questions about forged rotating assembly

huntco420 · 12-21-2008

Hello, everyone
I have a stock 06 GT I am going to buy a supercharger kit(twinscrew) but I read that I need to replace the rotating assembly with forged ones. My first question is where is the best online place to buy from. What size pistons and compression. I'm going to run 10 pounds of boost. My second question is can I replace the assembly or do I have to have that done. I'm new to mod. motors, but I do have an old school mech. for a dad. This is my first real post, but have been on this site for months. I can tell every member clearly knows what they are talking about and the advise posted is remarkable.

bigwilly43729 · 12-21-2008

You don't have to replace the bottom end to supercharge the car. A good tune and being reasonable about your power and boost levels will keep your car running strong for a long time. Most people try to stay in the 425-450rwhp range. Any higher and you are potentially asking for trouble.

If you do want to change the assembly, you'll want to keep your compression low; around 8.5-9:1, but the particular type of s/c will factor into this as well.

Companies like MMR, Livernois and Eagle all sell quality rotating assemblies.

If you are not an experienced engine builder, DO NOT attempt to replace this yourself.

clfrye · 12-22-2008

There are plenty of us Whipple owners that are running 10psi with the stock internals. The canned Whipple tune is pretty safe. I have been running it for about 16,000 miles.

If you do decide to get forged internals, get a complete kit from one company. All the companies previously mentioned also sell assembled short blocks, if you want to have a shorter downtime. They sell for $4500 - $5000, without shipping.

travelers · 12-22-2008

Bigwilly is right, but if you do decide to look around at some of the engine builders. Livernois, Foxlakeracing, Sutten Highperformance just to name a few. Do some reading at the different sites and ask question. Livernois isn't the cheepest but if and when I need some that's where I'm going.

tw0scoops123 · 12-22-2008

I agree with everyone here. Forged assembly's are not necessary with a basic setup for a twinscrew or most FI applications. As long as the tune is good, you should be fine with everything stock.

kenneth · 12-22-2008

another one agreeing with above: for 10lbs. boost you can keep the stock internals, just make sure you get a good tune.

forensicsteve · 12-22-2008

+1 tune is paramount. Driving habits will have a lot to do with what lasts and what blasts.

**stlwagon** · 12-22-2008

There is no magic number on when your engine will let go. Even with a rock-solid tune, there's no guarantee.

shifter87 · 12-22-2008

I have seen decent sets on CHP and on stage 3 motorsports. It also doesn't always matter if you have the same name on your parts a lot of people have different set-ups do to the fact there are only a couple of actual piston and rod makers and the people selling them change the name somewhat.
Eagle or manley are good choices.