SUPERCHARGER

[MANDALAY]

this is the setup of a 1zz with a rotrex supercharger, which i want to mimic, but i want to use a standard airbox and different intercooler.
Looks simple ?

[assassin10000]

Originally Posted by MANDALAY

Now can you over kill ? $ are roughly the same so 255 high pressure on with a FPR ?

The stock FPR has a return and also a vent to the charcoal cansister . Do these aftermarket ones have that also ?

The SC is rated up to 400 HP. MORE CONCERN IS NOT TO OVER BOOST.

Overkill? Not really. It's only 'overkill' if the return is large/fast enough and chokes causing the fuel pressure to be 'higher' than you want it to. Because fuel volume drops as pressure rises.

A/M FPR's have a return, I don't think I've ever seen a return with a vent to the charcoal cannister . Perhaps a vacuum line that gets it's vacuum source from there?

Rated HP don't really mean much to me anymore, its just giving you an 'end' number. I'd ask Rotrex for a compressor map (if not on their website) and work the numbers out for your goals, which from what I gather is a large usable power band that comes on fairly early and lasts until redline .

You might end up going to a larger s/c with a larger diameter pulley to spin it slower at high rpms while maintaining the air volume necessary for your goals... or you could even drop down to a smaller s/c with smaller pulley to get the s/c rpms up earlier, while still having a large enough 'range' before compressor surge (ie:choke point/max safe rpm), and enough airflow to last through redline.

Originally Posted by MANDALAY

http://farm4.static.flickr.com/3225/...a5867084_o.jpg

this is the setup of a 2zz with a rotrex supercharger, which i want to mimic, but i want to use a standard airbox and different intercooler.
Looks simple ?

Looks fairly simple, I don't like the air filter/inlet tube at all though. The W/A cooler setup actually annoys me, even though I'm sure it works. And the MAF positioning seems like a really poor design to me. I'm sure it works, but it's not one I'd run.

I'd run the intake to either an airbox, or another area with some good fresh airflow. With the MAF just behind the filter/airbox just like stock setups. I'd plumb a bypass valve between the piping from the S/C to T/B, and the piping from the MAF to the S/C. That will prevent any monitored air loss issues (engine stumble/dying) with running a BOV on a MAF system.

And I'd try and run a 'cleaner' looking W/A intercooler system, where it's more out of sight. It looks like they just kinda packaged that where they could fit it. And in the MR2 engine bay you might be stuck doing something similar, but that's mostly aesthetics.

Andrew

[MANDALAY]

Our SW20 has more room. The IC will be PWR cylinder design and be b/w the engine and the fire wall under the inlet manifold.
Iam planning to use the factory air box with all the reasonace boxes. Hopefully the std MAF wont max out, then route 3 inch pipe to the SC.
So air box > maf > SC > IC > TB
so the bypass after the IC or before ?
Also in that set up wouldnt the MAF get a better true figure since the temp at the air box maf will show a different temperature after the IC making tunning a bit skewed

[MANDALAY]

BTW yes on the RED top does vent to the Canister . The black stop doesnt have the fuel regulator on the fuel rail its next to the fuel pump.
Rotrex has the compressor maps on their site
The BOV , does it require a vacuum line ?
Under the inlet manifold there is a 3 mm nipple that just has a rubber stopper. Could that be a source for the vacuum ?
Man even with the EPC AND MANUAL there is no reasoning why its there ? Is 3mm opening big enough

[assassin10000]

Originally Posted by MANDALAY

Our SW20 has more room. The IC will be PWR cylinder design and be b/w the engine and the fire wall under the inlet manifold.

So air box > maf > SC > IC > TB
so the bypass after the IC or before ?

Also in that set up wouldnt the MAF get a better true figure since the temp at the air box maf will show a different temperature after the IC making tunning a bit skewed

Ah, I agree the cylinder design will definately package nicer in there. The bypass should be after the I/C, IIRC the closer to the T/B the better.

No the MAF won't get a better 'figure' or readings when after the S/C. It's designed for air flow @ regular atmospheric pressures. IMO thats a stupid way of doing things, basically a bandaid for those that didn't/couldn't figure out that you need to straighten airflow before it goes over the MAF sensor.

Originally Posted by MANDALAY

BTW yes on the RED top does vent to the Canister.

The BOV , does it require a vacuum line? Under the inlet manifold there is a 3 mm nipple that just has a rubber stopper. Could that be a source for the vacuum?

The FPR vacuum line may go the cannister. But I think it's just using the cannister as a vacuum source. And not as a vent.

Yes both a BOV & Bypass valve require a vacuum line from a source behind the throttle body to actuate the diaphram (so they'll work when the t/b shuts and the pressure differential behind & before the t/b causes the diaphram to open and blow off/bypass). 3mm opening should work, it'll take a standard 5-7mm vac hose due to the nipple size won't it?

Andrew

[puretone]

Originally Posted by MANDALAY

BTW yes on the RED top does vent to the Canister . The black stop doesnt have the fuel regulator on the fuel rail its next to the fuel pump.
Rotrex has the compressor maps on their site
The BOV , does it require a vacuum line ?
Under the inlet manifold there is a 3 mm nipple that just has a rubber stopper. Could that be a source for the vacuum ?
Man even with the EPC AND MANUAL there is no reasoning why its there ? Is 3mm opening big enough

yeah i was about to post that, our RedTop has a little tube running to a little solenoid that in turn runs to the canister, now I think what is happening there is it is sucking the fumes from the canister?
I think mine's source was at the TB:
throttle-body <hose> solenoid <hose> canister

I'll have to review it when I get back to the car...

[MANDALAY]

There is 2 . One from the TB and the other from the Regultor that go to the canister.
Hey man have a look at your celica manual and see if there is a diagram because there is on in the MR2 manual

What i think is happening is is the regulator has a fuel return and that other vent is to the canister to relieve any pressure .So as not to vent to the atmosphere. seams logical. Then the relay on the canister shuts that line when the engine is running.
The bottom of the canister also has a return to the fuel tank. This way its totally sealed , EPA.
I always have wondered if people are not getting full power or problems because of things left of from the original design/ layout ?
One thing for sure l have everything on and factory bar 4 items
lightened fly wheel
TRD air filter
Different clutch
Remus exhaust

[MANDALAY]

Please any one who doesnt have their beams in their car.
What is the diameter of the pulley on the crank that belts up to the stock mr2 alternator or the Celica's power steering pump.

[Roman]

MR2 one has large diameter on all pulley sections, celica has one pulley smaller than the other...

I can take some pics and measurements for ya over the weekend if you like, I've got a celica one but had an MR2 one on my last motor.

I dont think a small belt is gonna be enough to run a supercharger without slipping though.

[MANDALAY]

Cool. The inner pulley will run the SC so its diameter is used to calculate the pulley diamter for the SC for a given PSI. I will be putting a tension idler , probabley the same one that is used on the cam belt . Need further investigating

[assassin10000]

Originally Posted by Roman

I dont think a small belt is gonna be enough to run a supercharger without slipping though.

A good belt with the right tension should be fine for a low boost setup. The several jackson-racing setups I've dealt with in the past on honda's all used the stock alternator belt (4 rib wide). Running anywhere from 6-10psi, with no issues. (except one that was out of alignment and threw a couple belts until we realized a spacer/washer was missing)

Granted, a wider belt would be 'better'. But it might not be necessary.

Andrew

[MANDALAY]

I also want to add a belt tensioner, idler.
Any toughts ? As ive seen some Jackson-Racing setups also have them.

[assassin10000]

Originally Posted by MANDALAY

I also want to add a belt tensioner, idler.
Any toughts ? As ive seen some Jackson-Racing setups also have them.

Build the provisions for the idler/tensioner into the s/c bracket if possible.

Similar to a Honda Civic D-series A/C compressor tensioner. (hell, you might even be able to adapt one of those to work!)

Andrew

[MANDALAY]

^ hey buddy any chance you can find a picture of one ?
Well its good news Found insurace company to cover a SC modification
Start working it.
Question one tuner says MAF the other say MAP. In short form what do you guys reckon is the better approach ?
Also was told that in the MAP set up i would loose the Knock sensor > This isnt a good thing

[assassin10000]

Originally Posted by MANDALAY

^ hey buddy any chance you can find a picture of one ?

Question one tuner says MAF the other say MAP. In short form what do you guys reckon is the better approach ?

Here's a pic from the service manual.

It's basically a bracket, which has a pulley & bearing on a post that locks in place on the bracket. With an adjusting bolt to tension by raising/lowering the pulley/bearing.

MAF or MAP will work, whatever you feel is easiest to get passed 'engineering' is what I'd recommend (although I prefer MAP, if only because it'd make for a 'cleaner' setup/install)

Andrew

[MANDALAY]

Thanks . We have them also on Toyota's but i thought foer the SC you needed a set up with a spting load ?
I want to try the stock MAF first, If it max's out then try the Turbe Supra one . The have had success with that one. Must be higher setting ? due to the fact its already on a turbo engine. If all fails the MAP. wHAT DO RECKON ?

[puretone]

i figure MAP works better with boosted engines bc it actually 'reads' boost....and since all modern-day diesel trucks run MAP's that must mean they are pretty good'n'reliable no?

I'm gonna have a look at the ST202 CD MANUAL now MANDALAY and see what I come up with....I'm starting to think I might have one of mine attached wrong, I noticed a surge in throttle way back when....thought mine only had one vac to that solenoid...

[assassin10000]

MAF does a better job of reading actual air 'volume' going into the engine. MAP does a better job of how much air is pressurized within that system after the compressor. Truthfully with as good as technology is now both are good systems, it just comes down to the tuning. That's is why many of the earlier fuel injected vehicles ran a MAF or AFM instead of a MAP sensor to meet emissions standards at first. Now it's pretty much a non-issue.

You can actually use both at once... (Just requires a lot more time figuring out the tuning.) Case in point, the Nissan S14 SR20DET uses both a MAF sensor & recirc valve WITH a 'boost' pressure sensor reading off the intake manifold....

Andrew

[puretone]

Originally Posted by assassin10000

MAF does a better job of reading actual air 'volume' going into the engine. MAP does a better job of how much air is pressurized within that system after the compressor. Truthfully with as good as technology is now both are good systems, it just comes down to the tuning. That's is why many of the earlier fuel injected vehicles ran a MAF or AFM instead of a MAP sensor to meet emissions standards at first. Now it's pretty much a non-issue.

You can actually use both at once... (Just requires a lot more time figuring out the tuning.) Case in point, the Nissan S14 SR20DET uses both a MAF sensor & recirc valve WITH a 'boost' pressure sensor reading off the intake manifold....

Andrew

i noticed that in the countless modding magazines i splurge on....do you happen to know how that plays out in the ECU/tuning? Different injection maps for either sensor? Or combo reading?

[Roman]

Probably uses MAP as secondary feature, ie. to give it fuel cut at 12psi or something.