I am always looking for things! In the pursuit of more Horsepower from what you have. I noticed something.
Check your intake! I discovered that your intake tube may need
adjustment. Remove the front A&A cover exposing air filter and intercooler.
Mark your intake tube, all the way around with a marker, right at edge of the filter lip. Then remove the tube. The mark around the tube should be 1 and 1/4 inch from the end. Mine was 3 inches. Pretty sure most are like this. This is restricting the air filter flow by having the tube way too far into the filter. I cut off almost 2 inches.

Then replace those 2,90 degree rubber intake elbows with 3 inch
alum. Then replace the front rubber 120 turn to the cooler with a 3 inch 120 degree pipe.
I rechecked my before and after dyno's. When I switched to a larger
header which should have reduced boost. Instead it went from 8 .03
max to 9.01 max Gaining a full free pound of boost! Horsepower/TQ
went from 513 and 453. To 578 and 530. Haven't checked after the redoing the Air filter! But it feels nice! Both are near free power!
under car picture!


Front connection

 

I thought that Andy had revised his kit during the past few months to remedy these restrictions, especially after you posted this a while back, when switching your header size?

 

I'd like to know a little more about this as well

 

Let me see if I understand this correctly, you increased the ID of the intake tubing and straightened out flow a bit and gained 65HP and 77 TQ??

Was the tune changed?
Was the dyno the same?
Was the weather similar when tested?
Besides the larger primaries on the headers, is the exhaust the same on the entire system?

513/453 is anemically low for a blower car with headers so something else was wrong with the car before the intake tubing change. 578/530 seems to be about middle of the road, probably even low for 9 psi through 1 7/8 headers. Not trying to discredit what you are saying , I just seem to remember there was more to this power gain than a bit of intake piping change. Before people run out and do it and think they will achieve these gains by switching out some tubing, its good if they know what to expect. A properly breathing, properly tuned car will NEVER make those kinds of gains (65/77) by massaging the intake tubing a bit.

 

Well the kit has alot of rubber hose's, Hardpipe's will always free up alot of HP due to the pipes not being able to flex.

Thus increasing boost. hints your gain in PSI

 

Gained 1 psi!

 

597whp here with the stock rubber hoses and 1 3/4" headers...

 

Still don't know why you resist!
Coming to the darkside so I am sending you 2 elbows. Since I like you so much! I'd buy you the front one ( 120 degree) but it's 55 dollars! Just pm me your
address. Gonna bring that rwtq up! Most likey the HP too. P. S. Check that Airfilter you will see, Then you will thank me!
Remember my gears are reflecting somewhat less in my numbers!

 

If this did gain me 65 whp, would I need to re-tune?

Mine is a different deal being that my kit has ECS pipes & hoses (mostly aluminum anyway), but I will definitely be looking at the intake tubing.

 

Guys if this really brought you up 65rwhp, don't you think A&A would just make the change... hardly any additional cost to them & they would get way better #s... come on.

 

This for the A&A kit only thread!. and don't even expect 65 rwhp. But if the gain
1 psi and what it's hp maybe worth, it's a great deal!

 

maybe not 65 HP exsactly but look at it this way.

Hardening pipes increase air pressure = making psi gain = more HP, probably around 20 hp per lb of boost give or take , he added headers to his car if he'd stayed on stock headers he might have gain 2 or more boost over what the stock piping provided making the 60hp gain he's talking about. I wouldnt call him a liar until you can provide that all the other factors are void.

Ever think this is why APSTT kit says useing factor headers is recommended over aftermarket? More flow reduces your Pressure in your exhaust system and only way to make up for it is a boost controller to turn the pressure back up.

 

Maybe he had a sock stuck in the tube?

 

I'm not calling anyone a liar, I'm saying if it were as simple as switching the tubes and you instantly gain 65rwhp, don't you think A&A would do this? I wouldn't mind seeing the dynos for both of the runs.

And I'm not talking about headers changing, I'm talking about him swapping the tubes. There are so many other factors, and dynos can show various different numbers between pulls on the exact same car..

 

The APS kit includes a set of headers
But don't ever confuse pressure with power. Boost is a measure of how much air you can NOT flow through your engine. Adding headers, cams, ported heads, etc all cause boost to DROP and power to go UP.
If the amount of boost was an indication of how much power you are making we would all run a tiny exhaust pipe so there would be as much restriction as possible for all that air to get out of the engine

 

I knew the deal with the air filter... You are absolutely right; I was actually going to do what you did when I get around to cleaning it
I'll do a dyno comparison with these elbows; just PM me where I can buy the front one too, I'll gladly take these off you and then I can d the whole kit like yours. I must warn you though; there is really no scientific basis for any real power gain coming from this, so I am expecting it to be no different than the dyno comparo; you were SURE the larger primaries netted you those power gains and I demonstrated that the gains were MINIMAL; not even high enough to be past the accuracy of the dyno.
The bottom line is this: that pulley on the blower controls how fast it turns and thus how much air it will move. Your engine determines how much air flows through it (chiefly via the camshaft) and the tune determines how efficiently you use that air to make power. Your tune changed and that is where all that power came from; you went from making a lot less than a similar car with a similar kit, to making the same numbers a similar car with this kit makes. My car was always tuned right so even when we put larger headers on, there was nothing substantial to be gained even by altering the tune. The only way I am making more power is if I cam, up the boost, run race gas or meth and tune for it, or port the heads.

I really need to get around to making that post about how you can calculate power for a supercharged car Its pretty simple!

 

Your header change was primary size only. Mine was was also x- pipe and exhaust change from 2 1/2 to 3 inch. It was a combination of that and the piping change more than the tune. Both tunes were 12 degree total timing same tuner. Tuned the same way, Tuner's tune them the same way each time and thats it, sets the AF and looks for certain values, If it wasn't tune his tunes would not be consistant, like they are or people would be having problems. It was tuned the same way, Header and more boost pressure,
like I should have lost some boost! I bet you lost some boost. I gained a pound with more exhaust difference cfm out change than you. Not so much tune! Next you'll be thinking your car is as fast as mine! Just kidding!

 

What is the air filter thing you guys are talking about? I have a two year old A&a kit and probably have the old design.

 

Ohh, I didnt mean that LOL. Just saying that him free'ing up his exhaust lowered his boost pressure within the engine. and him being able to turn it back up to what it was suppose to be to gain that power, and the adding of the hardpipe to keep the original ones from flexing.

Hose flexing is a issue on all FI cars that have alot of rubber hose's, Thats why companies sell aftermarket I/C kits for the shorter routing and eliminating flexing. But you know that You and me both came from turbo'd awd cars

 

I found my intake to the blower was in the filter over 3 inches.
When it is 1 1/4 inches to be flush inside the filter, blocks the airflow
so I cut mine off, flows better air now!
Mark the outside and pull it a part to see. Or just wait till you clean it
then fix it!