Supercharged SP20 anyone?

[NaughtyGT]

Originally Posted by D-Train

I don't quite agree with your comment there Kaos. Some s/c setups have been know to operate safely with stock internals up to 9 PSI. E.G. MX5 rotrex kit can up the power by 50% to between 130-150kw if tuned. It would only be if you wanted to chase some big power that you'd need to change internals. I can vouch for an MX5 pulling 150rwkw on the rotrex kit on stock internals and it hauls ass

with the risk of offending, running a SC on anything requires strengthened internals if you are wise & expect the engine to have any longevity. Yes, lower boost is one way to counter the higher comp' of stock engine but, the MX5 stock internals aren't that great. The rods are stock.

I thoroughly went down this road about 8 months ago. Found all the info I could before ever considering between the 2 for the MX5. Supercharger or Turbo? This is a debate that will go on for ever & is actually frowned upon on @ least 1 MX5 forum, for risk of severe offense & potential for heated arguments. The subject requires all the information be laid out on the table. I relentlessly searched forums, documentation you name it!

A SC on anything smaller than a 2.0L has one large obstacle to overcome.

It saps power/uses the engines power to operate. What this amounts to is it takes power to make power. Running off the crank it places aggressive load on the bottom end internals.

In simple terms. What this equates to is say you want 125wkw out of the vehicle. You need to allow say, 15kw to be sapped within the crank action.

If you want deeper info then you need to research the facts from experts not just 1 persons application

Btw, alot of SC vehicle owners ditch the SC for a big-ass turbo properly set up. They get the strengthened internals afforded by the SC factory build as a bonus. Factory SC vehicles have stronger internals than a comparable factory TC one due to the stress tolerance differences between the two. A good example can be seen in the MR2 4AGZE engine. Reknown for strong internals. Again, some have opted to swap SC for TC. It's all about application/$$$$/choice.
To be fair, SC's don't need the hassle of oil feed/drain lines & risk of a line blowing & root-ing the turbo etc.

Originally Posted by bourbon

a turbo has to spool up from the engine putting the gasses through...so you get a bit of lag...

this is precisely why a SC requires stronger internals. The turbo is only working hard @ higher revs (above 2500 for arguments sake) whereas the SC places load right @ the beginning @ low revs. Also, you can get a turbo to spool with near negligible lag if you do it right Once it kicks in it can boot like a mule & it's then that it places the heavy load on internals but @ least the engine is already climbing the rev-range nicely

In the end. It's choice. I like both FI applications. As long as they're set up right. Look @ the hell I'm forced to go through with the Merc @ present due to seller having engine built by dodgey half-wit workshop. Basically, they set it up to destroy itself! It was doomed from the beginning & they probably still don't know where it all went wrong. But I do!