Just curious if you had any pictures of the entire exhaust? I saw the header, but running two cat's in california in the stock locations might be pretty nice for a street car Especially at your reasonable sound levels

 

I don't think I do. I should, because I dropped the entire exhaust about three months ago when I was working on the rear camber links... but I didn't take any pics.

I won't be in Packwood. The farthest west that I'm going is Lincoln (twice).

 

nice job yesterday John. Congrats on the 3rd in PAX

It seems I have completely forgotten how to drive on asphalt after rallycrossing for a season. you beat my best time by well over 3 seconds and that's before my cone.... *sigh*

How'd your car compare to Ian's on the dyno? and how come he was in SMF last weekend, is he switching classes?

 

Ian's STS car is in pieces still so he's car-whoring for a bit. We're towing out to Lincoln together at the end of May so I expect his car will be back together soon.

On the same dyno, I think his car made 115 whp peak but with a narrower powerband. Still, his car only weighs around 1900lbs.

I was out on course while a buddy of mine was working in the morning session so I saw all of your runs. If you want to chat shoot me an e-mail..

 

PMed

 

Props for doing your hw and following good build strategies. I have found the fc to be much faster in autox without a rear sway bar and a heavy upgraded front. Allows great power application and braking with minimal side effects, the most prominent being some vagueness during slaloms.

Zack

 

I've tried it both ways, and with how small the stock sway is it doesn't do much, but it's nice for fine tuning corner exit behavior.

 

why you stalking me zack? lol

my rear bar was causing my rear inside tire to skip noticably on braking+turning, so i pulled it, but that may have been due to much higher cornering force (315 v710's).

with street tires i imagine the rear inside is still usable.

 

You should fix the rear brake bias on your car. It makes it infinitely more driveable.

 

yah helical diff may have something to do with it too.. theyre a bit unhappy when they leave the ground. in my experiance my brake bias is about perfect. locks the front at high rpm, rears at low.
i have an ls1, so theres quite a bit more inertia to lock up

 

The dyno got me thinking. That dip in torque seemed like it was some sort of intake-related issue. I had the bright idea that logging airflow with the RTek as measured by the AFM would maybe give me some insight. I saw a dip in airflow between 5200 and 5600 RPM. Immediately I figured something was up with the VDI - maybe the air pump wasn't working correctly or the VDI was slow to open.

I wired the VDI into the "high RPM" position and the "low RPM" position and didn't see any effect in the dip. Hm. To be sure, I checked the aux ports wired open and closed, and the dip didn't move.

That led me to think it was an intake resonance problem. I had been using the stock intake tube, stock airbox, stock snorkel. For giggles, I removed the airbox and ran with no filter for a couple pulls. Better - the dip flattened out a bit and airflow at high RPM improved BIG TIME - but the dip was still there and there was lots of "noise" in the airflow measurement.

Finally, I decided to use the custom aluminum 3.5", smooth bore intake tube that I picked up from a race shop. It was originally made for a race car that used a custom airbox where the passenger's headlight would be, so it needed a lot of modification to work with the stock AFM. It had no connections for the BAC or the crank vent tube, so I fabbed connections for those. I picked up a 3.5" silicone coupler to connect the AFM, and the biggest high flow filter I could find. It's an AEM dryflow, 6" diameter and about 10" long.

I ran a 4" dryer duct from the front grille, through the gap between the radiator and the radiator bulkhead to below the filter (in addition to the stock snorkel). I have a mockup of an airbox / shield, but it isn't done yet. Still, I thought I'd take a few airflow logs with the setup as it sits to see if it made a difference.

As you can see from the plot, the custom intake picked up flow all across the board, flattened the dip and picked up big airflow up top - even compared to no filter at all! Stock is yellow, blue is no airbox and stock intake tube, and maroon is the custom tube and the cone filter. I'm not 100% sure this will translate to more power on the dyno, but I think it should, especially after more fine tuning of the ECU. I ran multiple pulls with the stock airbox and with the new tube, and the measurements are very repeatable. It's a very solid gain across the board.

I never thought cone filters did anything on NA cars, but this data definitely changed my mind. Now I need to get back to the dyno!

 

Great work and a very nice improvement in airflow. I hope it translates to gains on the dyno.

 

This is phenomenal data. Not sure why it took 25 years to get airbox flow info, but keep it up. A turbo must have absolutely abysmal airbox losses. If the engine consumes more air, then the power must increase accordingly (as long as you have sufficient fuel). You should expect to see about an 8% increase in peak horsepower.

Great suspension info also, and incredible driving skills. Top 3 in PAX is amazing. This thread is full of win!

 

you are correct! my FC wishes it was like this one

 

Finally finished my air box / heat shield. Not beautiful, but functional. It's .063" 6061 Aluminum with some heat reflecting material on the inside. The top of the box is fed by the stock snorkel and the bottom of the box is fed with a 4" dryer hose that routes between the radiator and the lower frame in front.

AFM air temps on a 75 degree day went from 130-135F at cruise down to 80F.

 

that's very nice!

 

Did it affect the manifold temps at all?

 

Still running the 225/45/15 Hankook RS-3's this year?

 

I got a set of 225/45/15 Toyo R1Rs that I've been playing with so far since it's been cold.

Right now I'm fighting a problem with my VDI valve not opening fully and quickly. Annoying. The New Jersey Prosolo is this weekend and I'm debating pulling the manifolds and checking out the VDI to see what's up.

 

how do the Toyos compare to the RS-3s so far? I currently have a set of RS-3s on order for the corolla but they're back-ordered like crazy...

 

why not activate it using like... co2 or compressed air at like.. 100 psi? im sure that thing will fly open faster than a strippers legs at the sight of a $100.

 

i dunno about co2, but the FD uses vacuum and pressure storage tanks to be able to open and close the sequential turbo stuff against the exhaust pressure, granted you don't have 10psi to work with like they did, but its an idea....

 

I local guy, tofuball used to use some sort of air pump for his vdi and aux ports... I'm not sure what the details were though. you can pm him if you're curious.

 

I'm up here at the NJ ProSolo and currently sitting first after day one. Not much of a lead, but it's a lead.

I did some testing and the VDI is not opening consistently. It will start to open at 5200, but it doesn't open fully. It's as though it's not getting enough air pressure. I tried bypassing the solenoid and hooking it directly to a pressure line and it does open, but if I floor the throttle the pressure on the line drops and the VDI closes.

I ruled out the electronics and the solenoids... my best guess is there is a leak in the air pressure delivery system somewhere, or the air pump is dying. I may try to pick up a lower mileage air pump before lincoln.

It's a big power drop with the VDI not working, I can see it in the data. Grrrr.

 

is it weird that the throttle position affects the air pump pressure? maybe when the ACV opens to dump the air pump air, the air pump cannot keep up? its a little odd but it would be a valid move to put a restrictor in the air pump dump hose...

if you came up with some way to test the air pumps, i'd be happy to see if any of mine are ok