The Project Pad

When the car is running you should be able to adjust the screw on the throttle body till you get 430 ma. But you have to adjust the frequency valve duty cycle at the same time.

Deciding on mufflers. Anyone got sound clips of catless 20vt? Im really looking at going with the brand thats on my truck but a step quieter. A spintech with 3" in and dual 2.25" out. Should sound pretty good.

That should sound amazing. But I was warned that a 20vt in a small chassis with only a rear muffler is quite loud. Im going to try just my starbro(I know I spelledbthat wrong) and see how bad it is before I put in a Borla resonator.

With an open downpipe, it isnt bad at all IMO. The drone is bad but thats to be expected with an open pipe right under the cab. The turbo is a good muffler on its own lol.

I had a Magnaflow resonator and Dynomax rear muffler on mine. Sounded decent from what I remember. Lots of good options out there. Custom is the way to go, IMHO.

You will want to use a resonator along with the muffler. With just the muffler you will find that the resonation will be too much for long drives.

I think you can figure out whos car this is by the authors name. Exhaust is 3" with a puch core resonator and one muffler(magnaflow IIRC).



Link to video

Wow thats loud even with a resonator. Sound good too

If I do go with the spintech, Im going to hold off on the resonator till I have some driving time.

2 reasons:

Lack of funds atm
My truck with dual 9000s (a small block V8) has very little resonance. Compared to the flowcrap on my old Dakota, these are super quiet in the cab till you open it up. The 6000 I want for the car should be considerably quieter so I will decide after driving

Im thinking I might throw the JT cam in tonight and see what happens to the vacuum. The small overlap may be an advantage. Its only .20 degrees. Would be better for cruising thats for sure. Anyone here run a JT cam with a turbo 20v?

I had a JT head on a MC block in my old 4k. Didn't seem to bad at all

Ok, I know what Im going to do. Bpv port is getting welded today. New ISV is on its way. Im going to see what happens with those 2 fixed first. Then when the vacuum is still horrible, Ill throw a different cam in.

If you end up getting tired of the ISV just delete it. I did that on my 4ktq after the one I got with the motor took a dump and couldnt be revived after cleaning. The next one I tried failed not long after. I just plugged the ports and called it a day. Car ran great for a year or so after that.

How was idle quality? Ive heard that no ISV = vibrations and harsh idling

Idled just fine. Since I didnt have AC the ISV really ddint matter too much to me. Adjusted the idle a bit and I was good to go.

AudiSport4000 wrote:Idled just fine. Since I didnt have AC the ISV really ddint matter too much to me. Adjusted the idle a bit and I was good to go.

Interesting, maybe I should look into this, im not keeping ac in my 80 so the isv really isn't needed?

I could have been mis-informed years ago about that. After the first ISV took a dump (3000rpm idle FTL) and the second one didnt last long either I gave up and asked about it. Snag a few dizzy rotors and block the ports off and enjoy.

I deleted mine soon after i got my car running. Filled it with silicone. It will have to warm up before any decent idle, and it will be finicky after that, but you are dealing with that now anyway. I wouldnt delete it entirely just yet though, you will want it for when you go EFI. It will work much better that way.

My old 20vt 4k had a 2.5" Turbo back exhaust with a cheap cherry bomb muffler on it and it sounded great IMO. Had quite a drone but i didn't mind. For a while I had just a 2.5" straight pipe....badass

I would keep the ISV if that thing is your DD. Cold starting in winter won't bee too much fun without it. Might make you late for class.

Also, I think the JT cam is a good idea. There really isn't that much difference between the JT cam and the MC cam.

FWIW I never had much of an issue, if any with my 4ktq in colder NE IN winters. Just my .02.

GTJeff wrote:I would keep the ISV if that thing is your DD. Cold starting in winter won't bee too much fun without it. Might make you late for class.

Also, I think the JT cam is a good idea. There really isn't that much difference between the JT cam and the MC cam.

LOL yeah no kidding. Last thing I want to do is drive the truck in snow. I'd end up in a ditch or up-side down :(

Alright finally got more parts on the way. Corey is sending me the bumper brackets I need, a good ISV, trunk and door seal, CIS fuel pressure tester kit, and other various goodies.

Pkw was kind enough to sell me an adjustable cam gear too for $65. All that should arrive next week which means I can finally dial the tune in and drive the car into town. Im thinking a 1-3 degree advance on the cam should clean up the idle alot and fix the cruising and idle vacuum

Muffler ordered! Ended up going with my original intention. Spintech 6000 with single 3" in and dual 2.25" outs

Excellent

Why three inch exhaust on a stock 20vt? THats going to drone like a mofo. Not hating at all this car is sweet.

I decided on 2.5" for my 20v with turbo upgrades in mind. It won't choke it up until 400 horse and be much more liveable

Just ordered up all the stuff i need for my new exhaust. 3" stainless with a borla proXS muffler.