Cathedral or Rectangular Port heads on 6.0
#61
TECH Senior Member
iTrader: (71)
I expect to be making a little bit more next visit with the new converter. I also didn't get to do everything i wanted because of time and money. 460 will be close but Im not sure on this new dyno. All things considered, Im happy with what i made.
As far as normal driving i don't have a problem with the mid range at all, it is very responsive.
Here is my issue.. I have A converter specd for nitrous, which means on motor it isn't keeping me high enough to get away from where these heads dont shine. If i had a 4000, like i planned, this wouldn't be an issue. I didn't have A problem pulling on the 408 cathedral car that makes more hp and tq than me... He was coming back mid range but once we hit third i started pulling again.
If i could get that mid range back with this small converter and keep my top end, id be in serious business. What little these lack in mid range that my converter is showing makes up for top end.
Btw... If you want to point out where i was wrong with the entire money/speed/power thing, Im open to see it.
I still stand everything i have posted.
As far as normal driving i don't have a problem with the mid range at all, it is very responsive.
Here is my issue.. I have A converter specd for nitrous, which means on motor it isn't keeping me high enough to get away from where these heads dont shine. If i had a 4000, like i planned, this wouldn't be an issue. I didn't have A problem pulling on the 408 cathedral car that makes more hp and tq than me... He was coming back mid range but once we hit third i started pulling again.
If i could get that mid range back with this small converter and keep my top end, id be in serious business. What little these lack in mid range that my converter is showing makes up for top end.
Btw... If you want to point out where i was wrong with the entire money/speed/power thing, Im open to see it.
I still stand everything i have posted.
#62
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#64
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I struggled all last year to get my car to leave, tried 4 diff cams, couple converters, changed cam timing on each. Pulled my ls3 scoggin heads off today putn on a set of 799s with a little port work and 3 angle valves. I'll bet anything it picks up on low end. Runs 133 in qtr pump gas full exhaust just useless off start.
#65
Moderator
iTrader: (20)
I expect to be making a little bit more next visit with the new converter. I also didn't get to do everything i wanted because of time and money. 460 will be close but Im not sure on this new dyno. All things considered, Im happy with what i made.
As far as normal driving i don't have a problem with the mid range at all, it is very responsive.
Here is my issue.. I have A converter specd for nitrous, which means on motor it isn't keeping me high enough to get away from where these heads dont shine. If i had a 4000, like i planned, this wouldn't be an issue. I didn't have A problem pulling on the 408 cathedral car that makes more hp and tq than me... He was coming back mid range but once we hit third i started pulling again.
If i could get that mid range back with this small converter and keep my top end, id be in serious business. What little these lack in mid range that my converter is showing makes up for top end.
Btw... If you want to point out where i was wrong with the entire money/speed/power thing, Im open to see it.
I still stand everything i have posted.
As far as normal driving i don't have a problem with the mid range at all, it is very responsive.
Here is my issue.. I have A converter specd for nitrous, which means on motor it isn't keeping me high enough to get away from where these heads dont shine. If i had a 4000, like i planned, this wouldn't be an issue. I didn't have A problem pulling on the 408 cathedral car that makes more hp and tq than me... He was coming back mid range but once we hit third i started pulling again.
If i could get that mid range back with this small converter and keep my top end, id be in serious business. What little these lack in mid range that my converter is showing makes up for top end.
Btw... If you want to point out where i was wrong with the entire money/speed/power thing, Im open to see it.
I still stand everything i have posted.
But hey, if you're happy then that's all that matters. It just won't help to convince others of the "superiority" of the rectangle port heads with numbers like that. Hope you get all those issues fixed.
#66
TECH Senior Member
iTrader: (71)
That was the initial tune after getting it up and running, there is plenty more left in this setup with untouched heads and cam.
Lets not get it all started again.. For the money, they are superior. If you can find me an intake and heads cathedral port that Will perform like these ls3s for the money, im all ears. The 408 ported 243s with fast intake didn't have enough mid range to pull around me then i started pulling on him up top... He makes more power supposedly. The heads cam c5z also didnt have the mid range, him being a 6 speed and 400+# lighter helped him pull in 3rd though.
Lets not get it all started again.. For the money, they are superior. If you can find me an intake and heads cathedral port that Will perform like these ls3s for the money, im all ears. The 408 ported 243s with fast intake didn't have enough mid range to pull around me then i started pulling on him up top... He makes more power supposedly. The heads cam c5z also didnt have the mid range, him being a 6 speed and 400+# lighter helped him pull in 3rd though.
#68
I struggled all last year to get my car to leave, tried 4 diff cams, couple converters, changed cam timing on each. Pulled my ls3 scoggin heads off today putn on a set of 799s with a little port work and 3 angle valves. I'll bet anything it picks up on low end. Runs 133 in qtr pump gas full exhaust just useless off start.
#71
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As I was saying last week switched from scoggin cnced ls3s to 799s and the cathedrals didn't disappoint. On radials pump gas and timing at 29 degrees ramped to 37 at 3800 to 7500 rpm through full exhaust first pass 8th was 6.79 103. It lost 1 mph and gained one tenth over the ls3 head 8th mile. Only got one run in before brake booster went to hell, those 3s are some nice heads but I think there too big for a 6.0.
#73
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Changed nothing, has a 232 243 cam in on both heads and actually took a couple of degrees of time out for the 799s to get it to hook. This is not a perfect comparison because of the radials but will try slicks soon. This motor last year in 8th went 6.55 105 and 10.31 130 qtr on slicks with the 3s. These 799s I lightly ported bowls bought a valve machine and did a 3 angle valve job to the stock 2.00 valves. F that big valve.
#74
Granted you both had Dyno issues, he did come out ahead.
Being an ls1 forum, most people here already have these parts. It would cost more money to switch to ls3 stuff, in most cases.