Best way to choke a 408 N/A..... unported GMPP L92 Intake FTL!
05-02-2008, 09:45 PM
#61
I understand people can't accept the truth.
05-03-2008, 07:05 PM
#62
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Also, can I get a buddy that makes intercooler piping for Supras and can aluminum weld make me a hat and piping to hook my maf to until I can get a SD tune?
Who sells the accufab for a decent price?
from the site:
For those of you wishing to switch from a carburetor intake to electronic fuel injection (EFI), Accufab has developed two high flow throttle bodies to meet your needs. The Accufab 4150 and 4500 are made from the finest billet aluminum, polished to a mirror finish or available anodized black blue or red. The Accufab 4150 flows 1215 CFM and has four 1-3/4" brass throttle plates. The Accufab 4500 flows 2128 CFM and has four 2-1/4" brass throttle plates. Both styles have high quality progressive linkage and use late model GM electronics, included.
Part #IAC4B is available polished, red, blue or black anodized and includes o-rings and mounting hardware.
05-05-2008, 11:05 AM
#66
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I can't see that big *** elbow being a restriction but I can see where the elbow is like extending all of the runner lengths, and maybe that is where the problem is. I wonder if the problem would exist if the TB was mounted on the intake directly, with an elbow on top of it. Then obvioulsy clearance would be an issue, but what if you were to use a 4barrel tb with a cobra elbow on it or a tight radius elbow for clearence would those not introduce restriction also if the restriction is infact the elbow itself? I guess we need to find out exactly why this intake is not flowing, be it the elbow itself or the simple fact that adding an elbow between the TB and the intake is like extending all of the runners... I'm leaning towards the latter.
05-05-2008, 11:29 AM
#67
You read that correct as well. The guys I deal with know this as well. They've tested with several Pro Stock guys to see what they could find. They are all for new things and believe it or not, FI is not the route any of them are wanting to go or willing to go.
I understand people can't accept the truth.
I understand people can't accept the truth.
EFI is great, I love it. But it doesnt make more power just cause its EFI.
05-05-2008, 11:34 AM
#68
Finally someone that understands a little more then just the obvious.
05-06-2008, 03:50 PM
#69
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Ok so everybody agree's that the elbow doesnt make as much power as some other options. But it should still make more power than an l76 intake right. I mean I will take a 20 hp loss if it means big gains on the spray. My combo has this same set-up and I will be getting tuned here real soon. And then some track times. I have a mail order tune from PCM for less in it now and I took the car down the road one time and it feels pretty mean.My car also has a patric G cam in it.There is more wrong with Wize ***'s car than the intake. I can bet when it is all said and done he is going to find an issue either in the tunning or something wrong with the motor itself. Here is what a healthy 408 sounds like.
http://www.youtube.com/watch?v=P6oUKlbJhoo
http://www.youtube.com/watch?v=P6oUKlbJhoo
05-07-2008, 09:26 AM
#71
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The elbow is not a restriction, it's ruining the airflow and airstream. It's too short and has too quick of a short turn. The air moving across the short turn of the elbow has to turn 180* in such a short distance to get to #1 and #2 port that it's killing power in those two cylinder alone, and probably hurting #3 & 4 as well. Moving air (airflow), just like your car, cannot turn on a dime. It has inertia and has to have ample time/space to turn. As the volume of air goes up, the more time/space (longer s/t) it requires.
He needs to check his plugs, and he'll see that the front plugs are black and the rear plugs are considerably cleaner.
If the elbow was reconfigured to offer a longer short turn, or better yet, a straight section, this would not be a problem. If the engine was FI it would probably not be as big of a problem either.
One thing for sure..... porting the intake will not help the situation one bit, but it will empty his wallet.
He needs to go to a 4150 carb, a 4150 TB, or use a L76/LS3 manifold. Mark my words, if he switches to the L76, he'll pick up power.
He needs to check his plugs, and he'll see that the front plugs are black and the rear plugs are considerably cleaner.
If the elbow was reconfigured to offer a longer short turn, or better yet, a straight section, this would not be a problem. If the engine was FI it would probably not be as big of a problem either.
One thing for sure..... porting the intake will not help the situation one bit, but it will empty his wallet.
He needs to go to a 4150 carb, a 4150 TB, or use a L76/LS3 manifold. Mark my words, if he switches to the L76, he'll pick up power.
05-07-2008, 10:12 AM
#72
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The elbow is not a restriction, it's ruining the airflow and airstream. It's too short and has too quick of a short turn. The air moving across the short turn of the elbow has to turn 180* in such a short distance to get to #1 and #2 port that it's killing power in those two cylinder alone, and probably hurting #3 & 4 as well. Moving air (airflow), just like your car, cannot turn on a dime. It has inertia and has to have ample time/space to turn. As the volume of air goes up, the more time/space (longer s/t) it requires.
He needs to check his plugs, and he'll see that the front plugs are black and the rear plugs are considerably cleaner.
If the elbow was reconfigured to offer a longer short turn, or better yet, a straight section, this would not be a problem. If the engine was FI it would probably not be as big of a problem either.
One thing for sure..... porting the intake will not help the situation one bit, but it will empty his wallet.
He needs to go to a 4150 carb, a 4150 TB, or use a L76/LS3 manifold. Mark my words, if he switches to the L76, he'll pick up power.
He needs to check his plugs, and he'll see that the front plugs are black and the rear plugs are considerably cleaner.
If the elbow was reconfigured to offer a longer short turn, or better yet, a straight section, this would not be a problem. If the engine was FI it would probably not be as big of a problem either.
One thing for sure..... porting the intake will not help the situation one bit, but it will empty his wallet.
He needs to go to a 4150 carb, a 4150 TB, or use a L76/LS3 manifold. Mark my words, if he switches to the L76, he'll pick up power.
94 Guy, It will be soon I fixed my tranny last night so no I need to get into the dyno. I have kinda been waiting on the tax relief money that way I can buy any misc. **** I might need at the shop during tuning. That and it has to be a day I can take off from work because the tuner is full on weekends.It could be as soon as next week though. But dont worry guys I will post up the good the bad and the ugly. I wont keep it to myself. Wize *** might pick up power with the l76 only because now he is running a cam that dont need the intake he has now. As for the 4150tb It sounds like a change I may do to my car.But only after I have got what I have running right first. first.
05-07-2008, 02:27 PM
#73
The elbow is not a restriction, it's ruining the airflow and airstream. It's too short and has too quick of a short turn. The air moving across the short turn of the elbow has to turn 180* in such a short distance to get to #1 and #2 port that it's killing power in those two cylinder alone, and probably hurting #3 & 4 as well. Moving air (airflow), just like your car, cannot turn on a dime. It has inertia and has to have ample time/space to turn. As the volume of air goes up, the more time/space (longer s/t) it requires.
He needs to check his plugs, and he'll see that the front plugs are black and the rear plugs are considerably cleaner.
If the elbow was reconfigured to offer a longer short turn, or better yet, a straight section, this would not be a problem. If the engine was FI it would probably not be as big of a problem either.
One thing for sure..... porting the intake will not help the situation one bit, but it will empty his wallet.
He needs to go to a 4150 carb, a 4150 TB, or use a L76/LS3 manifold. Mark my words, if he switches to the L76, he'll pick up power.
He needs to check his plugs, and he'll see that the front plugs are black and the rear plugs are considerably cleaner.
If the elbow was reconfigured to offer a longer short turn, or better yet, a straight section, this would not be a problem. If the engine was FI it would probably not be as big of a problem either.
One thing for sure..... porting the intake will not help the situation one bit, but it will empty his wallet.
He needs to go to a 4150 carb, a 4150 TB, or use a L76/LS3 manifold. Mark my words, if he switches to the L76, he'll pick up power.
I will buy this theory for a N/A build.
Turning the air that quick will result in very unbalanced airflow to each cylinder, resulting in poor power and difficult tuning.
Even if the low profile elbow he has flowed 1,500CFM does not mean that each cylinder will get exactly 187.5CFM. The intake itself is not the issue.
A 4-barrel TB would help, but packaging an inlet/air filter on an f-body will be the real challenge.
Throw on a turbo or procharger and ditch the nitrous, problem solved.
JKFI is much less picky about these things....
Good luck with it WizeAss, I'm sure you will get it figured out.
The new Corvette LS3 manifold is available from GM now.
I wonder if it will flow better than the L76 version???
05-07-2008, 06:32 PM
#74
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05-07-2008, 06:39 PM
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One thing noone has mentioned yet... the real reason why carbs will always make more absoloute power than FI in an apples to apples comparison...
Latent heat of vaporization.
As the fuel is pulled into the airstream in the venturis, the fuel evaporates/atomizes and absorbs heat to do so. This in turn cools the incoming air charge. Cooler air is denser air and equals more power. It is impossible to duplicate this in any conventional fuel injection setup.
Shane
Latent heat of vaporization.
As the fuel is pulled into the airstream in the venturis, the fuel evaporates/atomizes and absorbs heat to do so. This in turn cools the incoming air charge. Cooler air is denser air and equals more power. It is impossible to duplicate this in any conventional fuel injection setup.
Shane
All somebody would have to do is move the injectors or place a second set of injectors farther upstream......precice control of the fuel distrobution AND cooling.
05-08-2008, 06:24 PM
#76
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I will buy this theory for a N/A build.
Turning the air that quick will result in very unbalanced airflow to each cylinder, resulting in poor power and difficult tuning.
Even if the low profile elbow he has flowed 1,500CFM does not mean that each cylinder will get exactly 187.5CFM. The intake itself is not the issue.
A 4-barrel TB would help, but packaging an inlet/air filter on an f-body will be the real challenge.
Throw on a turbo or procharger and ditch the nitrous, problem solved. JK
FI is much less picky about these things....
Good luck with it WizeAss, I'm sure you will get it figured out.
The new Corvette LS3 manifold is available from GM now.
I wonder if it will flow better than the L76 version???
Turning the air that quick will result in very unbalanced airflow to each cylinder, resulting in poor power and difficult tuning.
Even if the low profile elbow he has flowed 1,500CFM does not mean that each cylinder will get exactly 187.5CFM. The intake itself is not the issue.
A 4-barrel TB would help, but packaging an inlet/air filter on an f-body will be the real challenge.
Throw on a turbo or procharger and ditch the nitrous, problem solved.
JKFI is much less picky about these things....
Good luck with it WizeAss, I'm sure you will get it figured out.
The new Corvette LS3 manifold is available from GM now.
I wonder if it will flow better than the L76 version???
LS3 and L92 are basically the exact same.
As far as the composite, remember the air wants to go from front to back and the back two cylinders on a composite car always run a tad bit leaner, since they have more air and less fuel. Someone told me a way to compensate is using different plugs for those cylinders. Yet you have to consider the timing order and how that effects things as well.
I am sold on the fact that the intake needs work. It does not distribute evenly, and I would assume by porting it properly in the front for more air to move forward you can compensate for the lack of flow to the front 2 runners. I dont think the short turn effects a smaller cube motor as much as one would think, regardless the elbow flows much better than a composite. The increased runner length is definately a concern, but isnt the point of using the elbow to gain more runner volume back that the intake lost?
This whole thing is much trickier than a 92mm/92mm Fast setup with a set of 225 heads and a 200 nitro daves TB Plate up front on hardlines!
My next steps are:
-Port the intake
-Change the converter
-SD Tune the car
-Redo the nitrous kit
-Get some real tires
I would think I can go from a 7.38 N/A down to some 6.9/7.0's... the spray it for my 5.99!
atleast I pray!
05-08-2008, 06:55 PM
#77
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its not necessarily even the power advantage. its more the ability to tune more thoroughly. the efi prostocks may not make more power but they are going faster.
05-08-2008, 08:19 PM
#78
I just got my 427 ported L92/L76 tuned and dynoed as well, and mine went to 90kpa in the early 6's. On the dynojet , the peak #'s were 447hp @ 6300 and 400 tq. @ 5600 in an S10 x-cab with poorly fabbed 1 3/4 headers and non-mandrel bent dual 2.5 exhaust, built 4L60 w/ an 11" 3600 converter, a heavy 2 pc. steel driveshaft, and heavy 18" wheels.
Take that for what it's worth. Even with my crappy headers it still pulled that big of a vacuum in the manifold.
Take that for what it's worth. Even with my crappy headers it still pulled that big of a vacuum in the manifold.
05-08-2008, 11:52 PM
#79
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LS3 and L92 are basically the exact same.
As far as the composite, remember the air wants to go from front to back and the back two cylinders on a composite car always run a tad bit leaner, since they have more air and less fuel. Someone told me a way to compensate is using different plugs for those cylinders. Yet you have to consider the timing order and how that effects things as well.
I am sold on the fact that the intake needs work. It does not distribute evenly, and I would assume by porting it properly in the front for more air to move forward you can compensate for the lack of flow to the front 2 runners. I dont think the short turn effects a smaller cube motor as much as one would think, regardless the elbow flows much better than a composite. The increased runner length is definately a concern, but isnt the point of using the elbow to gain more runner volume back that the intake lost?
This whole thing is much trickier than a 92mm/92mm Fast setup with a set of 225 heads and a 200 nitro daves TB Plate up front on hardlines!
My next steps are:
-Port the intake
-Change the converter
-SD Tune the car
-Redo the nitrous kit
-Get some real tires
I would think I can go from a 7.38 N/A down to some 6.9/7.0's... the spray it for my 5.99! atleast I pray!
As far as the composite, remember the air wants to go from front to back and the back two cylinders on a composite car always run a tad bit leaner, since they have more air and less fuel. Someone told me a way to compensate is using different plugs for those cylinders. Yet you have to consider the timing order and how that effects things as well.
I am sold on the fact that the intake needs work. It does not distribute evenly, and I would assume by porting it properly in the front for more air to move forward you can compensate for the lack of flow to the front 2 runners. I dont think the short turn effects a smaller cube motor as much as one would think, regardless the elbow flows much better than a composite. The increased runner length is definately a concern, but isnt the point of using the elbow to gain more runner volume back that the intake lost?
This whole thing is much trickier than a 92mm/92mm Fast setup with a set of 225 heads and a 200 nitro daves TB Plate up front on hardlines!
My next steps are:
-Port the intake
-Change the converter
-SD Tune the car
-Redo the nitrous kit
-Get some real tires
I would think I can go from a 7.38 N/A down to some 6.9/7.0's... the spray it for my 5.99!
atleast I pray!
05-09-2008, 09:00 AM
#80
LS3 and L92 are basically the exact same.
As far as the composite, remember the air wants to go from front to back and the back two cylinders on a composite car always run a tad bit leaner, since they have more air and less fuel. Someone told me a way to compensate is using different plugs for those cylinders. Yet you have to consider the timing order and how that effects things as well.
I am sold on the fact that the intake needs work. It does not distribute evenly, and I would assume by porting it properly in the front for more air to move forward you can compensate for the lack of flow to the front 2 runners. I dont think the short turn effects a smaller cube motor as much as one would think, regardless the elbow flows much better than a composite. The increased runner length is definately a concern, but isnt the point of using the elbow to gain more runner volume back that the intake lost?
This whole thing is much trickier than a 92mm/92mm Fast setup with a set of 225 heads and a 200 nitro daves TB Plate up front on hardlines!
My next steps are:
-Port the intake
-Change the converter
-SD Tune the car
-Redo the nitrous kit
-Get some real tires
I would think I can go from a 7.38 N/A down to some 6.9/7.0's... the spray it for my 5.99! atleast I pray!
As far as the composite, remember the air wants to go from front to back and the back two cylinders on a composite car always run a tad bit leaner, since they have more air and less fuel. Someone told me a way to compensate is using different plugs for those cylinders. Yet you have to consider the timing order and how that effects things as well.
I am sold on the fact that the intake needs work. It does not distribute evenly, and I would assume by porting it properly in the front for more air to move forward you can compensate for the lack of flow to the front 2 runners. I dont think the short turn effects a smaller cube motor as much as one would think, regardless the elbow flows much better than a composite. The increased runner length is definately a concern, but isnt the point of using the elbow to gain more runner volume back that the intake lost?
This whole thing is much trickier than a 92mm/92mm Fast setup with a set of 225 heads and a 200 nitro daves TB Plate up front on hardlines!
My next steps are:
-Port the intake
-Change the converter
-SD Tune the car
-Redo the nitrous kit
-Get some real tires
I would think I can go from a 7.38 N/A down to some 6.9/7.0's... the spray it for my 5.99!
atleast I pray!Good luck reaching your goal!
Maybe try changing one thing at a time to narrow down the problem.
1) Tune the car SD
2) Maybe try a different elbow (shorter length and smoother radius)
3) Port the intake (I would not expect a big gain but who knows)
4) Converter
5) Nitrous
It is easy to find fault in different parts of the combo and make a bunch of changes at the same time.
Even if the car improves, you have no way to tell what fixed it.
It will help dial in the next combo a little easier.
(I learned this the hard way tuning my last blowthru carb setup)
Even switching to a better elbow on my Procharged setup made a very impressive change.
Having a low profile elbow that turns the air abruptly will be a factor, but how much it affects distribution and power will vary by each combo.
I'm no EFI expert by any means, just thinking of some options...
Hope it works out for you.