When are you guys shifting? I did some searches and didn't find any in depth info. 3500rpm? Also what Engine/Turbo combo?
Shift points
- Thread starter nmband13
- Start date
Since it is in the drag racing section I would say 1/4 mile....
I think a lot of it depends on valve springs/ last time you checked the lash-too much will float them. Also depends on how much risk you want to take (i.e. how much buffer you want for input shaft breaking etc.)
I think a lot of it depends on valve springs/ last time you checked the lash-too much will float them. Also depends on how much risk you want to take (i.e. how much buffer you want for input shaft breaking etc.)
What buffer are you referring to, for input shaft breakage? Is there a thread about it i can read?
Not that I know of. if you break your input shaft you are going to over rev. how far you over rev depends on what you have the limiter set at. Just something to think about when setting it
edit-I really don't have numbers to throw out. seems like a lot of it has to do with floating valves
edit-I really don't have numbers to throw out. seems like a lot of it has to do with floating valves
Nope I'm playing with fire lol. If she gets hurt its my excuesse to the wife for a built motor to go play in the 2.6 class or 3.0 class. she will just think its a rebuilt stock motor lol:roflmao:
If your drag racing the ideal shift point will keep near peak power. Usually that would be at to 100 rpm's above peak HP. It will very with each particular engine combination. The more fuel and air that you have at disposal the higher that point will be. For instance with 45 overs and a S300 66 that number was shifting at 3400 rpm's. If you are sled pulling then wheel speed becomes very important so you turn the motor harder. Hope this helps you with figuring what works best for you.:thumb:
I run 3800-4000 sled pulling and tried 3900rpm drag racing. When drag racing it doesn't hit 32psi til 5th and otherwise it runs 26-28psi 1st-4th.
Stock Turbo w/ BatMoWheel and 60% Injectors is my current setup.
Stock Turbo w/ BatMoWheel and 60% Injectors is my current setup.
My race tune shifts at about 3800, billet S475, stock valve springs. Feels like it could pull a couple hundred more and still be in the power but I feel I'm pushing it now.
The limiter doesn't do beans when you snap something in the trans. Unless maybe you kept in it and let it catch itself. You can see right around 5k within a couple frames in a log when it breaks. Not that I would know :rofl:
I always figured if it was set at 3500 vs 4200 it would keep it a from over reving as much, but yea she is going to over rev. I was having issues spinning in 2nd and 3rd gear but didn’t want to raise the rev limiter way up b/c of this. Guess if you are going to let the valves get friendly with the pistons it really doesn’t mater that much. I'm sure one day Ill find this out too...