with more of us starting to run bigger turbos, this subject needs to be addressed. on my setup, it doesn't start *** hauling mod untill about 4500rpm. what are somethings we can do to reduce spool?

everyone knows the better flowing exhaust the better. i plan on porting my turbo exhuast houseing, that "should" help a tad, i hope. but is there anything else to do?

does charge pipe diameter affect spool? intake going into the turbo? port out the exhaust ports/mani inlet? anything worth doing?

 

anything that has to do with air getting into/out of your engine effects spool

 

Smaller turbo LOL.

Anything that improves VE in the RPM range in which it spools. In your example, 3500-4000 RPM. For example, cam timing changes that improve torque in that region.

And advancing the exhaust cam so it opens earlier.

 

A 50 shot would wake it up

 

after feeling the jet thrust up top, that is not an option

 

make it rev to 9k...that'll make 4500 seem relatively low RPM...

 

What's your peak power?

BTW I've had a turbo miata since 1998. You?

 

Intercooler with less pressure drop
cam/ignition timing
fuel
manifold design
exhaust design
intake design
improved efficiency

have fun.

 

Are you saying that the boost doesn't start a steep rise until 4500? OR it doesn't hit target until 4500? If it's the latter- that's pretty good spool for a decent sized t3/t4 on a 1.6 IMO.

You need to find out what exact specs are of your t3/t4. Smaller ARs are a relatively simple way to change spool- and smaller is cheaper in the world of t3/t4... especially on t3. You could even go as far as putting a big t3 compressor on.

 

also, the people who like the jet thrust feeling at 4-5K, would probably also like the same feeling at 2-3k

 

Head work is the biggest thing you could do. (reducing spool doesn't sound right, don't you want to increase it?) Porting makes a huge difference when done right and will add power everywhere and help spool and increase the usable rev range by increasing VE at the higher RPMs. But you'll need a book or two on porting to know what to do.

 

Having a dp like that should help.

 

I'm not sure why pics on the shoremotorsports server require a reload to show. :(

 

when you say "porting my turbo exhuast houseing" what exactly are you talking about? Hopefully not the wastegate passage

 

porting is common in the dsm crowd, basically the inlet of the turbine housing and exhaust manifold are opened up/matched

 

How bout we just call it "improving spool"

 

How bout we just call it "Lowering Boost Threshold"

 

Pshhh (pun intended), you wouldn't know what boost is. From the south we call it "makin' her get on down the road".

 

this thread sure did bomb. but i am reaching full boost about 4500rpm.

 

Gain 10-25% more power and drop spool 500-1000 RPMs.

http://books.google.com/books?id=283...um=1&ct=result