Ford Focus Forum banner

1 - 20 of 31 Posts

·
Registered
Joined
·
427 Posts
Discussion Starter #1
just dyno\'d a Vortech

I am running
2000 ZX3 Focus JFA8
Vortech HO supercharger
JBA Race Header
JBA Flex Pipe
MBRP Exhaust
Motorcraft 22C plugs
Nology wires
Royal Purple Oil

With no cat., I only ran 6-7lbs of boost

Dyno'd @ 178.6 hp and 158 ft lbs. @ the WHEELS

You lose 2-3lbs of boost with no cat.
So I ordered a CFM 5.7 crank pulley, will do 10lbs soon.
 

·
I change diapers now
Joined
·
14,444 Posts
Re: just dyno\'d a Vortech

Non-Intercooled right? Who did the tuning?

Nice numbers.

- Drew
 

·
Registered
Joined
·
993 Posts
Re: just dyno\'d a Vortech

it says HO kit, so that's the intercooled version.

My HO kit, with SCT tune done by myself, stock everything, including exhaust except for the supercharger was getting 191HP and 182ft-lb torque on 91 octane.

those numbers seem a bit low
 

·
Driver > Car
Joined
·
23,988 Posts
Re: just dyno\'d a Vortech

you shouldn't lose any boost without the cat.
 

·
Dyno Queen
Joined
·
7,859 Posts
Re: just dyno\'d a Vortech

it says HO kit, so that's the intercooled version.

My HO kit, with SCT tune done by myself, stock everything, including exhaust except for the supercharger was getting 191HP and 182ft-lb torque on 91 octane.

those numbers seem a bit low
Low? Yes, but normal for 6psi.

Check for belt slippage, you should be seeing 9+psi by redline.
 

·
Registered
Joined
·
993 Posts
Re: just dyno\'d a Vortech

you shouldn't lose any boost without the cat.
but he does have a full race header/cat back, etc... so overall, boost could drop a bit due to the added efficiency on the exhaust side.

I still haven't installed my boost guage, so I'm not fully familiar with when the car reaches max boost... I only know that the exhaust would shift the RPM where max boost is reached higher (and actually making more HP at 7psi, than mine at 10psi would). If the redline comes soon enough, max boost may never be reached.
 

·
Driver > Car
Joined
·
23,988 Posts
Re: just dyno\'d a Vortech

the added efficiency of the exhaust should have zero effect on manifold pressure overall. this is a belt driven system. sounds like a boost leak.
 

·
I change diapers now
Joined
·
14,444 Posts
Re: just dyno\'d a Vortech

the added efficiency of the exhaust should have zero effect on manifold pressure overall. this is a belt driven system. sounds like a boost leak.
After I installed my Kamikaze Header(2.5id CO) and 2.5in Full Exhaust I saw a 2psi pressure drop from my old RH w/ 2.25in setup on my JRSC.


- Drew
 

·
Registered
Joined
·
993 Posts
Re: just dyno\'d a Vortech

the added efficiency of the exhaust should have zero effect on manifold pressure overall. this is a belt driven system. sounds like a boost leak.
After I installed my Kamikaze Header(2.5id CO) and 2.5in Full Exhaust I saw a 2psi pressure drop from my old RH w/ 2.25in setup on my JRSC.


- Drew
that's why I figured this could be the case with the vortech kit. Of course, it's a centrifugal blower, but if it means that you would normally hit full boost at 5,000RPM, you might hit full boost at 7,000RPM with the exhaust, etc...

I can't say from experience because I'm still running stock exhaust tho..
 

·
Driver > Car
Joined
·
23,988 Posts
Re: just dyno\'d a Vortech

that's interesting. consider me corrected.
 

·
Dyno Queen
Joined
·
7,859 Posts
Re: just dyno\'d a Vortech

I never saw any boost level changes with various exhaust setups on my vortech'd car.
 

·
Registered
Joined
·
2,741 Posts
Re: just dyno\'d a Vortech

I haven't seen any change in boost with the FS/VF SC when I swithed headers. From FC to FS. There is another focus getting the FS/VF SC here and he has the stock cat and will be getting a header and before we change it out we will check the boost levels.
 

·
9 and 3 Damnit! 9 AND 3!!!!!!!
Joined
·
9,347 Posts
Re: just dyno\'d a Vortech

I haven't seen any change in boost with the FS/VF SC when I swithed headers. From FC to FS. There is another focus getting the FS/VF SC here and he has the stock cat and will be getting a header and before we change it out we will check the boost levels.
fc to fs isnt that much of adifferenc thats prolly why you didnt notice a change
 

·
Registered
Joined
·
1,785 Posts
Re: just dyno\'d a Vortech

I can see overall boost pressures reducing by the larger exhaust, but the comment about shifting max psi from 5k to 7k confuses me because of the fact that any of the supercharger systems are BELT driven so the increase of RPM of supercharger is dependant on RPM of the engine. The higher the rpm of the engine.......the higher the rpm of the supercharger, hence higher boost.

Am I missing something?
 

·
Registered
Joined
·
993 Posts
Re: just dyno\'d a Vortech

I can see overall boost pressures reducing by the larger exhaust, but the comment about shifting max psi from 5k to 7k confuses me because of the fact that any of the supercharger systems are BELT driven so the increase of RPM of supercharger is dependant on RPM of the engine. The higher the rpm of the engine.......the higher the rpm of the supercharger, hence higher boost.

Am I missing something?
centrifugal superchargers can make full boost at less than redline, with excess boost being sent back through the bypass... if you increase the efficiency of the engine, then you'd shift the point where you reached maximum boost upwards in the RPM range, more RPM, more air, more boost.

Just that having a more efficient system will take in more air from the supercharger, and increase the RPM where the max boost allowed by the bypass is reached.
 

·
Registered
Joined
·
1,785 Posts
Re: just dyno\'d a Vortech

So with the exception of the bypass valve (which really is what is determining max psi in your setup) you're original comment still doesn't make sense. You even said it yourself "more RPM, more air, more boost." Take away the bypass valve and the boost is directly related to RPM. So I still don't get what you are saying.

Of course if the efficiency of the motor will allow you to rev to 7k vs. 5k rpms the max boost is going to be higher......as long as you plug the bypass valve. But that doesn't physically change where the supercharger hits max boost, the rpm of the motor is what makes the max psi of the S/C output change. If that same 5k rpm motor could spin to 7k the s/c would output more psi, whether or not the engine could process it is a different story. But you should get what I'm saying.

I know I'm nit picking but partial explanations for newbies wanting to get into FI can sometimes be a bad thing. I'm not trying to say you don't know what you are talking about at all, just want more of a clarification so everyone can benifit from the info.
 

·
Dyno Queen
Joined
·
7,859 Posts
Re: just dyno\'d a Vortech

I can see overall boost pressures reducing by the larger exhaust, but the comment about shifting max psi from 5k to 7k confuses me because of the fact that any of the supercharger systems are BELT driven so the increase of RPM of supercharger is dependant on RPM of the engine. The higher the rpm of the engine.......the higher the rpm of the supercharger, hence higher boost.

Am I missing something?

centrifugal superchargers can make full boost at less than redline, with excess boost being sent back through the bypass... if you increase the efficiency of the engine, then you'd shift the point where you reached maximum boost upwards in the RPM range, more RPM, more air, more boost.

Just that having a more efficient system will take in more air from the supercharger, and increase the RPM where the max boost allowed by the bypass is reached.

The bypass valve does not such thing. Your supercharger makes max boost at redline every time, no argument about it.

Like I said earlier, on various exhaust setups I saw no change in boost. Even running open header, I still had the same boost curve.
 
1 - 20 of 31 Posts
Top