head and cam swap question....
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Joined: Sep 2015
Posts: 56
Likes: 9
From: Orlando, FL
head and cam swap question....
I have a 98 LS1 C5 that I have swapped out some mildly ported 243's and a new Ed Curtis cam(219/223 .625 lift on a 111 lsa) on a stock bottom end. I have also put on new long tube headers and catless mid pipe and SLP loudmouth exhaust. A vararam intake system and a ported LS6 intake and throttle body.
Two questions...
One is, I have bought some red top 30lb injectors for this set up. Do I need these or should I keep the stock ones on?
Two is, do I start this at home and drive it easy to go through a couple of heat cycles for the new dual PAC springs before taking it for the tune and dyno runs. OR do I tow it to a local Vette shop to do the tune before I start it?
Thanks for the input, Chad.
Two questions...
One is, I have bought some red top 30lb injectors for this set up. Do I need these or should I keep the stock ones on?
Two is, do I start this at home and drive it easy to go through a couple of heat cycles for the new dual PAC springs before taking it for the tune and dyno runs. OR do I tow it to a local Vette shop to do the tune before I start it?
Thanks for the input, Chad.
AMP Racing
Joined: Aug 2006
Posts: 10,756
Likes: 589
From: Washington TWP NJ
2023 C5 of the Year Finalist - Modified
2017 C5 of Year Finalist
St. Jude Donor '09-'10-'11-'12
I did something similar. I drove my car (being easy on it) to the tuner on the stock injectors. It will likely run like crap if you change them out beforehand.
I changed the injectors in the parking lot and handed to keys to the tuner and he worked his magic.
I changed the injectors in the parking lot and handed to keys to the tuner and he worked his magic.
Drifting
Joined: Mar 2011
Posts: 1,823
Likes: 43
From: East Aurora NY
#1 - You will most likely need those injectors, but only the tuner on the dyno can see it.
#2 - You can start it at home *with the stock injectors*, do *not* swap injectors and start it. You can even drive it lightly if you don't swap injectors. When you arrive at the tuners, swap them then. Also make sure your tuner has the injector data that they need, all of it, not just 1 table.
#2 - You can start it at home *with the stock injectors*, do *not* swap injectors and start it. You can even drive it lightly if you don't swap injectors. When you arrive at the tuners, swap them then. Also make sure your tuner has the injector data that they need, all of it, not just 1 table.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
I ran a similar cam on my old 98 car---with LT headers and a Fast 78 intake---A 98 has 28 LB injectors larger than most all C5's at only 24---
The industry standard is to not have over 80% duty cycles on your injectors--Mine was over that like 90%--however if your cars use is similar to mine--daily driver occasional street racing or drag racing--It should be just fine---Only time it would not be is it were a track car where you ran it for a long time at WOT-----
Larger injectors do NOT make more HP----Unless you need them--having too large of an injectors than needed will make your start-up--idle--intown drivability suffer----
resulting in dying--surging--etc----
The industry standard is to not have over 80% duty cycles on your injectors--Mine was over that like 90%--however if your cars use is similar to mine--daily driver occasional street racing or drag racing--It should be just fine---Only time it would not be is it were a track car where you ran it for a long time at WOT-----
Larger injectors do NOT make more HP----Unless you need them--having too large of an injectors than needed will make your start-up--idle--intown drivability suffer----
resulting in dying--surging--etc----
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
I have a 98 LS1 C5 that I have swapped out some mildly ported 243's and a new Ed Curtis cam(219/223 .625 lift on a 111 lsa) on a stock bottom end. I have also put on new long tube headers and catless mid pipe and SLP loudmouth exhaust. A vararam intake system and a ported LS6 intake and throttle body.
Two questions...
One is, I have bought some red top 30lb injectors for this set up. Do I need these or should I keep the stock ones on?
Two is, do I start this at home and drive it easy to go through a couple of heat cycles for the new dual PAC springs before taking it for the tune and dyno runs. OR do I tow it to a local Vette shop to do the tune before I start it?
Thanks for the input, Chad.
Two questions...
One is, I have bought some red top 30lb injectors for this set up. Do I need these or should I keep the stock ones on?
Two is, do I start this at home and drive it easy to go through a couple of heat cycles for the new dual PAC springs before taking it for the tune and dyno runs. OR do I tow it to a local Vette shop to do the tune before I start it?
Thanks for the input, Chad.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
#1 - You will most likely need those injectors, but only the tuner on the dyno can see it.
#2 - You can start it at home *with the stock injectors*, do *not* swap injectors and start it. You can even drive it lightly if you don't swap injectors. When you arrive at the tuners, swap them then. Also make sure your tuner has the injector data that they need, all of it, not just 1 table.
#2 - You can start it at home *with the stock injectors*, do *not* swap injectors and start it. You can even drive it lightly if you don't swap injectors. When you arrive at the tuners, swap them then. Also make sure your tuner has the injector data that they need, all of it, not just 1 table.
Do not install them until you are at the tuners.. Good luck on the MOD install.Bill
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