Alternative Port EFI IntakesThis board is for tech discussions and questions about aftermarket port EFI such as the HSR, MR, SR, BBK, FIRST, etc.
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In general, it will make things work better... OTOH, if you're not great at tuning you may not notice the difference and even if you do, there is always the concern of things coming loose inside the intake tract and getting ingested into the engine.
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Well I dont see how the divider will break loose I just want to be on the safest side of things when I put some boost at this motor. I want the best distribution possible and from my research, the single plane is the way to go. Front mounted TB setups always have a distribution problem unless you make a custom tapered plenum which I dont have ability to do and dont want to pay for a custom sheet manifold
well, the divider doesn't stand much chance getting ingested, but whatever you use to locate it might. Also, it wouldn't take much motion from a divider like that to totally screw up airflow to a few cylinders.
Why wouldnt you just weld in the divider? no change of movement or ingestion, i wouldnt do it any other way. As for the TB id use a 58mm oem style, not the LS.
I'm leaning towards the elbow with the 58mm TPI tb i already have. I have heard a few quality issues with this elbow tho, but we'll see
If I decide to take the blower off the car I may use the edelbrock elbow for the LSx throttle body.
I like the blower but, it doesn't create a whole lot of boost, and with the air filter positioned next to the header, and the static compression ratio of the motor I often wonder if the car wouldn't make as much power with just more advance and the filter located in the front picking up cool air.
Though people have said it will make more power with the blower, I still wonder. I should take it out tonight and do a wot blast to 6000 to get an idea of how much boost this powerdyne is actually making.
This is of course, assuming the car is not sold this weekend. I'm half hoping it is so I can start a '67 firebird, or '69 vette project.
Does that thing fit under the stock hood OK? I have that manifold, but with a low profile carb hat and 1000 CFM progressive TB, and I had to hack out the supports to get it to clear, especially where the MAF is. Gets kinda tight as teh hood slopes down.
Last edited by dimented24x7; 08-27-2009 at 08:41 AM.
Back on the turning vane (air divider) issue, I pulled the driver's side head of my turbo motor after a year to take a look at the pistons. My intake elbow does not have a turning vane. Additionally, the butterfly valve in my throttle body is designed such that the top half of the blade rotates inwards as it is opened, which tends to direct the air upward and down the back of the elbow at partial throttle.
Looking at the pistons, they are progressively cleaner from piston #1 to piston #7. The engine was run soely off of E-85. The deposits on the pistons are wet as I fogged the cylinders with oil prior to taking the engine apart. Injectors are flow-matched 120lb/hr trickflow units.
I will be adding a turning vane to the elbow this season to see if there is any change.
I don't think a turning vane is really the right answer. Yes, it will make things better, but to a large extent, they will be better because you're splitting airflow into narrower chunks/slugs that are badly distributed. I suspect that that might get you close enough to good that for most purposes it won't really matter that it's not _right_ but in a lot of ways, I'm interested in what actually works correctly.
That said, what we're trying to fix is the heavy/dense air sticking to the outside of the curve (the back of the elbow or even plenum on something like an LT1 intake) and then dumping down the back runners leaning them out. That means either totally redirecting airflow or inducing turbulence where there is too much airflow. To that effect, I think the right solution would be either opening the TB into a plenum that extends past the openings of the plenum in the manifold, giving the airflow no clear path that it can stick to a smooth surface all the way down to the runners (I'm afraid that might hurt response, maybe, maybe not), or (and?) a using a diffuser to break up that strong, dense flow that is causing the problem.
Never got a chance to check my spark plugs and such since i'm running a elbow with divider. I have noticed header surface temps drastically different from rear to front but not sure how much i trust the gun i'm using... its hard to get accurate readings with it.
Car has been running ok so not sure what is going on.
well, as long as the leanest cylinder is rich enough, you're not likely to hurt anything (it is actually possible to go too rich and get detonation from that, but unlikely) but then if you're going to do some tuning with a WBO2 you'll have to know what that reads at the point where the leanest cylinder is OK. At that point you're loosing some power, but at least you're not hurting the engine.
my original intent was to monitor EGT's on each cylinder but I never installed bungs on the header for that. I did have a bung to monitor air fuel on both banks downpipes, but the driver side one sealed shut, i cant get the plug off to get the o2 sensor in, so i'm gonna have to do something about that if i want to read the right bank. May need to install one in the bottom of the downpipe where the exhaust bolts to it. Thats easily detachable. Its off the car now, i may put bungs in both sides. YOu cant go wrong with more than 1 bung hole
I just want to be on the safest side of things when I put some boost at this motor. I want the best distribution possible and from my research, the single plane is the way to go. Front mounted TB setups always have a distribution problem unless you make a custom tapered plenum which I dont have ability to do and dont want to pay for a custom sheet manifold 
14psi, street tune 
