montelibre wrote:Thanks for the replies Jeep´s Jake.
Does the roof weakened by lowering the piston material?
I want to run with a 6psi.
8 psi I think a lot, knock the engine?, Does your engine a stock 4.0?
The final question I can not translate into my language, I do not understand.
You could run 6psi of boost safely without lowering the CR from 9.6.
With the right timing you can do a lot. Like mentioned above, 6 psi could be fine depending on your set up. What fuel injectors, timing control, and fuel octane will you use? Does that supercharger kit come with a fuel pressure Regulator? I run slightly higher compression than stock (head surfaced flat, chambers polished, Mopar Performance head gasket, and a 68-232-4 comp cam - the calculator has it at about 8.9ish) Other than that, I run 89-91 octane, 2 heat ranges cooler spark plugs, 36# injectors, and an FTC-1 from Split Second. Boost is amazing, even on a mostly stock engine. You'll be happy with it.
I have a request a Splitsecond FCT1-019B. I worked with 32 lib/hr injectors. The fuel octene is 95 or 98. The header is a Paccesetter with a flowmaster 40. The Cam is a Elgin, I don´t know the characteristics.
The pistons, I yet to answer me 505performance.
What worries me is how to lower the C.R. for the engine to have no risk.
Thanks.
With that octane you will be way ahead of most of us in America already! And for compression... I could tell you more if I had built a motor, but unfortunately I can only tell you what I have so far. But between the fuel you have, and the timing retard feature of your FTC you should be just fine. On my "low" octane 91 I'm still running close to stock timing even at max boost. Ive pulled out enough timing to run 87 before, so I know it works. It might be better to have the extra compression available, and just adjust timing... Food for thought anyway. Pulleys are another option.
That is a 3.2" American Supercharger modular pulley. It run at 2.7 psi, very low. I have a 2.8 pulley (barrowed from a friend), it run at 4.5 psi and it works great. In this time I hope to lower C.R. to install a 2.6" pulley and reprograming with Split second FCT1-019B...
If you ran 4.5 psi without any detonation then I would try running the 2.6 just to see. You will keep your naturally aspirated power and still have the boost. You can easily stay out of trouble if you just test it carefully and listen for any noises. And you would save alot of $$$ and time too. The trend in car magazines lately for positive displacement blowers is to build a good compression motor and run a small (up to about 10psi) amount of boost for the best power. You might need to machine the snout to fit the 2.6 pulley too... I had to on mine, but it was much older than yours.
