Though I am the other guy with the Rotrex, its not my thread. I was convinced to "go turbo" a long time ago

 

I know. I was responding to this.

He asked for it.

 

The rotrex is good for medium-power builds. For a built motor, you cannot beat what the 6258 will give you.

I like what I have, it does what I need it to do, and I have zero fussiness with it. It is reliable trackday FI for me. But when this motor goes, I will be going EFR 6258, or its descendant - might be 5 years for me.

 

I'm feeling quite convinced honestly. The cost difference is the only deterring factor for me. Still looking at another $4k to get the engine finished and in the car (including some extra goodies) which is looking like the light at the end of the tunnel.

but to spend another $4k on boost feels like more tunnel

Whats the consensus on running 10.5:1 compression with turbo? It was chosen mostly the combat the rotrex's inherent flaws, but with obviously limited timing and boost would it still be feasible? time to pour through build threads

 

depends on your fuel

 

Would 91 be a major limiting factor? I'm not opposed to going e85 in the future but I'd like to have some fun with it until then.

 

yes. very much so

CA 91 is one of the worst pump fuels available.

 

I'm talking to a buddy of mine who works at JE pistons about getting a set of 9:1 pistons. Good thing I held off on assembling the shortblock!

 

To be fair

 

Valid point, but this is a street car right?

Seems like the OP would benefit from the red area...

 

hence my "I guess if you were building a race car that plot would be acceptable, but man my 1.6L makes more torque than that for the majority of the powerband," comment.


also to be fair, my car has never felt more slow than when I had this powerband:

 

that red area FEELS SOOOOO GOOD MAN!!

Seriously. People don't even realize it until they drive cars with those 2 powerbands back to back and their mind is blown.

 

wait wait wait no no no... in that green area, the Turbo car is STILL making more HP AND torque than the rotrex build. the fact that the rotrex is making more HP than TQ doesn't matter since the turbo build is still higher in both areas. there's not a single place in that rotrex powerband that would be stronger than the turbo. On the graph it shows that under 3.5k rpm the rotrex would be better, but I'm not sure that's accurate (not sure both were being properly measured at that rpm).

 

obviously not since 1 pull starts at 2600 and the other at 3200.
if both started same time it would be EVEN better for the turbo and would make the rotrex look even worse

lol

 

yeah, because that's where the rotrex is finally making the same amount of boost that the turbo has been providing since 3500RPM. Under 3500RPM the turob was still better, you're looking at where the turbo HP crosses the Rotrex TQ.

Driving in the above turbo car, is such an insanely sick feeling of speed. Sure after you get into taller gears the rotrex will feel the same, but around slow corners or on the street there's no comparison. Plus I wouldn't want to drive that rotrex setup on the street considering how much work most have been done to achieve it...the car would not be street friendly at that point.

 

Has any of the pro-turbo camp driven a proper Rotrex setup? I would assume that there is more to it than just the torque numbers.

 

sure there is, there's also the ease in driving a real slow car around a corner.

 

Touché!

 

How would you know it's easy?

 

because it's slow.