we’ll go to .40.
Gonna keep the crank and rods. I’ll order some flat top hypereutectic pistons. Their weight will be about the same as stock so I shouldn’t need to rebalance.
I’ll ARP stud the bottom end. Line Hone is expensive so if the caps still line up nice I might skip that.
For heads, he recommended staying 185cc and below for better responsiveness on the street. Once I pick out a set of heads we’ll match the correct cam.
Now let’s see if I can stay under budget!
As for smaller than 185cc it is a pipe dream that they make more torque. I put 200cc advertised (more like 195cc in reality) aluminum heads on my old 350 Vortec in my heavy Express van when the garbage mexican Vortecs cracked. They made noticeably more power everywhere. When I built the 383 I had Lloyd Elliot port a set of those same heads for it. Up to about 210-215cc (varies a bit port to port). They flow ~300 cfm @ 0.600 and I have 0.578 lift. I make ~500 hp at the crank with a 218/228 @ 0.050 roller cam cut on a 108 LSA and it leaps to life. Loads of torque. The better the heads flow the smaller the cam can be to make a given power. The smaller the cam, the more off-idle torque, throttle response and fuel mileage you will have. The cam specs above make peak power at 5,600 rpm and peak torque about 3,500 rpm. Its over 500 ft/lbs at 3,500. The 383 moves my Express that weighs just shy of 7,000 lbs like it is 3,000 lbs lighter.
| 1983 G20 Van, 350 TPI, Ported 906 Vortecs, Edelbrock 3817 Base, ASM oversize runners. Reed Custom Roller cam, 700r4, 12 bolt with 3.08 gears, Doug Thorley Tri-Y headers, true duals |
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65_Impala
Very Senior Member
Posts: 4957
Reg: 12-29-02
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03-20-23 04:26 AM - Post#2855948
In response to Tony1963
I've used cast flat-top pistons before without issues. But, I wasn't trying to build a 400 HP engine, either.
I suspect that he is looking for a budget upgrade in performance, thus, I steered him toward the cast piston if needed.
Which today is a hypereutectic piston. You obviously don't know what you're talking about anymore if you think cast pistons that are not hypereutectic is still a thing people should use.
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 Shepherd
Valued Contributor
Posts: 2843
Loc: Lake George, NY
Reg: 11-11-15
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03-20-23 05:55 AM - Post#2855949
In response to 65_Impala
You can still buy "plain jane" cheaper regular cast pistons, next step up are the better Hypereutectic cast pistons that are superior to regular cast and can handle much more power. Pretty sure we all know this.
Edited by Shepherd on 03-20-23 05:56 AM. Reason for edit: No reason given.
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65_Impala
Very Senior Member
Posts: 4957
Reg: 12-29-02
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03-20-23 08:46 AM - Post#2855950
In response to Shepherd
You can still buy "plain jane" cheaper regular cast pistons, next step up are the better Hypereutectic cast pistons that are superior to regular cast and can handle much more power. Pretty sure we all know this.
Enlighten me then. Where do you get a 4.030" bore, 1.56" compression height cast piston then that are so much cheaper than a set of hypereutectic it's even worth considering them?
Sets of 8 Hypereutectic pistons for a 350 start at around $195.
Sets of 8 cast non hypereutectic pistons for a 350 start at around $180 and they have the wrong compression height.
I never said plain cast pistons are no longer available.
But, it is complete stupidity to use plain cast pistons in a 350 small block build that you are doing as a performance build.
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Shepherd
Valued Contributor
Posts: 2843
Loc: Lake George, NY
Reg: 11-11-15
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03-20-23 10:29 AM - Post#2855958
In response to 65_Impala
I would never use basic cast pistons in any build, I wasn't challenging anyone's ideas, just info in case someone wasn't aware of the different types of cast pistons.
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