Quote:
Originally Posted by PRAY
Sorry, I though I was being clear. I was asking for which pump, injectors, lash cap, cam lobe etc. I am very familiar with the LS motors and I am getting more familiar with the LT motors. Just wondering if there was an easy GM alternative or additions that is an over the counter "bolt in" that has been proven to deliver enough fuel for 750rw. It seems I am reading that the LT4 pump and injectors with a lash cap will do it. I will have to do a cam swap for the power I want to get anyway so the up sized lobe seems like a no brainer. I do think that 650rw should be pretty easy with boltons and boost though but like stated above, we are limited to 560ish rw in these cars unlike the C7's. I have also read that our fuel lines are to small as well. Not sure if there is any truth to that.
Thanks for the link, I am going to give it a read through.
|
The 550-560 RWHP is a limit inflicted by fuel system and pump gas. You can'y go really rich with the fuel system due to capacity you can run at MBT (maximum brake torque) timing because of low octane pump gas and and 11.5 CR. The LT4 has a 15% higher capacity fuel system and only 10.5 CR. that allows it to run higher output on pump gas.
Run a mix of race gas (like 109 unleaded) and you can set the A/F ratio up to best power and bring the timing up to MBT to make more power. We were making over 610 RWHP with a Maggie Heartbeat @ 7.5 psi boost on an A8 with the stock fuel system in this configuration.
I'm not a fan of straight methanol injection - had a dyno fire with methanol once, had no idea the cell was even on fire until the stuff started melting off the walls of the dyno cell. Never want that in my car - especially stored under the hood in an unsealed plastic bottle. People are running straight methanol as a band-aid for the LT1 fuel system but the safe fix is adding a bigger fuel pump and injectors as required.
We have just started testing with water injection (<50% meth-non flammable). Water is really what you want anyway, it has the anti-detonate properties that are beneficial to making power on low octane gas. I know that everyone can easily see the inlet air temp decrease with meth, but water controls detonation inside the combustion chamber. I've had great results with straight water, but if you live in a cold climate you need the methanol to prevent the water from freezing.
New LT1 fuel system components are already starting to show up on the market, pumps and injectors, which are what you'll need to make the power you're looking for.