Reason for switching to a carb intake??
#63
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I kinda viewed running 90mm stuff whether it be the FAST stuff, carb or the LS2 intake (which is what I am running), as all having potentially the same power levels. I wonder if the big does run the carb intake for better fuel distribution or the fact you could run a 105mm TB and then I'd think you'd see some bigger numbers. What are the 7 second guys doing for TB's?
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wouldn't the 105mm TB be less or a restriction compared to a 78mm or a 90mm? Less retriction is more cfm at the same boost pressure so i figured i would do well to upgrade to a larger TB and decrease the restriction in the intake tract.
I dunno, im still a rookie at this...![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
I have been trying to find a few articles i read where a ls1/ls6 was retrofitted with a carb manifold. The ones i have found have all been with carbs on them so its not necessarily apples to apples.... however, the general readings is that the ls6 manifold out performanced the card-equipped carb manifold through the powerband.
Interesting results but still not enough to steer me away from one....
http://www.superchevy.com/technical/...s/0409sc_gmpp/
I dunno, im still a rookie at this...
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
I have been trying to find a few articles i read where a ls1/ls6 was retrofitted with a carb manifold. The ones i have found have all been with carbs on them so its not necessarily apples to apples.... however, the general readings is that the ls6 manifold out performanced the card-equipped carb manifold through the powerband.
Interesting results but still not enough to steer me away from one....
http://www.superchevy.com/technical/...s/0409sc_gmpp/
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Originally Posted by kp
Independant thought, imagine that ![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
Sometimes its easy to overanalyze purchases and decisions, especially expensive ones. With race cars there is usually more then one 'correct' way to achieve a goal, if you simply just like the way it looks or if you think it will work for you just use it and why worry what other people have to think. In the big picture its a small part of the overall combination.
![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
Sometimes its easy to overanalyze purchases and decisions, especially expensive ones. With race cars there is usually more then one 'correct' way to achieve a goal, if you simply just like the way it looks or if you think it will work for you just use it and why worry what other people have to think. In the big picture its a small part of the overall combination.
![Grin](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_grin.gif)
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
Ive always had the theory that people that always seem to excel in racing and "make it look easy," do so because they have the means and attitude to "find answers" instead of just "asking questions"
If that makes any sense.
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Well, i have done it.... i have actually used the search button!! that felt weird.
Anyways, i found a chart with some flow numbers... its still not 100% conclusive but its something.
laterZ!
https://ls1tech.com/forums/showpost....9&postcount=48
thanks JRP for fixing the search button!!!!
Anyways, i found a chart with some flow numbers... its still not 100% conclusive but its something.
laterZ!
https://ls1tech.com/forums/showpost....9&postcount=48
thanks JRP for fixing the search button!!!!
#67
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Originally Posted by obZidian
wouldn't the 105mm TB be less or a restriction compared to a 78mm or a 90mm? Less retriction is more cfm at the same boost pressure so i figured i would do well to upgrade to a larger TB and decrease the restriction in the intake tract.
As I say, most IC pipework is 3"/76mm OD.
I didnt bother calculating, but I'm sure my 85mm TB, has a greater surface area, than my 3" pipework ( assuming its all straight too, as bends do reduce flow )
I would say that my 75mm TB ( or whatever size stock is ) didnt pose a restriction, and I would be 100% confident that my 85mm TB poses no restriction whatseover at my power level, and that going larger would only result on poorer drivability, and be pretty much pointless.
As for the carb intake. Whilst I did it primarily for visual appeal, I really did hope that I would have seen substantial gains, based on my readings here. ( say 50rwhp )
I honestly dont believe that has happened, certainly not above 5000rpm.
SOTP and fuel requirements, tell me, that I may have made mid-range gains, but still not huge ones.
Perhaps there is a head/cam issue here. Compared to the faster runners, my cam and head combo is defo on the conservative side.
But I dont think for one second, that me head, is limiting the intake flow after the intake swap.
That reasoning makes no sense to me.
If anything, I had hoped the better intake, would allow my smaller heads, to perform better.
But as I say, I havent gone slower, and I like how it looks. So its staying where it is regardless.
Heads are an area where I could be tempted though....
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understandeable...
but wouldn't the larger TB also make you look tougher?! I mean, that is the only thing that im concerned about really...
come on, who wants a silly, little 90 milla-mita tb when you can get a 105 milla-meta and not look like a girl?
"Arrg get down!!!"
but wouldn't the larger TB also make you look tougher?! I mean, that is the only thing that im concerned about really...
come on, who wants a silly, little 90 milla-mita tb when you can get a 105 milla-meta and not look like a girl?
"Arrg get down!!!"
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Originally Posted by kp
Besides the intake in your sig sure LOOKS good ![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
IMO I dont think you made a bad decision on doing that intake, obviously you are doing a fairly high dollar build and since most of the faster cars out there are using them it makes perfect sense to use one. Like I said earlier on a F1 engine I dont think the intake is going to make or break the combination.
![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
IMO I dont think you made a bad decision on doing that intake, obviously you are doing a fairly high dollar build and since most of the faster cars out there are using them it makes perfect sense to use one. Like I said earlier on a F1 engine I dont think the intake is going to make or break the combination.
HELL YEH, I CANT STOP LOOKING AT THAT BEAUTY!@!
DAMN, looking at this LS2 intake and ls7 intake i dont know why i never went with carb.... bump, ls7 intake for sale... lol. JK
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Originally Posted by LS2Camaro
But this is sooo much more fun, and Im learning alot. Thanks guys.
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Keith is that shop doing your build located in lauderdale? If so my buddy is having either a Warhawk or resleeved ls7 block done at that place. you'll have to bring that car up to orlando when its done!
#76
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Originally Posted by onfire
kp, here's some stats that have bothered me for a while.
LPE 345ci TT gains nothing (per LPE) with a FAST 90 over a LS6 at 16-18 psi.
LPE 427 TT gains 30-40rwhp (per LPE) with a FAST 90 over a LS6 at 16-18 psi with the same GT2871R turbos.
Comments?
LPE 345ci TT gains nothing (per LPE) with a FAST 90 over a LS6 at 16-18 psi.
LPE 427 TT gains 30-40rwhp (per LPE) with a FAST 90 over a LS6 at 16-18 psi with the same GT2871R turbos.
Comments?
now when it comes to the intake, the intake can only allow as much air in as the motor can take(427 can take more air easier than a 345). so a 345 not being able to consume as much as a 427 would not benefit from a larger intake when boost is involved. the motor is already taking in as much as it can 16-18psi, so intake will not affect it when under boost.
now a 427 which naturally needs and can consume more air would benefit from the less restrictive intake and would also make more power with the same amount of boost as the smaller engine. think of it as 18 psi thru a straw and then 18 psi thru a hose. yes psi is psi but when it comes to the volume something can flow then it takes more air to create 18psi in a hose than it does in a straw.
i may be wrong with all this or just partially wrong so if anyone can correct me or clearify what im trying to say thatd be great. otherwise this is how i see it working out
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Last edited by C Murda; 11-19-2006 at 03:29 PM.
#77
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Originally Posted by C Murda
didnt read on to see if anyone replied to this but i believe why this happened is because with better flowing capabilities (being a larger displacement motor in this case) 18psi is equivalent to 22-24 psi (in a smaller displacement motor)
now when it comes to the intake, the intake can only allow as much air in as the motor can take(427 can take more air easier than a 345). so a 345 not being able to consume as much as a 427 would not benefit from a larger intake when boost is involved. the motor is already taking in as much as it can 16-18psi, so intake will not affect it when under boost.
now a 427 which naturally needs and can consume more air would benefit from the less restrictive intake and would also make more power with the same amount of boost as the smaller engine. think of it as 18 psi thru a straw and then 18 psi thru a hose. yes psi is psi but when it comes to the volume something can flow then it takes more air to create 18psi in a hose than it does in a straw.
i may be wrong with all this or just partially wrong so if anyone can correct me or clearify what im trying to say thatd be great. otherwise this is how i see it working out![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
now when it comes to the intake, the intake can only allow as much air in as the motor can take(427 can take more air easier than a 345). so a 345 not being able to consume as much as a 427 would not benefit from a larger intake when boost is involved. the motor is already taking in as much as it can 16-18psi, so intake will not affect it when under boost.
now a 427 which naturally needs and can consume more air would benefit from the less restrictive intake and would also make more power with the same amount of boost as the smaller engine. think of it as 18 psi thru a straw and then 18 psi thru a hose. yes psi is psi but when it comes to the volume something can flow then it takes more air to create 18psi in a hose than it does in a straw.
i may be wrong with all this or just partially wrong so if anyone can correct me or clearify what im trying to say thatd be great. otherwise this is how i see it working out
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
#78
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i would think if your forcing more air in than the motor can consume it would fill the intake evenly , but if no one agrees with that look how sharp the bend is on the elbows made to clear the factory hoods it would lean out the front cylinders because of such a sharp bend all the air is going to the rear i have a factory ls6 intake and made 1030 hp at 17# and 1162 hp at 23#.
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that elbow isnt crucial to the flow pattern of the FI, most elbows arent a straight 90.
It would be interesting to see if your power lvl would stay the same but the psi drop if you switched to a carb intake.
Great numbers
do you have a dyno graph to show the curve that you could post?
It would be interesting to see if your power lvl would stay the same but the psi drop if you switched to a carb intake.
Great numbers
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#80
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Originally Posted by STP
i would think if your forcing more air in than the motor can consume it would fill the intake evenly , but if no one agrees with that look how sharp the bend is on the elbows made to clear the factory hoods it would lean out the front cylinders because of such a sharp bend all the air is going to the rear i have a factory ls6 intake and made 1030 hp at 17# and 1162 hp at 23#.
The same amount of fuel gets injceted, regardless of where the air actually goes.