Originally Posted by slimjim8201,Jul 15 2006, 01:45 PM

These two kits make an interesting comparison. The big advantage of the Lovefab kit is that it can make the the same power as the InlinePro kit, but with less boost pressure. But who cares about boost pressure? If both kits make the same 350 wrhp, they will both be equally fast. It may take the inline kit a little longer to reach that 350 rwhp due to the added spool up time necessary to reach it's boost level, but in the end, its the power you look at, not the boost.

Boost level is directly related to head efficiency, turbo selection, intake design and probably most importantly...turbo manifold design. If you held all variables constant with the exception of the manifold designs (the only fundamental difference between the two kits anyway), you could make JUST as much power with the Inline kit. Sure, it may be running at 12 psi instead of the Lovefabs 8 psi, but this is only half of the story. The boost develops based on a LOT of factors, one of which being exhaust back pressure and how efficiently the manifold can flow exhaust gasses.

If you measured the manifold boost pressure AND the turbo manifold pressure, you would find that the pressure delta across the engine would be almost identical at a specific power output. This assumes a number of things like similar tune, etc...

I think a lot of people think that the Inline Kit @ 12 psi is going to be more stressful on the engine than the Lovefab kit @ 8 psi. This is almost certainly not the case.

If you take a pipe, apply 2 psi on the inlet side and hold the outlet constant at an ambient pressure of 0 psi, it will flow a specific amount of air. If you bump of the inlet pressure to 4 psi and the outlet pressure to 2 psi, it will flow the exact same amount of air as in the first scenario. The same applies to an engine head. Power is more or less based upon how much air you can get into the engine.


There are disadvantages in the Inline Pro kit. Obviously, the manifold does not flow as well as the Lovefab. This is evident in the higher boost pressure necessary to reach the same level of power (which means there is more pressure build up in the turbo manifold). This equates to longer spool up time, as it requires more manifold air flow to reach the desired boost level. Once there the boost level is reached, however, it would perform virtually the same as the lovefab.

The other disadvantage is in the nature of the incoming air. Due to the higher relative pressure of the manfold air (relative to ambient) the fuel air mixture will be more prone to detonation. This means the tune cannot be as aggressive as the Lovefab. A few paragraphs above, I assumed the use of a similar tune. If you tuned to take advantage of Lovefabs ability to support a more aggressive tune, you could unlock quite a bit more horsepower. Then you would have to up the boost even more on the Inline Pro kit to achieve that power (which you have already done....8 psi versus 12 psi). Well, now the pressure is even higher than it was before and the tuning window is even smaller now and it takes even longer to spool. See the problem?

It is entirely possible to be making HUGE power with each kit, but you would have to go to race gas probably 50-100 horsepower sooner with the Inline Pro kit.

At really low boost levels, I think it's a toss up. Both kits are safe, one is little more expensive, one spools a little slower. Flip the coin...

Originally Posted by cpoz,Jul 17 2006, 09:35 AM

Stock internals(just springs, retainers, guides). Inline's head gasket, and 15lbs.

Originally Posted by geists2k,Jul 17 2006, 06:39 AM

Just curious, why did you upgrade the springs, retainers and guides? Did you raise the rev limit?

Originally Posted by cpoz,Jul 16 2006, 10:21 PM

I'm running 436rwhp on pump gas and a Inline kit, daily driven. I would say go Inline Pro, but it's just my $.02

Ya, thanks for taken care of the 300c that day...

Originally Posted by Spoolin,Jul 17 2006, 10:00 AM

But if you are leaving you engine stock, you can't run 12 psi unless on race gas all the time, if you want to pay the prices.
If you leave your engine stock and no HG or anything, most people would limit the engine to around 8 psi which is very safe on our engines. That's why the lower boost and more power is much better than trying to run higher boost to get there.
I was just making a point.