347 vs 374
05-10-2010, 11:03 AM
#1
TECH Enthusiast
Thread Starter
iTrader: (12)
Join Date: Oct 2008
Posts: 701
Likes: 0
Received 0 Likes
on
0 Posts
347 vs 374 Are there any cons to going to a longer stroke when building a LS1 for FI. I know a lot of guys stick with the 347 with the LS1 to keep the thicker walls but for a mild build would there be any harm in going with the longer stroke and punching her out to say around a 374.
05-10-2010, 10:08 PM
#3
TECH Enthusiast
Thread Starter
iTrader: (12)
Join Date: Oct 2008
Posts: 701
Likes: 0
Received 0 Likes
on
0 Posts
I searched and didnt see any thing that said any thing bad about going with the 374 on a FI set up. The bore would still be a 3.905 the same as it would be for a 347 the only diffrence would be the stroke of 3.900 vs 3.622 with the 347. Not saying your wrong just wanting to know why the longer stroke would hurt it.
05-11-2010, 08:31 PM
#5
TECH Enthusiast
Thread Starter
iTrader: (12)
Join Date: Oct 2008
Posts: 701
Likes: 0
Received 0 Likes
on
0 Posts
I have been told that the 383 is not good for turbo set ups. I dont know if the stroke is just too long or what it is. I was hoping some one would shine some light on the mistory for me.
05-11-2010, 08:38 PM
#6
10 Second Club
iTrader: (11)
Join Date: Apr 2003
Location: Surf City, NC
Posts: 1,151
Likes: 0
Received 0 Likes
on
0 Posts
I would stay with a 347 or if you wanna go bigger get a forged 370. All of the FI 383's I have ran into never responded well to boost for some reason. I dunno why either.
05-11-2010, 09:06 PM
#7
TECH Apprentice
Join Date: Sep 2005
Location: Bay Area, CA
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
There are alot of people on this form making really good numbers with a 383. Im thinking of going with a 383 on my build.... I especially like the low end torque a 383 gives out.
Trending Topics
05-12-2010, 12:24 AM
#8
370's are really hard to argue. There are countless 4th gen guys in the 9's with LQ9s, forged pistons and rods with good flowing heads cam combos(budget turbo kits, usually backyard engineered). If you want to go bigger then a 402-408 would be the next step.
05-12-2010, 12:44 PM
#9
TECH Apprentice
Join Date: Sep 2005
Location: Bay Area, CA
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
They are.... I personally dont want an iron block. But thats just a personal preferance.
05-13-2010, 07:11 AM
#13
TECH Enthusiast
iTrader: (7)
Join Date: Feb 2005
Location: new hudson,mi
Posts: 735
Likes: 0
Received 0 Likes
on
0 Posts
The one time it did make to track it was running on 7 cylinders as it had burnt plug wire found out after fact. Way wrong torque converter. However i do have a new bigger cam and a py3400 converter and a rossler trans brake to get installed now. Those numbers were on 20psi , made 750/750 ish on 14lbs .Hopefully cam will raise those numbers slighty and bring boost in faster.
05-13-2010, 07:17 AM
#14
The one time it did make to track it was running on 7 cylinders as it had burnt plug wire found out after fact. Way wrong torque converter. However i do have a new bigger cam and a py3400 converter and a rossler trans brake to get installed now. Those numbers were on 20psi , made 750/750 ish on 14lbs .Hopefully cam will raise those numbers slighty and bring boost in faster.
