Forged pistons - Pirate4x4.Com : 4x4 and Off-Road Forum

SSIIprop · 01-08-2003, 09:11 PM

I am having a 345 long block built for me by my buddies shop. I have two routes I can go, a standard bore using lightened and polished rods and some type of Venolia pistons, or a .040 overbore using hypereutectic pistons and unmodified rods. I'm going with the Venolia pistons and lightened rods, but was curious about these pistons. The bore fits a 345 and the piston pin to deck distance is the same as a 345 piston but it has a completely flat top. It also uses different rings in different locations than the other 345 pistons. I looked on the underside and saw the number 400 on them. I was wondering if this is simply a custom set of pistons or made for a different motor.

Old Scout · 01-08-2003, 10:03 PM

When you say lightened rods, how much are you taking off?

Will the block take a "no" bore oversize? It's kind of rare not to need at least 8-10 thou in a 25+ year old motor.

IHWillys · 01-09-2003, 04:29 AM

Well I can't really say much about your specific pistons. I have a set of custom Venolia pistons in a 380 which resides in my '55 Poncho. They are stock Pontiac 400 bore, but for use with a shorter stroke crank and they are domed top(really high comp, premium doesn't cut it). I am happy with them, as I have pushed this engine hard, on/over the edge of detonation, for years now.

I agree with OS, if you are doing a performance build it's likely some cleanup of the bores would be beneficial. I have had good results with re-ringing when 'rebuilding' to stock specs, but if I'm spending $ on lightened rods and such, the block is getting new new holes, sleeves if necessary($$$).

If the pistons fit stock bore, pin location, and pin diameter, then they likely were made for it. Venolia might know...

Ken

SSIIprop · 01-09-2003, 06:38 PM

Not much material has been taken off the rods, just the small ridges on the sides and some off of the flat area on the bottom. I have been told the block will take a standard bore piston, although I did not see him measure it out. The block is in the machine shop getting new cam bearings and the cylinders honed right now. I will see what Venolia has to say about these pistons.

jhama78 · 01-10-2003, 12:10 PM

Hey mark which truck are ya building the engine for? Have you gotten any pics of the latest mods to the traveler? Take it easy man.

-j-rOd

SSIIprop · 01-10-2003, 06:26 PM

J-rod, This motor is going in the SSII. That 345 in the Traveler runs well enough for now. At least until I can throw down on a Caddy 500 I picked up a 4.57 geared Eaton rear for it and need to locate a matching front.

01-08-2003, 09:11 PM	#1 (permalink)
SSIIprop Registered User Join Date: Mar 2002 Member # 10582 Location: Chattanooga, TN Posts: 46	Forged pistons I am having a 345 long block built for me by my buddies shop. I have two routes I can go, a standard bore using lightened and polished rods and some type of Venolia pistons, or a .040 overbore using hypereutectic pistons and unmodified rods. I'm going with the Venolia pistons and lightened rods, but was curious about these pistons. The bore fits a 345 and the piston pin to deck distance is the same as a 345 piston but it has a completely flat top. It also uses different rings in different locations than the other 345 pistons. I looked on the underside and saw the number 400 on them. I was wondering if this is simply a custom set of pistons or made for a different motor. __________________ 79 SSII EFI 345, T19, SOA

01-08-2003, 10:03 PM	#2 (permalink)
Old Scout IH/Rover Moderator Join Date: Feb 2000 Member # 17 Location: Aptos,Ca Posts: 13,402	When you say lightened rods, how much are you taking off? Will the block take a "no" bore oversize? It's kind of rare not to need at least 8-10 thou in a 25+ year old motor. __________________ I like beer. On occasion, I will even drink beer to celebrate a major event such as the fall of communism or the fact that the refrigerator is still working." BUY MY BOAT http://www.pirate4x4.com/forum/misc-...e-history.html Last edited by Old Scout; 01-08-2003 at 10:04 PM.

01-09-2003, 06:38 PM	#4 (permalink)
SSIIprop Registered User Join Date: Mar 2002 Member # 10582 Location: Chattanooga, TN Posts: 46	Not much material has been taken off the rods, just the small ridges on the sides and some off of the flat area on the bottom. I have been told the block will take a standard bore piston, although I did not see him measure it out. The block is in the machine shop getting new cam bearings and the cylinders honed right now. I will see what Venolia has to say about these pistons. __________________ 79 SSII EFI 345, T19, SOA

01-10-2003, 12:10 PM	#5 (permalink)
jhama78 Registered User Join Date: Feb 2001 Member # 3377 Location: Eastern Shore, Va Posts: 3,904	Hey mark which truck are ya building the engine for? Have you gotten any pics of the latest mods to the traveler? Take it easy man. -j-rOd __________________ -j-rOd [COLOR="Lime"][SIZE="3"][B][URL="http://www.pirate4x4.com/forum/showthread.php?t=654042"]85 Roach Build Thread[/URL] [/SIZE][/B][/COLOR] [COLOR="Silver"][B] 84 Toy Farm Beater 85 Toy Trail Roach 223:1 85 Toy SR5 xcab DD 88 4Runner Fambly Beach Ride 07 Dodge 2500 4x4 Quad Cab, 5.9 CTD[/B][/COLOR] [B][COLOR="Lime"][SIZE="4"][FONT="Arial"]Nobody ever lays on their deathbed wishing they'd spent more time at work...[/FONT][/SIZE][/COLOR][/B]

01-10-2003, 06:26 PM	#6 (permalink)
SSIIprop Registered User Join Date: Mar 2002 Member # 10582 Location: Chattanooga, TN Posts: 46	J-rod, This motor is going in the SSII. That 345 in the Traveler runs well enough for now. At least until I can throw down on a Caddy 500 I picked up a 4.57 geared Eaton rear for it and need to locate a matching front. __________________ 79 SSII EFI 345, T19, SOA

01-09-2003, 04:29 AM	#3 (permalink)
IHWillys Registered User Join Date: Dec 2002 Member # 15721 Location: FC CO Posts: 48	Well I can't really say much about your specific pistons. I have a set of custom Venolia pistons in a 380 which resides in my '55 Poncho. They are stock Pontiac 400 bore, but for use with a shorter stroke crank and they are domed top(really high comp, premium doesn't cut it). I am happy with them, as I have pushed this engine hard, on/over the edge of detonation, for years now. I agree with OS, if you are doing a performance build it's likely some cleanup of the bores would be beneficial. I have had good results with re-ringing when 'rebuilding' to stock specs, but if I'm spending $ on lightened rods and such, the block is getting new new holes, sleeves if necessary($$$). If the pistons fit stock bore, pin location, and pin diameter, then they likely were made for it. Venolia might know... Ken

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