1969 chevelle 396 350 hp specs [Archive] - Chevelle Tech

: 1969 chevelle 396 350 hp specs


68impala
Aug 21st, 06, 6:50 PM
Hello, I am new here, just came over from the camaro site. I have a 1969 396 350hp engine from a chevelle (code is JC) I was wondering what is the difference in the motor compared to a 325 hp motor. thanks

1badss396
Aug 21st, 06, 7:21 PM
air cleaner decal extra 25 hp
The extra 25 hp
Carb is different I think and intake is different?
I have the same motor for my 69 vert, so I dont really know what else is different, someone else will chime in and tell us more.

AZCamino
Aug 21st, 06, 7:36 PM
Basically, the cam and valve springs were different, with minor differences in carburetor and distributor specifications. Intakes, heads, blocks, and pistons were the same. 350HP used same valve springs as 375HP.
Bruce

Dean
Aug 21st, 06, 8:01 PM
Air cleaner
325 hp was closed with snorkel, 350 hp was open element.

mr 4 speed
Aug 21st, 06, 8:01 PM
Basically, the cam and valve springs were different, with minor differences in carburetor and distributor specifications. Intakes, heads, blocks, and pistons were the same. 350HP used same valve springs as 375HP.
Bruce


that is 100% correct

68impala
Aug 21st, 06, 9:42 PM
Thanks alot, I didn't think there was a difference. Is the crank cast or steel. This is a 2-bolt block. If anyone is near Youngstown Ohio and needs this engine I would consider selling it to some one who really needs it.

Junkyard Dawg
Aug 22nd, 06, 12:48 AM
It's probably cast.

von
Aug 22nd, 06, 7:04 AM
Thanks alot, I didn't think there was a difference. Is the crank cast or steel. This is a 2-bolt block. If anyone is near Youngstown Ohio and needs this engine I would consider selling it to some one who really needs it.
There's the other difference. '69 350 hp has a forged crank vs a cast crank for the 325 hp.

SWHEATON
Aug 22nd, 06, 8:35 AM
AZCAMINO & DEAN ARE 100% correct.

FYI,i know for sure the 69 & 70 396/325hp & 350hp motors both had nodular iron cranks from the factory,396/375's had steel cranks.

Its the earlier like 1966-67 396/350hp & 360hp motors that had steel cranks (along with the 396/375hp & 1965 Z16 396/375hp.) and different intakes along with holleys not q-jets as mentioned in above post/s .

The only noteable difference between the 396/325hp & 350hp motors in 69 was the 350hp had an open element air cleaner,larger secondary metering rods,a more agressive hyd cam & better valve springs for higher rpm of 350hp cam,and a different ign timing curve in the distributor but they both had 10:25:1 compression.

The stock 325hp hyd cam had approx 198/198 deg int dur @.05,.398/.398 lift,114 or 115 deg L/S angle which was an extreemly mild cam for a 396. The 350hp cam was called the high lift/high perf hyd cam which had 214/218 deg int dur @.05,.461/.480 lift,115 deg L/S angle which was considerably more cam then the 325hp had but was still a mild cam.


Scott

von
Aug 22nd, 06, 1:45 PM
AZCAMINO & DEAN ARE 100% correct.

FYI,i know for sure the 69 & 70 396/325hp & 350hp motors both had nodular iron cranks from the factory,396/375's had steel cranks.

Its the earlier like 1966-67 396/350hp & 360hp motors that had steel cranks (along with the 396/375hp & 1965 Z16 396/375hp.) and different intakes along with holleys not q-jets as mentioned in above post/s .

The only noteable difference between the 396/325hp & 350hp motors in 69 was the 350hp had an open element air cleaner,larger secondary metering rods,a more agressive hyd cam & better valve springs for higher rpm of 350hp cam,and a different ign timing curve in the distributor but they both had 10:25:1 compression.

The stock 325hp hyd cam had approx 198/198 deg int dur @.05,.398/.398 lift,114 or 115 deg L/S angle which was an extreemly mild cam for a 396. The 350hp cam was called the high lift/high perf hyd cam which had 214/218 deg int dur @.05,.461/.480 lift,115 deg L/S angle which was considerably more cam then the 325hp had but was still a mild cam.


Scott
All the references I have for '69's including the A.M.A. specs I received from Chevrolet as part of the restoration packet, show a forged crank for the 350 hp and cast nodular iron crank for the 325 hp. Before 1968, the 325 hp also had a forged crank.

SWHEATON
Aug 22nd, 06, 2:22 PM
My info comes from GM too but as we all know it's not uncommon to find conflicting info from the general,it happens from time to time.

But i also know this 1st hand from buying my chevelle in 1978 from the original owner when it was new with the #'s matching motor/drivetrain still in the car.

When i pulled the virgin motor (396/350hp)for it's 1st rbld ever it had a nodular iorn crank in it from the factory as i verified from the casting id too even though i could tell just by looking at the casting itself.

The machinest commented on how that nodualr iron crank was a good street unit because it was stronger then a std cast crank but was a little more flexable then a steel crank that was more ridged & prone to cracking if/when flexed.

Scott

68impala
Aug 22nd, 06, 9:34 PM
thanks again for all the info, I looked at the crank (while still in the motor) the only number I can see is 6223. Does that tell us anything?

69ssmike
Aug 22nd, 06, 9:55 PM
I believe that would be a forged crank. Funny, I have a 427 out of a 68 SS Impala in my car now.

Mike Feudo
Aug 22nd, 06, 11:23 PM
6223 is the most common forged crank. I have one that is a cross drilled 427 model but most are the non crossdrilled 396 type. Basically the only real difference between the motors is the cam. The valve springs are heavier and the jetting is different but is really just the cam.

SWHEATON
Aug 23rd, 06, 11:18 AM
According to the AC Delco manuals i have the 396/325hp (7029201 q-jet std trans) & 350hp (7029215 q-jet std trans) motors use the same primary jets & rods (71's/45b rods),the only difference is the secondary metering rds,BC for 325hp & AX for 350hp.

The AX sec rods used in the 350hp motor have a much thinner tip and are richer then the BC rods used in the 325hp motor.

The 25 additional hp in the 350hp motor comes from a combination of a more aggressive cam profile & better valve springs for higher rpm potential,richer sec rods,open element air cleaner,and a different ign timing curve in the dist .

Scott

von
Aug 23rd, 06, 3:30 PM
I just got an ACES Chevelle World magazine today. In it is an article where Chuck Hanson disassembles a numbers matching, 20,000 mile, never rebuilt 396-350 hp JE code engine. It still had the original nylon tooth timing chain and factory fuel pump. In it was a 3856223 forged crank.

my first 68 ss conv
Aug 23rd, 06, 9:31 PM
I am new here, maybe someone can help me. I just purchased a 396. Casting number 3916323, stamped Hi Perf on block, 2 bolt with forged crank #6223, I was thinking this was a1968 Chevelle 396 350 hp motor until I got the engine code, T0913ED which says it is a 325hp? Were there 325hp 396 with Hi Perf stamped in the block? Someone may have replaced the crank. Or do I have a 350hp with wrong engine suffix code? Thanks for any help.

von
Aug 24th, 06, 7:10 AM
Per "Chevy By The Numbers", the ED code was also used in '66 and '67, as well as '68, for 325 hp manual trans 396 Chevelles. The '66 and '67 325 hp engine used a forged crank.

SWHEATON
Aug 24th, 06, 12:33 PM
Von,thanks for info,i was not aware the earlier 396/325hp motors had steel cranks in them which was overkill for that very mild camed low rpm/low power output motor.

Scott