12.90 on stock l98 heads
07-09-2005, 11:48 AM
#1
Member
Thread Starter
iTrader: (6)
Join Date: Jan 2003
Location: indiana
Posts: 255
Likes: 0
Received 1 Like
on
1 Post
Car: 91 Z-28
Engine: 420 sbc
Transmission: T56
Axle/Gears: 12 bolt/4.10 gears
12.90 on stock l98 heads
Went to Muncie dragway last night and ran a new best. 12.90 at 106 mph still on the stock 91 l98 heads. I don't think I can go any faster on the stock heads, but that mph means they will make decent power. My car is about 3500 lbs too so the stock heads must be good for at least 350 horsepower.
07-10-2005, 02:33 PM
#3
Member
Thread Starter
iTrader: (6)
Join Date: Jan 2003
Location: indiana
Posts: 255
Likes: 0
Received 1 Like
on
1 Post
Car: 91 Z-28
Engine: 420 sbc
Transmission: T56
Axle/Gears: 12 bolt/4.10 gears
I am running a 91 l98. The shortblock is stock besides the cam. The heads are stock except for valvesprings for the cam. Still using the stock rocker arms too. The heads have never been off the block either.
07-11-2005, 05:50 PM
#6
Supreme Member
iTrader: (1)
Join Date: Mar 2001
Location: Chesterfield, Indiana
Posts: 4,226
Likes: 0
Received 5 Likes
on
4 Posts
Car: 1991 Z28 Camaro
Engine: 5.7
Transmission: Jasper 700R4 Stage II
Axle/Gears: 3.23 For Now
that's awesome man, wish I could have made it up to Muncie, let me know next time you go so I can make it up there 
Trending Topics
07-15-2005, 01:48 PM
#9
Supreme Member
Join Date: Jul 1999
Location: Ahead of you...
Posts: 2,752
Likes: 0
Received 6 Likes
on
5 Posts
Car: 1984 LG4 Camaro
Engine: 350 Roller Motor
Transmission: Level 10 700R4
Axle/Gears: Strange 12 bolt 3.42
Actually its putting out about 325hp, which is awesome with stock heads.
07-15-2005, 04:35 PM
#10
Member
Thread Starter
iTrader: (6)
Join Date: Jan 2003
Location: indiana
Posts: 255
Likes: 0
Received 1 Like
on
1 Post
Car: 91 Z-28
Engine: 420 sbc
Transmission: T56
Axle/Gears: 12 bolt/4.10 gears
When I posted 350 horsepower I should have specified flywheel. It actually should be making 320 or so at the wheels and 370 at the crank. That is definitely awesome with stock heads.
Here is my setup:
Engine: 91 l98 350 with miniram and zz-409 cam
Trans: 700r4 with vigilante 3200 stall
gears: 3.73
exhaust: edelbrock shorties and y pipe (crap), cutout where the cat converter should be, and flowmaster american thunder catback.
Suspension: random tech torque arm with pinion angle set at -2º, spohn control arm relocation brackets, spohn lower control arms (poly bushed), spohn panhard bar. kenny brown subframes (a must have), hotchkis 1 7-16" front and 1" rear swaybars (both are on the car at all times), and Eibach pro kit.
Tires: bfg drag radials
Here is my setup:
Engine: 91 l98 350 with miniram and zz-409 cam
Trans: 700r4 with vigilante 3200 stall
gears: 3.73
exhaust: edelbrock shorties and y pipe (crap), cutout where the cat converter should be, and flowmaster american thunder catback.
Suspension: random tech torque arm with pinion angle set at -2º, spohn control arm relocation brackets, spohn lower control arms (poly bushed), spohn panhard bar. kenny brown subframes (a must have), hotchkis 1 7-16" front and 1" rear swaybars (both are on the car at all times), and Eibach pro kit.
Tires: bfg drag radials
07-17-2005, 07:28 PM
#12
TGO Supporter
Join Date: Dec 2001
Location: ELIZABETH,PA,USA
Posts: 2,308
Likes: 0
Received 0 Likes
on
0 Posts
Great times on those heads!
With that MPH you could even get to about 12.7/8's
Corral HP calculator has you at about 332 HP at the flywheel.
Very impressive
With that MPH you could even get to about 12.7/8's
Corral HP calculator has you at about 332 HP at the flywheel.
Very impressive
07-18-2005, 08:02 AM
#13
Just think if you installed bigger undercut valves and done some P&P work on those heads.
You dont have any coil bind with the springs and the stock heads with that zz-409 cam? .520 lift?
What about screw in studs? still press in?
You dont have any coil bind with the springs and the stock heads with that zz-409 cam? .520 lift?
What about screw in studs? still press in?
Last edited by bluegrassz; 07-18-2005 at 08:15 AM.
07-18-2005, 09:13 AM
#14
Member
Thread Starter
iTrader: (6)
Join Date: Jan 2003
Location: indiana
Posts: 255
Likes: 0
Received 1 Like
on
1 Post
Car: 91 Z-28
Engine: 420 sbc
Transmission: T56
Axle/Gears: 12 bolt/4.10 gears
I'm not even going to mess with the stock heads. In a couple months I'm going for some CNC ported afr 190s. I was told I'll see bottom 12s and maybe high 11s when I swap the heads. As far as those springs, I've still got a good .030 at max lift before coil bind, and the studs are the stock pressed in pieces.
07-18-2005, 01:42 PM
#15
Originally posted by 92RSZ
I'm not even going to mess with the stock heads. In a couple months I'm going for some CNC ported afr 190s. I was told I'll see bottom 12s and maybe high 11s when I swap the heads. As far as those springs, I've still got a good .030 at max lift before coil bind, and the studs are the stock pressed in pieces.
I'm not even going to mess with the stock heads. In a couple months I'm going for some CNC ported afr 190s. I was told I'll see bottom 12s and maybe high 11s when I swap the heads. As far as those springs, I've still got a good .030 at max lift before coil bind, and the studs are the stock pressed in pieces.
good luck and great times.
07-19-2005, 10:35 PM
#17
Supreme Member
Join Date: Jul 1999
Location: Saskatoon, Saskatchewan, Canada
Posts: 1,011
Likes: 0
Received 0 Likes
on
0 Posts
Car: 86 Trans Am
Engine: 406
Transmission: TH350, 4200
Axle/Gears: Moser 9", 3.89
Originally posted by 92RSZ
I'm not even going to mess with the stock heads. In a couple months I'm going for some CNC ported afr 190s. I was told I'll see bottom 12s and maybe high 11s when I swap the heads. As far as those springs, I've still got a good .030 at max lift before coil bind, and the studs are the stock pressed in pieces.
I'm not even going to mess with the stock heads. In a couple months I'm going for some CNC ported afr 190s. I was told I'll see bottom 12s and maybe high 11s when I swap the heads. As far as those springs, I've still got a good .030 at max lift before coil bind, and the studs are the stock pressed in pieces.
(Unless of course you already found some in someone's inventory.)
07-22-2005, 09:35 AM
#18
Member
Join Date: May 2004
Location: plainfield, il
Posts: 452
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 gta
Engine: L98
Transmission: 700r4
just saw this thread. 1st congrats on the 12.90 pass
i'm on the everquest
for a 12.9x pass on stock cam, heads and internals. Right now with mods from last winter running time in sig. I think with a good stall converter, gears and a well done dyno tune i should be able to get there
i'm on the everquest
for a 12.9x pass on stock cam, heads and internals. Right now with mods from last winter running time in sig. I think with a good stall converter, gears and a well done dyno tune i should be able to get there 
Thread
Thread Starter
Forum
Replies
Last Post
theshackle
Tech / General Engine
4
03-05-2017 06:37 PM
