MoparFins

Techical Discussions => Tech- - Engine => Topic started by: Leaburn Patey on November 18, 2009, 02:42:57 PM

Title: Need help piston shopping
Post by: Leaburn Patey on November 18, 2009, 02:42:57 PM
Yep.
Not much out there in the way of 383 pistons.
Just would like some feedback or any suggestions on what to use.
Also the BoaB's compression ratio is 9.2:1 and I would like to keep it that way or go up a wee bit---not down.
I am not good at "engine building math"
One piston supplier shows that I will have a CR of 8.7 with the 906 heads that have a 88CC open chamber.
Not really what I am after.
I want good power but she is gonna be a cruiser and not get the tar beaten out of it or get raced.
Yes,I have spoken to the Joisey Mob Boss--just would like to hear more opinions.
Any advice is appreciated and thanks in advance.
Title: Need help piston shopping
Post by: Leaburn Patey on November 18, 2009, 03:21:36 PM
(http://www.moparfins.com/forum/smileys/smiley1.gif)(http://www.moparfins.com/forum/smileys/smiley32.gif)
Title: Need help piston shopping
Post by: Herman on November 18, 2009, 03:38:35 PM


If you're set on using those open chambered heads, you might be able to use this one:
http://www.kb-silvolite.com/performance.php?action=details&P_id=327

Your CR will be a very loose estimate until you really measure the chamber size on the heads.
You'll also have to measure piston to heads clearance depending how far the dome pops above the deck.

If you want more CR you can always have the heads milled a bit more ofcourse.


BigBlockMopar2009-11-18 20:39:34
Title: Need help piston shopping
Post by: firedome on November 18, 2009, 03:57:53 PM
I would try to stay with stock compression, but that's just me, and I'm not a go-faster.

Title: Need help piston shopping
Post by: Steve on November 18, 2009, 05:02:38 PM
I told you to use 9.5's.  Then you can run regular gas and not have to worry abotu detonation problems.  Just make sure the RAD is a quality brass equal.  You already have the fan
Title: Need help piston shopping
Post by: Rich on November 18, 2009, 08:32:14 PM


I used these KB 9.7:1 pistons in my 383 with 88cc #346 heads:

 (http://chucker54.stores.yahoo.net/6ccsoliddome.html%20)http://chucker54.stores.yahoo.net/6ccsoliddome.html (http://chucker54.stores.yahoo.net/6ccsoliddome.html)
krautmaster2009-11-19 01:34:20
Title: Need help piston shopping
Post by: Stan Paralikis on November 19, 2009, 02:42:20 AM
still  say to go with the MP pistons from Summit!  (http://www.massmopar.com/yabb/Smilies/toetap05.gif)


(and stop listening to the wannabe boy-racers over at Moparts (http://www.moparfins.com/forum/smileys/smiley17.gif)) (http://www.moparfins.com/forum/smileys/smiley2.gif)
 
 
Quote
For budget or stock-style rebuilds, it's hard to beat the value of Mopar Performance cast pistons. Mopar Performance cast pistons are made from high-quality aluminum alloys and feature the OEM quality that you have come to trust. And because they're designed and manufactured to OEM specs, they'll provide improved reliability, performance, and a long service life.

(http://i45.tinypic.com/309581w.jpg)
 
(http://i49.tinypic.com/10zb51f.jpg)
 
Commando12009-11-19 09:25:13
Title: Need help piston shopping
Post by: Stan Paralikis on November 19, 2009, 03:13:51 AM
Or takes yer chances...
 
mopar 383 pistons - $175 (sun city) (http://inlandempire.craigslist.org/pts/1463159021.html)
 
(http://images.craigslist.org/3n93m43pf5O75T65Q29bc8df37a8a348f1e6f.jpg)
Title: Need help piston shopping
Post by: Leaburn Patey on November 19, 2009, 04:25:59 AM
Quote from: POLARACO
I told you to use 9.5's.  Then you can run regular gas and not have to worry abotu detonation problems.  Just make sure the RAD is a quality brass equal.  You already have the fan
Yep,26" rad and it is all real-$325.00 worth-- Not the cheapo tin/plastic aftermarket crap..
(http://i51.photobucket.com/albums/f385/68Cbarge/IMG_3426.jpg)
Title: Need help piston shopping
Post by: Leaburn Patey on November 19, 2009, 04:27:24 AM
Quote from: Commando1
Or takes yer chances...
 
mopar 383 pistons - $175 (sun city) (http://inlandempire.craigslist.org/pts/1463159021.html)
 
Thanks,but no thanks.
Going new.
Title: Need help piston shopping
Post by: firedome on November 19, 2009, 04:34:12 AM
Lea - where do you get the real brass Rad, do they have em for
318?  My rad shop wants $250 to recore my old one,  new isn't
that much more... but do want all brass... & where are they made?

Title: Need help piston shopping
Post by: Herman on November 19, 2009, 04:40:04 AM
The pistons on Summit say nothing about headchamber sizes, compression ratio, piston-top to deck height or pistonpin-distance.
For all you know you end up with smog-motor pistons which only create a slight draft inside the cylinders instead of a healthy compression ;)




Title: Need help piston shopping
Post by: Leaburn Patey on November 19, 2009, 05:19:56 AM
For all you know you end up with smog-motor pistons which only create a slight draft inside the cylinders instead of a healthy compression ;)
[/QUOTE]
I agree.
I also gave up.
I am taking the motor,rod assembly,crank,etc to a more professional shop.
I spoke to Rob at Bullet Engines.
http://www.bullet.on.ca/index.html (http://www.bullet.on.ca/index.html)
I should have gone there in the first place.
They will order in pistons,bore the block and balance the reciprocating assembly.They also want the heads to measure the cc's and valve to pistion clearance.He also will weigh the pistons,rods,etc.
He will have to hot tank (again) after the bore job,so another set of cam bearings wasted--even though they never were used.  
I am not good on engine math so I trust Rob and his staff's expertise.
They were instrumental in the building of my 440 back in 2004.
 
More than likely,I will let them build the motor for me since I lost confidence in myself and other shops.
Title: Need help piston shopping
Post by: Stan Paralikis on November 19, 2009, 07:35:33 AM
(http://www.moparfins.com/forum/smileys/smiley7.gif)Commando12009-11-19 12:39:05
Title: Need help piston shopping
Post by: firedome on November 19, 2009, 08:03:42 AM
Source for a brass radiator?

Title: Need help piston shopping
Post by: Leaburn Patey on November 19, 2009, 11:01:15 AM
Quote from: firedome
Source for a brass radiator?
I went to my local rad shop that has been in business for over 45 years.
http://www.profilecanada.com/companydetail.cfm?company=2414900_Pats_Radiator_Svc_Ltd_Kingston_ON (http://www.profilecanada.com/companydetail.cfm?company=2414900_Pats_Radiator_Svc_Ltd_Kingston_ON)
Title: Need help piston shopping
Post by: Snotty on November 19, 2009, 12:39:05 PM
I believe Kanter offers them....
Title: Need help piston shopping
Post by: Steve on November 19, 2009, 07:45:48 PM
Quote from: firedome
Lea - where do you get the real brass Rad, do they have em for 318?  My rad shop wants $250 to recore my old one,  new isn't that much more... but do want all brass... & where are they made?
 
Yep.  Easy.  Any Rad shop can recore yours with one.  Just need good tanks.  That's what was in it originally.  If those farmers can't get one, send her down.  I'll have my guy do it.  He only does classic rads now.
Title: Need help piston shopping
Post by: firedome on November 20, 2009, 04:18:15 AM

Ya, my local shop Eddies Rad can do it for $250, as I said, but for not
much more I can go all new, if the quality is there, and if I can find
out who actually makes them... everyone on the net has aluminum. 
I'll recore this one if I have to. (http://www.moparfins.com/forum/smileys/smiley9.gif)
firedome2009-11-20 09:18:45
Title: Need help piston shopping
Post by: Steve on November 20, 2009, 06:38:39 AM
That's what I suggest
Title: Need help piston shopping
Post by: firedome on November 20, 2009, 03:24:52 PM
I'm just worried the tank walls migh be thinned out after 38 yrs... Jeezum, is a 71 that old...? Gawllll Lee!! 

Title: Need help piston shopping
Post by: Stitcherbob on November 20, 2009, 04:15:35 PM
My buddy silver solders the tanks when he spies a thin area.....usually any rad guy who's been in the biz enough years knows where they get thin. That's called EXPERIENCE to you young-un's (http://www.moparfins.com/forum/smileys/smiley4.gif)