Initially, on the dyno, I could only boost to 10psi and it would drop immediately to 5psi. Tested for vacuum leaks and found none. Tightened the belt and it will boost to 13psi and drops to 10psi.

On the street I'm able to boost to 13psi and maintain it there.

I'm planning to get a better belt by gates. Yes. Belt. It's a mp62.
Also plan on changing the clutch. On the street sometime the clutch will slip.

Any other reason or suggestions to keep my boost up on the dyno?

 

dynojet?

 

Obligatory: install turbo.

 

Belts, lol.
Dynojet, lol.
Fail, lol.

 

Car wasn't running right so dynojet to get it running was fine.
Why knock on the supercharger when it makes more power than some turbos w/o the lag?
Making this my daily so a supercharger would be more fun driving to work.

 

That's a very bold statement.

You better have proof to back it up.

 

I've seen some turbos under 200whp/200ftlb.
So yeah. I have proof to back it up.

 

You have back to back dynos of an MP62 vs a turbo setup with the turbo making less power? Go ahead and post them up. You're making statements that will get you in deep waters around here, because they're nowhere near true.
The only supercharger setups that can hold their own against turbo cars are very heavily modified ones. Most those guys are on here, and most of them know what it takes. I don't think you do.

If you like your setup and enjoy it that's all that matters, more power to you. Just don't start pissing contests unless you're ready to back them up.
/threadjack

Back to your question: I think the clutch slip may have contributed to your boost issues, though usually people experience the opposite and see more load on the street resulting in slip.

Since the jet is not a load bearing dyno I don't think that's your issue. Clutch slip or belt slip maybe

 

Why do I need back to back vs a turbo?
I'm just looking at what some turbo guys posted as their dyno result.
I'm not boosting at 18psi. I'm not saying all turbos. I said some.

What kind of heavy modification to supercharger are you referring to?
I'm no expert so please enlighten me. I'm always looking for more power.

For now I just have some mild head work, mp62 ported by Gary, smaller pulley, crank overlay. Don't refer to my sig. That's outdated.

 

Because unless the dynos are the same, and the temp/elevation/etc is the same, comparing some random dyno of one vs the other is completely useless.

See Nitrodanns gt2560 record thread for a perfect illustration of that.

I know what you meant: you're talking about smaller turbos at low boost. But then even a 2554 or 2560 setup on about 10-12 psi is making 220whp with even the most basic tune, and makes plenty of torque under curve on a 1.8. That's why its no comparison: the charger is almost tapped out whereas the most basic turbo setup is just getting started.

The more advanced setups I referred to are TNTUBA, codingparadox, and a handful of others making 250+ and a ton of torque. Those are running fully built engines, lysholm/twinscrew/etc, fancy IM's, etc.

Maybe I missed it: what is your car making now?

My latest miata will be ready soon, if you want to get together and see how they stack up against each other I'm only 1.5 hours away

 

Slipping down to 10psi, hoping to maintain 14psi.
Currently, 209/209.

Hoping to make 250+ and a ton of torque.

 

thats not bad at all.

post up plot when you can