2007 The Quest For 9's Naturally Aspirated Has Begun!!!!!
First of all, I want to thank Jim Monson (Monson Racing) for all the help, and patience over the past couple months, as well as for convincing us to build our own engines. If not for his knowledge and willingness to share that knowledge with us, we would not have even thought about taking on such a project!!
More Camshaft, More valve train stability, lightened valve train, More Carb, Stiffer pushrods, More Vacuum, and More RPM are the things that have been added for this year. The car still weighs in at 3000 lbs with driver, so the weight savings will have to wait another year.
Last years concerns:
One of the biggest problems we have had with the car is the launch and after speaking with some very experienced pure street racers, it seems as though the problem may have been in the RPM at which it came of the 2-step. This year we will be trying their advice of launching the car at 7000 RPM on the 2-step and possibly going higher. Basically what ever it takes to get the car to leave correctly. **Side Note** After the disappointing tear down, the lauching problems may have been caused by other things besides just the RPM.
The other problem was how loose the suspension was. This year we will be starting with the suspension fully stiffened up to try and keep it from wheelstanding like a monster and then keep the tires planted on the ground in between gears. Supension limiters will be added if this does not correct the problem.
Now that all the engine related problems seem to have been addressed, the next possbile area of concern is the clutch and flywheel. After speaking with Matt @ SPEC Clutch, he has assured me that if the Stage III / Steel flywheel does not get it done, there is another option. From what I understand, the next step is a hybrid Stage II / III+, with an Aluminum pressure plate. We will see what happens here shortly.
Details of changes for this year:
Heads:
- AFR 205cc (Same as last year)
- Flat Milled .015"
- New Chamber size 57.5cc's (Obviously they were not exactly what AFR advertised them to be)
- New Ferrea valves (2.080" / 1.600")
- New flow numbers (Flowed on a 4.040" bore at 28" without a pipe on the exhaust)
Valve Lift Intake Exhaust
.100 77 67.5
.200 145 123
.300 206 169
.400 256 197
.500 294 208
.600 314 213
.650 314 214.5
.700 313 216
.800 290 216.5
***********SEE GRAPH BELOW************
Camshaft:
- Straightline Performance Custom Grind
Valve Train:
- K-950 Valve Springs 1.550" diameter, 1.970" Installed height, 295lbs seat pressure, 700lbs open pressure
- K-7320 Titanium retainers
- Hardened I.D. locators for springs
- New seals (threaded to prevent them from walking off)
- Smith Brother's 3/8", .120" wall pushrods, 7.050" Long (Very accurate product - less than .001" variation between all 16 pushrods)
- Isky adjustable 3/8" guide plates (these were so much fun!, so much that if there is one issue with the rockers, be it adjustment, alignment, what ever......They are coming off and Shaftmounts will be going on!!)
Head Gaskets:
- Fel-Pro 1011-2 gaskets 4.100" bore, .039" compressed thickness
- Quench height will remain .044" with pistons .005" in the hole
Compression ratio:
- 12.6:1 (Not quite as much as we had hoped for, but the difference in power will be minimal)
Carburetor:
- New Pro-Systems 4150 Pro Series carb 950 cfm (actual flow = 840 cfm)
First couple of passes made for 2007 with no tuning! There are definately some 9 second passes coming!!!!!!
Here are a couple pics from the MM (Motown Muscle) race.
Last pass of 2007.........
10.17 @ 134.9 Naturally Aspirated!!!!!!!!!!!!!!!!
