Best way to choke a 408 N/A..... unported GMPP L92 Intake FTL!
04-26-2008, 05:30 AM
#41
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I agree with PatrickG. Maf tunes are for stock cars. There is NO need for a closed loop tune when you KNOW what you are doing/looking/listening for. Judson @ SAM said himself "Its very hard to beat a two carb setup on a tunnel ram." To me speed density tunes and carbs are one in the same. I REALLY want to try my hand at tuning but my time is EXTREMELY limited.
We had quite a few problems with reversion using a carb on this intake with these heads BTW. Had to use 3 inches of spacer to get it to idle.
We had quite a few problems with reversion using a carb on this intake with these heads BTW. Had to use 3 inches of spacer to get it to idle.
You will see only good WOT afrs with tunnel ram. Plus you can smooth that big cam engine of yours with efi SD tuning.
04-26-2008, 06:58 AM
#42
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The vacuum is coming from the elbow, not the intake
Lose the elbow, find a 4-bbl TB and gain 20+rwhp
For kicks, we tested an unported GMPP with 4-bbl Accel on 383 stroker. Made 15rwhp, 100kpa till 7000rpm (where the cam fell over). Held on to peak power an additonal 300RPM - but this cam is way too small
No losses down low. Throttle repsonse - nothing like a banana back LS1. Kicks like a mule off idle - worth it for that alone.
Lose the elbow, find a 4-bbl TB and gain 20+rwhp
For kicks, we tested an unported GMPP with 4-bbl Accel on 383 stroker. Made 15rwhp, 100kpa till 7000rpm (where the cam fell over). Held on to peak power an additonal 300RPM - but this cam is way too small
No losses down low. Throttle repsonse - nothing like a banana back LS1. Kicks like a mule off idle - worth it for that alone.
04-27-2008, 08:48 AM
#43
The way droplets atomise?Fuel should spray into the chambers. The combustion chamber sees a perfect amount of atomized fuel per cylinder with efi multipoint. You will get varying afrs with a carb on single plain manifold. It would be more than fuel droplets atomising, more so with air speed,
They used to fit carbs to V8 supercars in Australia when on a budget with single plain manifolds. They lost hp and torque and greater average hp over a 8TB harrop manifold flat side efi. And I dont see motoGP bikes make 240rwhp from 800cc with holleys strapped to them.The aussie V8 supercars make 700hp from 5 L with injection. History shows you are one of few to get such results
In your case a 100hp loss shows something poorly miss matched. That manifold and Big *** 1000cfm+ TB was to big, either that or someone cant tune SD with such a massive camshaft. History shows efi wins the majority hands down.
In Wizes case. A stock 6L will get 99kPa. How you only get 91kpa gets me stuffed. Thats like a blocked vaccum cleaner! A typical efi manifold likes a single TB but single planes work better with a carb or 4B throttle body. That elbow will restrict flow as that manifold isnt designed to work with it. Unless FI is brought into equation.
So there is no doubt a carb will make more over the current setup. How come you dont ditch the elbow and MAF and tune SD, will see results then, only other option is to fit a weiand warrior.
cheers
They used to fit carbs to V8 supercars in Australia when on a budget with single plain manifolds. They lost hp and torque and greater average hp over a 8TB harrop manifold flat side efi. And I dont see motoGP bikes make 240rwhp from 800cc with holleys strapped to them.The aussie V8 supercars make 700hp from 5 L with injection. History shows you are one of few to get such results
In your case a 100hp loss shows something poorly miss matched. That manifold and Big *** 1000cfm+ TB was to big, either that or someone cant tune SD with such a massive camshaft. History shows efi wins the majority hands down.
In Wizes case. A stock 6L will get 99kPa. How you only get 91kpa gets me stuffed. Thats like a blocked vaccum cleaner! A typical efi manifold likes a single TB but single planes work better with a carb or 4B throttle body. That elbow will restrict flow as that manifold isnt designed to work with it. Unless FI is brought into equation.
So there is no doubt a carb will make more over the current setup. How come you dont ditch the elbow and MAF and tune SD, will see results then, only other option is to fit a weiand warrior.
cheers
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
04-27-2008, 10:09 AM
#45
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Think about one thing for me for a second....NHRA Pro Stock.
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
04-27-2008, 12:45 PM
#47
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I am going to have mine ported and attempt to run both the carb and the L76..... I just need to make sure the Aeromotive rails fit the L76 and the 42lbSVO injectors work as well..... For street use and the winter I can run the car manifold and a TB Plate, and for track time I can swap to the GMPP to run the 300-400 shot of nitrous.
04-27-2008, 01:53 PM
#48
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Think about one thing for me for a second....NHRA Pro Stock.
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
I think he was more getting at the point that EFI makes better overall drivable power, like one would need on a roadcourse
04-27-2008, 04:52 PM
#50
I am going to have mine ported and attempt to run both the carb and the L76..... I just need to make sure the Aeromotive rails fit the L76 and the 42lbSVO injectors work as well..... For street use and the winter I can run the car manifold and a TB Plate, and for track time I can swap to the GMPP to run the 300-400 shot of nitrous.
I run FAST fuel rails and 42 Green Tops. You will need to get some o-rings from Ktech for the L72 intake.
04-27-2008, 10:38 PM
#51
But since it was brought up, You can take Nascar into the road racing category. They do run on road courses and are not always at WOT....hmmm do you see a pattern here?
Those motors generally see a super lean condition and as high as 18:1 AFTER peak torque to make power and conserve fuel and they rarely burn up. Why is that????
05-01-2008, 01:06 AM
#52
Think about one thing for me for a second....NHRA Pro Stock.
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT! Thats all I need to say on this subject. You obviously have no first hand experience with as I do.
05-01-2008, 09:33 PM
#53
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Since when is NASCAR the epitome of engineering for road racing, much less racing in general? They run carbs because that's what the rules say they have to run.
If you are looking at NA power density, look at Formula 1 - 2.5 liters, close to 900 horsepower. They are certainly not running carbs.
Lighten up Howie.
If you are looking at NA power density, look at Formula 1 - 2.5 liters, close to 900 horsepower. They are certainly not running carbs.
Lighten up Howie.
05-01-2008, 09:42 PM
#54
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actually you are wrong on several points here... NHRA P/S is not the world's fastest na class... that would most likely be IHRA P/S or some other mountain motor class. and Warren Johnson (who needs no introduction) has been saying for years that FI would make their cars quicker, and give them the tunability needed to make them leave harder, etc. (an NHRA stocker leave harder? ya, crazy to even think about...)
05-02-2008, 09:59 AM
#56
I can see with the fully computer controlled cars like F1 want EFI for on the fly changes or monitoring but I would bet NASCAR would stay carb. WOT power can't be matched and that is all they do.
EDIT: I can see the argument on what cars or type of racing could benifit from EFI but it seems the people with real experience with both seem to agree about WOT power going to a carb.
EDIT: I can see the argument on what cars or type of racing could benifit from EFI but it seems the people with real experience with both seem to agree about WOT power going to a carb.
05-02-2008, 11:16 AM
#57
Howie FB:The world's fastest N/A Class...Don't you think if injection was truly the way way to go to make more power then carb's these guys would be ALL OVER IT!"
Could it be that NHRA does NOT allow it in P/S???
WJ tested efi here, at Atl Dragway. His comment to me: EFI @ the initial testing was as good as any carb system he had. The big winner was gaining 40 Hp, due to losing the parasitic drag loss of that fugly hood scoop. [Engine was fed w/ ram iar inlets, and a smooth hood]...
Ya, Howie.. maybe a little "feel r' bush", and you'll calm down!!
Could it be that NHRA does NOT allow it in P/S???
WJ tested efi here, at Atl Dragway. His comment to me: EFI @ the initial testing was as good as any carb system he had. The big winner was gaining 40 Hp, due to losing the parasitic drag loss of that fugly hood scoop. [Engine was fed w/ ram iar inlets, and a smooth hood]...
Ya, Howie.. maybe a little "feel r' bush", and you'll calm down!!
05-02-2008, 03:01 PM
#58
Real power per ci is found in formula 1, and guess what. Thats right EFI. The reason for not allowing EFI is because of class rules. A lot of sanctioning bodies, circle track and drag racing alike, do not want EFI because of traction control and all the electronic cheats you can do.
Why do you think they run roots blower and not turbos in top fuel. It sure the hell is not because a roots blower is more efficient lol.
Why do you think they run roots blower and not turbos in top fuel. It sure the hell is not because a roots blower is more efficient lol.
05-02-2008, 03:31 PM
#59
yeah but they are boosted and need to be able to change boost levels and other fueling parameters on the fly if needed.( I think they are boosted still, I don't follow F1)
I do agree on carbs making it easier to keep people in check with rules for sure though! Equip an engine with computers running everything and enforcing rules becomes almost impossible.
I do agree on carbs making it easier to keep people in check with rules for sure though! Equip an engine with computers running everything and enforcing rules becomes almost impossible.
05-02-2008, 08:37 PM
#60
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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