Well got the new turbo put on today, ran into a couple of issues but we got everything worked out and it turned out nice. Ended up having to make a downpipe flange (4 bolt), and then the rest of the downpipe. As far as the difference in how it drives is night and day. My previous setup was a cast iron log manifold with a t3t4 50 trim turbo and a 2.5" downpipe. I would see full spool at around 3500 rpm and because of the back pressure with this setup my torque curve was nice and broad. This setup is really nice for dd and for the person that wants to stay conservative with their tune and power goals (under 400hp). I liked this setup because it felt like there was always power on tap whether you were at 3000 rpm or in 5th gear cruising and you needed to pass somebody without having to downshift!!
Now with the new setup I have a ramhorn manifold and a 60-1 turbo .82 a/r hot and 60 trim cold and a 3" dowpipe. I picked this setup because I'm wanting to run a higher lift cam and make the same mid 300hp with less boost= more effecient. Because of my want to run the higher lift cams I had to reduce the amount of back pressure after the exhaust cam. Going to a ramhorn manifold, a larger (.82 a/r) turbine housing and a 3" downpipe achieves this perfectly.
First Drive:
Like stated earlier the difference is night and day, instead of full spool at 3500 rpm, I'm at full spool around 5600 rpm (right at vtec engagement). I can tell that a little bottom end (torque) has been loss, but with the addition of higher lift cams I should be able to get some of that lag and torque back (closer to maybe 5000 rpm spool up). Even though I was expecting this drastic difference I was still thrown off a little, but I will tell you one really, really good advantage. Because I'm not reaching full spool until around 5600 rpm, I can stay out of boost when I'm just put putting around town which= better gas mileage. Just on one tank of gas I went from an average of around 24 mpg to 28.3 mpg. Another great advantage is when this turbo finally spools man oh man is it nasty, I have a 6lb wastegate spring in right now and it feels like when I was running at 10lbs of boost with the smaller turbo!!! Freakin Nasty!! Ok sorry back to the great gas mileage lol- I'm going to keep tabs on it but I was able to go a substantial amount of miles more than normal.
A couple of things that I'm trying to keep in mind as far as the cams go is I'm wanting to make sure that the primary and secondary cam lobes are going to be a little larger than the current GSR cams that I'm running now. This will aid in reducing lag and hopefully getting my torque back up there a little. I'm trying to not just get tunnel vision on the max amount of lift (vtec lobe) that the cam is going to give me, I want it all!!
I'm planning on trying to do some videos of some driving impression on Sunday, if I'm able to do it I'll try to edit it really quick and get them up. Then that way for some of the guys that prefer videos (like I do) you can physically see what I'm talking about.
Stay tuned....pics:
As always a big thanks to the guys at Mainstream Performance, there the only guys that I would trust!!
www.mainstreamperformance.com
Turbo comparison, t3t4 50 trim on left, 60-1 on right!!
Undercarriage shot, had to modify a few things to get everything to fit propery.
New turbo mounted:
Close up (well kinda) of the downpipe.
Thanks for watching!!