Forced Induction Superchargers | Turbochargers | Intercoolers

Keep 317s or Not?

Thread Tools
 
Search this Thread
 
Old 06-03-2012, 09:03 AM
  #1  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
zapp109's Avatar
 
Join Date: Jan 2011
Posts: 632
Likes: 0
Received 0 Likes on 0 Posts
Default Keep 317s or Not?

I might have a few extra dollars after i sell the 408w out of my mustang and was planning on running 317s with my setup. Ill do a fast run down and you can tell me what you think. Aiming for 700 HP on med/lower boost.. and 1000HP Fullout through t56.


lq4 shortblock
truck manifolds
317 Heads
Comp Turbo CT5 with a 80mm GT45 compressor wheel, triple ball bearing aluminum center section and a 79mm inconel turbine wheel. 1.15 AR divided ceramic coated turbine housing
Probe 4.00" 3.622" Stroke 2618 -16cc Forged Pistons
Eagle Forged 6.125" H-Beam Rods
Vic Jr manifold with rails
Low profile elbow
90MM wilson TB
78# Delphi Injectors
Aeromotive A1000 pump with filter and boost regulator
Comp Cam DUR @0.50 INT 226 EXH 236 Lobe SEP 114.0 Valve lift INT .584 EXH .601
ls2 timing chain
trickflow pushrods
ls7 lifters
patriot gold springs
Melling oil pump
Harland Sharp 1.7 rockers
50MM Tial BOV
Precision 46MM Wastegate
Snow stage 2 meth kit w/progressive controller
AEM wideband
AEM TruBoost controller
Unknown 3" inlet 4" thick intercooler
Old 06-03-2012, 01:16 PM
  #2  
TECH Resident
 
TheLS1Lover's Avatar
 
Join Date: Jan 2011
Location: Tulsa
Posts: 934
Received 0 Likes on 0 Posts

Default

If your aiming for 1Khp, get rid of them. They can make it and make power but to be safe get and aftermarket head with a thick deck. And why that Turbo? There are cheaper awesome quality Turbos out there.
Old 06-03-2012, 05:18 PM
  #3  
TECH Resident
iTrader: (12)
 
LSXFORMULA99's Avatar
 
Join Date: Nov 2007
Location: Alton IL.
Posts: 873
Likes: 0
Received 0 Likes on 0 Posts
Default

317s ftw
Old 06-03-2012, 05:19 PM
  #4  
Staging Lane
iTrader: (7)
 
compgto's Avatar
 
Join Date: Jan 2009
Posts: 89
Likes: 0
Received 0 Likes on 0 Posts

Default

I have that same turbo with an 84mm turbine. It's a bad mother. Im running 15lbs with it through 317's & LS9 head gaskets. Just bought a 2.5 bar map to turn it up some. At 15lbs you should make over 800 wheel through a T56.
Old 06-03-2012, 07:24 PM
  #5  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
zapp109's Avatar
 
Join Date: Jan 2011
Posts: 632
Likes: 0
Received 0 Likes on 0 Posts
Default

Yea the turbo i have is a bad bitch and it wont lag, great turbo and the guys that sell it stand behind their products.. I was just curious is there a step up from 317s sorta inexpensive heads? If i were to get another set...
Old 06-03-2012, 07:39 PM
  #6  
TECH Resident
 
TheLS1Lover's Avatar
 
Join Date: Jan 2011
Location: Tulsa
Posts: 934
Received 0 Likes on 0 Posts

Default

Used AFRs.
Old 06-03-2012, 08:08 PM
  #7  
TECH Apprentice
iTrader: (3)
 
86lxnotch's Avatar
 
Join Date: Dec 2011
Location: Malvern, PA
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
Default

see my sig for where im at on pumpgas.....cant wait to get a cam in it and some e85 or racegas. stock replacement gaskets and tty headbolts as well
Old 06-04-2012, 06:30 AM
  #8  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
zapp109's Avatar
 
Join Date: Jan 2011
Posts: 632
Likes: 0
Received 0 Likes on 0 Posts
Default

Yea those are great numbers for what your running, I was thinking used AFRs just wasnt sure if there was anything else out there i should look into.
Old 06-04-2012, 10:33 AM
  #9  
TECH Regular
iTrader: (2)
 
L92 fox's Avatar
 
Join Date: Mar 2010
Location: Wood river IL
Posts: 423
Likes: 0
Received 0 Likes on 0 Posts
Default

T56 ftw
Old 06-04-2012, 10:53 AM
  #10  
TECH Fanatic
iTrader: (5)
 
99SS-T's Avatar
 
Join Date: Apr 2005
Location: Phoenix AZ
Posts: 1,005
Likes: 0
Received 0 Likes on 0 Posts

Default

There is a few companies out there now that make a great aftermarket head. I think afr is one of the first so they would be your best bet for finding a cheaper head as you can find an older one. Not that it gets much cheaper going used but better then brand new. But money is money!
I got my 235cc's for 1800 from the for sale section here. have yet to start the engine but they look great!
GL
Old 06-04-2012, 11:01 AM
  #11  
TECH Fanatic
iTrader: (18)
 
71 chevy's Avatar
 
Join Date: May 2008
Location: Dallas, Tejas
Posts: 1,608
Likes: 0
Received 1 Like on 1 Post
Default

keep the 317s
Old 06-04-2012, 11:37 AM
  #12  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
zapp109's Avatar
 
Join Date: Jan 2011
Posts: 632
Likes: 0
Received 0 Likes on 0 Posts
Default

Seems like a lot of mixed opinions. 1 question I have maybe someone knows since I'm not very technical with compression. Right now with my setup I was told it should be around 8:8:1 compression with 317. Would a set of afr heads bump it up or lower it ??
Old 06-04-2012, 11:54 AM
  #13  
Staging Lane
iTrader: (3)
 
408COUPE's Avatar
 
Join Date: Jan 2009
Posts: 54
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by zapp109
Seems like a lot of mixed opinions. 1 question I have maybe someone knows since I'm not very technical with compression. Right now with my setup I was told it should be around 8:8:1 compression with 317. Would a set of afr heads bump it up or lower it ??
The cc of the head and the head gasket will determine whether the compression ratio will stay the same or change. So naturally if you match the cc and keep the same type gasket your compression will stay the same. The higher numerical number the cc head (from whatever the 317's are) will lower your compression and visa versa... This is referring to static compression.
Old 06-04-2012, 12:07 PM
  #14  
TECH Fanatic
iTrader: (5)
 
99SS-T's Avatar
 
Join Date: Apr 2005
Location: Phoenix AZ
Posts: 1,005
Likes: 0
Received 0 Likes on 0 Posts

Default

the 317 heads are 72cc from GM. and 72 is the largest number that i have seen for heads. Not that there isnt anything bigger but id guess they are out of the ordinary. The ones that I bought are 72cc as cast then a little porting to smooth it out so maybe a few more cc there. It took a bit of looking to find a set for 72 as most people use the piston to lower cc and then stick with a mid 60's cc head.
The 8.8 you believe you are currently running is well into the safe area so if you got something smaller it wouldn't be so bad.
GL
Old 06-04-2012, 02:46 PM
  #15  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
zapp109's Avatar
 
Join Date: Jan 2011
Posts: 632
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by 99SS-T
the 317 heads are 72cc from GM. and 72 is the largest number that i have seen for heads. Not that there isnt anything bigger but id guess they are out of the ordinary. The ones that I bought are 72cc as cast then a little porting to smooth it out so maybe a few more cc there. It took a bit of looking to find a set for 72 as most people use the piston to lower cc and then stick with a mid 60's cc head.
The 8.8 you believe you are currently running is well into the safe area so if you got something smaller it wouldn't be so bad.
GL
Great info THANKS
Old 06-04-2012, 04:27 PM
  #16  
TECH Fanatic
iTrader: (16)
 
HydroStream6's Avatar
 
Join Date: Nov 2004
Location: Rochester, NY
Posts: 1,273
Likes: 0
Received 3 Likes on 3 Posts

Default

This is easy. If you can afford an aftermarket casting, buy heads. If you cannot, use 243s or 317s with LS9 gaskets. I'm making 1k flywheel through 317s, but I still wish I had thicker heads so I could push it a bit.
Old 06-04-2012, 05:26 PM
  #17  
TECH Enthusiast
Thread Starter
iTrader: (13)
 
zapp109's Avatar
 
Join Date: Jan 2011
Posts: 632
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by HydroStream6
This is easy. If you can afford an aftermarket casting, buy heads. If you cannot, use 243s or 317s with LS9 gaskets. I'm making 1k flywheel through 317s, but I still wish I had thicker heads so I could push it a bit.
Yea thats what Im affraid of, getting to my limit then wanting more. The engine im building could hold more. But also thinking maybe get an extra 50-100 HP by putting better head on.. I was planning on LS9 gaskets for sure, with aftermarket head like AFR people still using those gaskets or do you nedd other gaskets for some reason?
Old 06-04-2012, 05:35 PM
  #18  
TECH Veteran
iTrader: (21)
 
1CAMWNDR's Avatar
 
Join Date: Nov 2001
Posts: 4,247
Likes: 0
Received 2 Likes on 2 Posts

Default

317s with good valves and valve job will make more power than you can probably hook without a serious drag suspension.
Old 06-04-2012, 05:51 PM
  #19  
TECH Addict
iTrader: (16)
 
I8UR4RD's Avatar
 
Join Date: Oct 2010
Location: Bama
Posts: 2,593
Likes: 0
Received 2 Likes on 2 Posts
Default

Well, you got all that dough in the motor, and its turbo, etc etc....and you wanna slap on some thin deck el cheapo heads on it? not me. the PRC 237's are the way I went considering they were spec'd for the larger motors, and they are a few hundred less than the AFR, but flow just as well, and the deck is thick as hell. Over 3/4 in some areas according to what I have read. Not cheap, but reasonable.

http://texas-speed.com/p-1171-prc-23...der-heads.aspx

nice *** heads too. not a ton of info on them in comparison to afr, but hey, everyone has afr and tf just about, and even if that is for a reason, I like to be a guinea pig from time to time.

Last edited by I8UR4RD; 06-04-2012 at 05:57 PM.
Old 06-04-2012, 06:17 PM
  #20  
TECH Fanatic
iTrader: (16)
 
HydroStream6's Avatar
 
Join Date: Nov 2004
Location: Rochester, NY
Posts: 1,273
Likes: 0
Received 3 Likes on 3 Posts

Default

I'm bolting on PRC215s soon, got them in the garage. After I dyno I'll provide some more insight. I'm anticipating 75ish HP just from the swap and who knows what with more boost.


Quick Reply: Keep 317s or Not?



All times are GMT -5. The time now is 11:57 PM.