SN2000 HO installed on 406 SBC
Thank you to those who answered my questions.
I got to a point in the installation of the SN 2000 where I could take it for a spin.
Back ground on the Car and Engine:
1972 Olds Cutlass
TH400 (low gear set) and 3.90 rear gears. Est. 3650lbs with driver, car was put on diet.
Engine:
406 cu. in. Small Block Chevy
9.6:1 Compression ( Forged SRP pistons)
Edelbrock Performer RPM heads
Howards Hyd. Roller cam, 230/232 Duration @0.050, 0.510 Int. 0.530 Exh. Lift, 112 Lobe Sep
3200 Stall converter
Previous best E.T. NA was 12.41 @ 106 MPH, 1.66 60ft on drag radials (AFR 12.3 with 33 degrees of timing)
I installed the blower and took it for a test run down the street. Wow, lots of pull in the mid range. Makes 5psi instantly and holds well past 5300rpm (my shift point). AFR is in the 10.72 to 11.72 towards the upper RPM. No third gear pull, so can’t say how it will really work until I get it to the track in June.
I backed the timing down to 23-25 total, put in colder plugs (0.038 gap)
Blower is a SN2000 with the HO impeller and 34-35 in/lbs of turning torque with seals in. I have 75% plus belt rap with a 4.5” (4.35 on the ribs) blower pulley and a 7”(on the ribs) crank pulley. Shift point normally around 5,600 max (shift light set @ 5,300). I have a cooler, but it’s not installed yet. It will be before I drive it to the track.
I made the brackets and collected misc. parts to build my own blow through kit. Mind you the pictures are of it installed, but I have some more finish work left to due on it.
I’m hoping to pick up 5/10ths, I would really like to run a 11.99.
I though I would share this with folks. I know most of you are Mustang guys, and thought that some others might be interested in a non Ford application. Nothing wrong with the Fords or Mustangs, I like them too.
Check my Album for pictures.
Any advice on tuning would be great or other suggestions too. Issues I’m over looking? Thank you all!! This forum is great.
No 11's yet, but interesting IAT.
Back to the track again. Leaned out the AFR to 11.8-12. Unfortunately it was 100 degrees out, so it went a best of 12.148 at 109.48 with a small 5MPH head wind.
I did setup an IAT sensor it was showing 180 degree air temp at 7psi through the traps. These things get hot. I wonder if an Air to Water intercooler, like the Vortech Aftercooler design, would help?
FYI: I have a 4.5” blower pulley with a 7” crank pulley and go through the traps at 5600-5800rpm, so blower speed is around 40,000rpm.
2nd gear seems to be slipping so; I will pull the Th400 this weekend and have it checked.
Damn elusive 11 second time slip is irking me!!
BTW: I’m in the market for a VR4 kit or blower if anybody has one they would like to sell.
Update on Air to Water Ebay special
Well I ran the car last night at the track with the intercooler in place( see above pictures). It appears to only reduce the boost by about .25-.5psi through the mid section of the track, but I still saw 7psi through the traps. All in all I would say it cost about 0.04-0.05 of second in the quarter mile.
Intersting, the added pipe and intercooler decrease the intake air temp. The passes I made were with no water in the intercooler, it was just a test pass to see what the restriction would be. However, letting the car cool in the lanes the intercooler seem to work like a heat sink. Normaly I see IAT of 165-180 degrees, but last night the IAT was in the 130-140 range with comparable outside conditions.
The tank for the water is back ordered, I hope to have it before the last race of the season 11/20 so I can test it with ice and see how cool I can get the IAT.
Car still ran 11.95 at 110 with 10.2-3 AFR (I know I need to lean it out)