853 vs 243 heads
TECH Fanatic
Joined: Nov 2001
Posts: 1,027
Likes: 2
From: KS
The 2.73's are not holding you back. A good friend of mine has CHS portef heads (806 castings '98) a 224/224 Comp cam all the bolt ons ls6 intake. He has 2.73 gears Yank converter and runs 11.40's all day. Several guys in our circle same heads/cam size same results. Low 11's high 10's. It takes more cam for 10's but its doable. And im talking about stock bottom ends pump gas pass seat and back seats removed only.
Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
The 2.73's are not holding you back. A good friend of mine has CHS portef heads (806 castings '98) a 224/224 Comp cam all the bolt ons ls6 intake. He has 2.73 gears Yank converter and runs 11.40's all day. Several guys in our circle same heads/cam size same results. Low 11's high 10's. It takes more cam for 10's but its doable. And im talking about stock bottom ends pump gas pass seat and back seats removed only.
TECH Fanatic
Joined: Nov 2001
Posts: 1,027
Likes: 2
From: KS
It was 118 mph. I know on a 75 shot of NO2 he ran a 10.9x at 125 or 126. Pretty sure the 60' times were high 1.5 or low 1.6's. We had another friend with a '98 SS 226/228 cam same converter but 4.10 gears it ran 11.20's. That guy always gave the guy with 2.73 gears hell for not changing them but he said why? The 2.73 geared car dynoed 425 rwhp. Both of these cars I mentioned were '98's and had ported '98 (perimeter bolt) heads.
What converter? What tire? One of those 2 things in your combo SUCKS hard.
Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
Yank SS3800 and Nitto 555R. Before anyone says anything about the Nittos, I did hit a 1.7 60' with the Nittos before the headers and cam. Once the cam and headers were done, I did not spin out of the whole when I came off the line. The car was very lazy, 12.5 @113 with a 2.4 60' at Atco in NJ. Doing the 1/4 in 1st and 2nd gear doesn't help either. Car doesn't hit 3rd till I'm a few feet from the traps which is why I said that the 2.73s are holding me back.
Sounds like something is up. There is no good reason listed here that a cammed ls1 car with a 3800 converter should be bogging to a 2.4 60ft. I wouldn't point fingers entirely at the gears for it either unless you are running a 29" tall tire or something crazy.
Has the car been properly tuned? Are you sure it isn't missing (could have damaged a plug or wire during install)? How does the transmission fluid smell/look?
Has the car been properly tuned? Are you sure it isn't missing (could have damaged a plug or wire during install)? How does the transmission fluid smell/look?
Yes 853s are the worst head out of all the stockers,243s will be a nice upgrade, but i would take some worked 853s over stock 243s any day, i would at least send them out for a lil port work, it will be well worth the extra cash, or if your on a budget 243s are still going to make a nice gain
Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
Sounds like something is up. There is no good reason listed here that a cammed ls1 car with a 3800 converter should be bogging to a 2.4 60ft. I wouldn't point fingers entirely at the gears for it either unless you are running a 29" tall tire or something crazy.
Has the car been properly tuned? Are you sure it isn't missing (could have damaged a plug or wire during install)? How does the transmission fluid smell/look?
Has the car been properly tuned? Are you sure it isn't missing (could have damaged a plug or wire during install)? How does the transmission fluid smell/look?
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
This is how the car was with just nittos, the SS3800 converter and the SLP Loudmouth. 12.2 @ 109mph 1.7 60' with only 313 rwhp.
http://youtu.be/G_FVfZlGVmM
This video is before the cam and header setup got re-tuned, it ran 12.5 @ 113 with a 2.4 60' at Atco in July.
http://www.myspace.com/video/roarin-...ne-run/2633897
This video is after the re-tune at Orlando speed world in October. It ran 13.0 @ 110 with the red light (clocks started running and spinning terribly off the line since I couldn't get a proper burnout because of the front brakes at the time) don't remember the 60'. Listen to when the car hits 3rd and then look how close I am to the traps.
http://youtu.be/TVtgoue0fD4
http://youtu.be/G_FVfZlGVmM
This video is before the cam and header setup got re-tuned, it ran 12.5 @ 113 with a 2.4 60' at Atco in July.
http://www.myspace.com/video/roarin-...ne-run/2633897
This video is after the re-tune at Orlando speed world in October. It ran 13.0 @ 110 with the red light (clocks started running and spinning terribly off the line since I couldn't get a proper burnout because of the front brakes at the time) don't remember the 60'. Listen to when the car hits 3rd and then look how close I am to the traps.
http://youtu.be/TVtgoue0fD4
Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
Here's another good vid to show when the car hits 3rd, around 101-103mph
http://youtu.be/GLrBc2ALbC0
http://youtu.be/GLrBc2ALbC0
Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
Should have updated this awhile ago. Got everything fixed https://ls1tech.com/forums/generatio...-breakage.html and have to take some metal off the frame since now the passenger side header is hitting. Was thinking to just say F it and go with a tubular K member from BMR. In the meantime, with these heads, 10% UD pulley and "LS1 Intake" (I know, I know) how much of a gain do you guys think I've picked up? I'll include my old dyno sheet, when the cam and headers were first installed back in 2005, when I get home today.
New to the forum dont wanna start a new thread since have a question about the 243 heads dont mean to hijack the thread either op. I have a 98
z28 read that they have the perimeter valve covers that being said 243 have center bolt valve and head bolts. What else would i need to do the swap to center bolt heads. Thanks
z28 read that they have the perimeter valve covers that being said 243 have center bolt valve and head bolts. What else would i need to do the swap to center bolt heads. Thanks
Thread Starter
Joined: Aug 2002
Posts: 4,578
Likes: 49
From: Kissimmee, FL
Ok here is the dyno sheet. This was after the headers and cam were done back in 2006. Tuner said that with that cam, I was making 20hp less than what he usually saw with it. He did blame the lifters back then.
Now, cam is the same to replace the one that got damaged but car now has 10% UP and the 243 heads untouched. Any guesses to what the rwhp would be now?
Now, cam is the same to replace the one that got damaged but car now has 10% UP and the 243 heads untouched. Any guesses to what the rwhp would be now?
Last edited by Roarin_8; Aug 17, 2013 at 08:05 PM.
TECH Fanatic
Joined: Nov 2001
Posts: 1,027
Likes: 2
From: KS
Ignorance runs wild on this board. See my earlier post where a friend of mine runs 11.40's with 224/224 cam and 2.73 gears. Those are 806 heads. It kills me so many still struggle to run mid to low 11's. All the 806, 853, 241 heads flow the SAME ported! The 243 ported flows more at .600" lift and up. They do not flow more below that. So your .600" lift cam benefits little from a few cfm the one time the valve sees .600" and the valve sees everything below that twice.
From what I've read, Cams usually spend a good amount of their time at high lift, depending on a lobe. More time than they spend at mid life if I'm not mistaken, doesn't matter that they see those lifts twice. But your point is still valid.
Last edited by DREAMZ28; Jan 28, 2014 at 06:52 PM.
