Which headers? - ZR-1 Net Registry Forums

Schrade · 05-09-2013

While the car is at the 'speed' shop, I'm pondering headers, since I'll be 'hands on' as repairs are effected here.

Which brand are the easiest install? As in 'drop in'?

I don't keep the hammer on the floor - mostly light pedal. Which brand is suggested here?

Only other thing to consider is some modest intake work in the near future - porting most likely, and perhaps putting a can opener to the K&N box up front there...

And I've asked this before here, but missed responses if they were posted; what are the airflow bottelnecks in a '90 LT5? Intake? Exhaust? No mods now, except Marc's memory / calibration module in the ECM..............................

What brand do you have in yours?

Dynomite · 05-09-2013

Quote:

Originally Posted by Schrade

What brand do you have in yours?

Stainless Works on 91' and 92'

SW Group Buy

SW headers ZR1CORVOR
SW exhaust ZR1CHAMSW

Installing Headers
Installing Engine In ZR1

Quote:

Originally Posted by Schrade

perhaps putting a can opener to the K&N box up front there...

Stainless Steel Air Box and Air Filter (L98 and LT5)

Paul Workman · 05-09-2013

The 90 LT5 has the most to gain from porting the top end. The primary runners are 33mm compared to 34.5 (about) for the later 93s and up. Also, the primary injectors are sealed at the top of the injector instead of at the bottom. This allows you to remove ALL of the shroud on the primary side injectors -making the 90 IH thee ideal year for top end porting.

The starting point for most top end porting is approx. 36mm. There are nuances that improve over that (but Pete n Marc each have dibbs on one of my family jewels, should I divulge a sacred FBI secret

)

As far as port matching into the heads, I believe there is merit to tapering the port all the way down to the valve guide. But, there is some real concern for "punching through" if you don't have a road map, and pulling the head(s) means pulling the motor...not a cheap or easy thing to do.

P.

Corbusa · 05-09-2013

I have new OBX headers waiting for my lazy AZZ to install. I have wondered if the SW are better ? I have heard that the OBX needs to be dimpled near the steering box. If the group buy got the SW headers cheap enough I'd probably go that route and sell my OBX ( just thinking out loud.) Not to change the thread but also since the OBX need to be dimpled I wish someone could show where and how much . This way I wouldnt have to install twice.
Dude here locally that has a ceramic shop will coat the headers for $175.00..
Good question and timing Schrade. thanks

sammy · 05-09-2013

i like corey hendersons headers alot better than the stainless works which i took off my 92 to put coreys on .they are a copy of the jeal headers which i have on my 90 .

boostedmaxPSI · 05-09-2013

I have SW coated which Corey installed and tuned. If I could do it all over again I would go with Corey and support a local vendor. I was impatient.

Fully Vetted · 05-09-2013

Really? Not happy with them or is the extra cost not worth it?

efnfast · 05-09-2013

I wrote myself a big note. "Buy Coreys headers". Then the dollars signs took over and went with OBX. Hope this wasn't a really big mistake.

FU · 05-09-2013

No need too dimple the header's.

When there is a need to dimple the header's. The engine/trans need to be centered properly in the car.

And if I need another set of header's I'd get them from Corey , why ? Because he's Corey and he builds superior.

boostedmaxPSI · 05-09-2013

Quote:

Originally Posted by Fully Vetted

Really? Not happy with them or is the extra cost not worth it?

100% satisfied. Very good product. Would have preferred to support a local vendor. Plus Corey is just a great guy. I don't know anyone at SW.

05-09-2013	#1
Schrade Join Date: Dec 2012 Location: NC Posts: 1,783	Which headers? While the car is at the 'speed' shop, I'm pondering headers, since I'll be 'hands on' as repairs are effected here. Which brand are the easiest install? As in 'drop in'? I don't keep the hammer on the floor - mostly light pedal. Which brand is suggested here? Only other thing to consider is some modest intake work in the near future - porting most likely, and perhaps putting a can opener to the K&N box up front there... And I've asked this before here, but missed responses if they were posted; what are the airflow bottelnecks in a '90 LT5? Intake? Exhaust? No mods now, except Marc's memory / calibration module in the ECM.............................. What brand do you have in yours?

05-09-2013	#3
Paul Workman Join Date: Nov 2007 Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri Posts: 6,466	Re: Which headers? The 90 LT5 has the most to gain from porting the top end. The primary runners are 33mm compared to 34.5 (about) for the later 93s and up. Also, the primary injectors are sealed at the top of the injector instead of at the bottom. This allows you to remove ALL of the shroud on the primary side injectors -making the 90 IH thee ideal year for top end porting. The starting point for most top end porting is approx. 36mm. There are nuances that improve over that (but Pete n Marc each have dibbs on one of my family jewels, should I divulge a sacred FBI secret) As far as port matching into the heads, I believe there is merit to tapering the port all the way down to the valve guide. But, there is some real concern for "punching through" if you don't have a road map, and pulling the head(s) means pulling the motor...not a cheap or easy thing to do. P.

05-09-2013	#4
Corbusa Join Date: Sep 2011 Location: TN Posts: 577	Re: Which headers? I have new OBX headers waiting for my lazy AZZ to install. I have wondered if the SW are better ? I have heard that the OBX needs to be dimpled near the steering box. If the group buy got the SW headers cheap enough I'd probably go that route and sell my OBX ( just thinking out loud.) Not to change the thread but also since the OBX need to be dimpled I wish someone could show where and how much . This way I wouldnt have to install twice. Dude here locally that has a ceramic shop will coat the headers for $175.00.. Good question and timing Schrade. thanks

05-09-2013	#5
sammy Join Date: Jun 2010 Location: Lone Pine, CA Posts: 580	Re: Which headers? i like corey hendersons headers alot better than the stainless works which i took off my 92 to put coreys on .they are a copy of the jeal headers which i have on my 90 .

05-09-2013	#6
boostedmaxPSI Join Date: Apr 2012 Location: TEXAS Posts: 171	Re: Which headers? I have SW coated which Corey installed and tuned. If I could do it all over again I would go with Corey and support a local vendor. I was impatient.

05-09-2013	#7
Fully Vetted Join Date: Sep 2012 Location: Rockwall, Tx Posts: 1,504	Re: Which headers? Really? Not happy with them or is the extra cost not worth it? __________________ _________________ 1994 AB/Grey #141 430 RWHP/392 RWTQ FBI Lyposuction / Secondaries relieved of duty / SW Long Tube Headers / Corsa Exhaust / FIC SS Injectors / MSD Coils / Lightweight Pulleys / Corey tuned B & M Shifter / Aluminum Flywheel / Samco Hoses / Shelby Series One's / C4 No Flex Frame Stiffener BBC - Bling By Carter: Custom ZR-1 Center Caps / Custom Plenum Plate / Air Box Knobs / TB Cover / Oil Filter Cover

05-09-2013	#8
efnfast Join Date: Nov 2011 Location: Dunbarton NH Posts: 7,555	Re: Which headers? I wrote myself a big note. "Buy Coreys headers". Then the dollars signs took over and went with OBX. Hope this wasn't a really big mistake.

05-09-2013	#9
FU Join Date: Mar 2004 Location: Found Member Posts: 4,327	Re: Which headers? No need too dimple the header's. When there is a need to dimple the header's. The engine/trans need to be centered properly in the car. And if I need another set of header's I'd get them from Corey , why ? Because he's Corey and he builds superior. Last edited by FU; 05-09-2013 at 07:50 PM.