Running new engine with open shorty headers
09-05-2004, 10:44 AM
#1
Member
Thread Starter
Join Date: Sep 2003
Location: Bucks County Pa
Posts: 183
Likes: 0
Received 0 Likes
on
0 Posts
Car: 85 Firebird
Engine: 355 Vortec TPI
Transmission: 700r4 with Pro-Built goodies
Axle/Gears: LS1 3.42 Posi Disc
Running new engine with open shorty headers
I was told that if i ran my new engine with my open shorty headers that i could cause valve damage. Why is this is it even true? Does it maybe have something to do with back pressure and the valves being heated up then cooled so rapidly? Basically what i wanted to know was could i run the eng in the driveway to set timing and tune the carb without hooking up my PITA exhaust. Any help/insight would be greatly appreciated. Thanks -Bob
09-05-2004, 11:15 AM
#2
Supreme Member
Join Date: Dec 2001
Location: boonton, NJ
Posts: 1,854
Likes: 0
Received 0 Likes
on
0 Posts
Car: 84 camaro Z28
Engine: 434sbc
Transmission: powerglide
Axle/Gears: moser 9" with 411 posi
when i first broke in my 400 i ran it with just the headers and a y-pipe. i never had any problems with it. i would imagine that you would warp a valve with just the shorties and nothing else
09-05-2004, 12:37 PM
#3
Member
Join Date: Aug 2002
Location: Canada
Posts: 223
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Firebird
Engine: 350, 416's, 230/230 cam, torkerII, q-jet
Transmission: T5
It's an old wives tale. How many times have people run with open headers and warped/cracked a valve? None.
09-05-2004, 01:49 PM
#4
Supreme Member
Join Date: Nov 2003
Location: Philly
Posts: 1,965
Likes: 0
Received 0 Likes
on
0 Posts
Car: 85 firebird
Engine: Pos 2.8 pulled and replaced with a 350 tpi motor converted to carb.
Transmission: 700r4, vette servo,shift kit, hayden 15"x8" trans cooler.
When we got my motor together and finished , and after I got back from the hospital (starter fell on my pinky finger and smashed it, 6 stiches) We ran the motor with no exhaust.
09-05-2004, 03:22 PM
#5
Senior Member
Join Date: Apr 2000
Location: Alberta, Canada
Posts: 860
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1987 IROC
Engine: Vortec 350 TPI
Transmission: 7004r
When I put my motor into my green car I ran it open headered to the muffler shop. damaging valves is not a concern with open headers. when I race I have a cutout that opens right after the ypipe.. basically open headers. no problems with valve damage after 3 years of racing.
Thread
Thread Starter
Forum
Replies
Last Post
theshackle
Tech / General Engine
4
03-05-2017 06:37 PM
