Just like the title states. Looking for any neg. effects of a JR supercharger on a gsr engine.
I know on miata's they tend to cause an idle droop when slowing down. This tends to be worse at night when lights are on and when making turns.

 

Mine has no problem with really low idles, but I have it on a B17 tho.........

 

what type of intake did you end up using with JRSC?

 

Same problem here. Just installed the base JRSC on my b18c1 earlier this month. Idle droops to about 600rpm (give or take), engine slightly stutters, and then goes back up to the expected 750rpm. Mostly occurs when approaching a red light, so I let out of gear at speed, and coast in neutral.

Re-gapped the spark plugs from the stock gap down to about 0.035", but no change.

Will be adding BTC and VPAC after the holidays. Will report if that helps.

 

Are you running a stock flywheel or a lightened one? This can cause the effects to be worse. You maybe able to adjust your idle up alittle to cancel the effects of the blower drag.
On the miata there was a kinda fix. A once way valve was added and a larger vac. line was attached to the intake manifold.

 

Good question on the flywheel. Stock flywheel/clutch. But I also installed an Unorthodox Racing SSc lightened crank pulley. This causes the alternator pulley (and hence the s/c pulley) to be overdriven, which is supposed to give an extra 2psi boost with the JRSC.

Hadn't thought of that as a cuase of the idle droop. BTC and VPAC have been ordered, so I'll try that first. Adjusting the idle slightly higher is something to keep in mind. Thanks.

 

i'd expect the bigger crank would make the blower drag less noticeable.

bigger crank, might be harder for the engine to turn said crank,
but it's easier to turn the sc. and when slowing down the crank, it's bigger, so it'll be harder to slow down too.

just like a flywheel,
when you get a lightened one, your revs drop faster.