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1987 RX Turbo at the drags last night

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Ok, I got my RX to the strip last night for the first time. I moved all of my go-fast goodies from my 86 GL-10 over to the RX. The GL-10 ran a 14.2@93mph last year so I was hoping for that or better in the RX. The best I got last night was 14.3@90mph in the RX (***************footing the worn clutch), it was enough to waste the new Dodge Hemi Magnum. Hah, take that.

 

Aside from the clutch, I was also having issues with my water-to-air intercooler setup, the reservoir ( 1 gallon ) was too small because the icewater in it became hot 2/3 of the way down the track and the ignition retarded to max and then the engine started detonating. I was running a 50/50 mix of 92 octane and AVgas. I knew I should have drained the gas first! I had to turn the boost down to 16psi to keep the holes out of the pistons.

I got it all slapped together 3 hours before the race, just no time to test and tune it all. Plus this thing doesn't have plates so I couldn't test it on the street anyway.

I'm wondering if the dragstrip will let me use spare tires all the way around??? That would give me lower gears and reduce spinning mass and less resistance. Traction still wouldn't be an issue, that starting line is like flypaper man! I have 2 spares already, anyone want to donate 2 more?

 

I'll change out the clutch, get a bigger tank for my intercooler water system and I'm sure I'll be somewhere in the 13's. Then let's see about installing my ported and polished heads and regrind the cams and install that spider intake I have laying around. Oh, and the bigger turbo. I'm still running the stock turbo, some guys in the stands said they could hear it spooling like a mad dog. Yeah, baby!

-Chuck- Portland, OR

87 RX turbo

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My setup:

 

stock verticle throttlebody intake, engine, heads, cams, turbo, fuel injection system and ecu. A/C system and interior still needs to be removed.

 

-home-built steel and copper water-to-air intercooler

-BOV from eclipse, crushed for 20psi.

-Blaster 2 coil

-5th injector mounted right above throttlebody, comes on at about 12 psi. Installing second one to come on at around 17psi.

-home-built adjustable boost controller, cost $10 to build

-home-built 2.5" downpipe matched to turbo gasket for better wastegate flow. no muffler of any kind.

-removed plastic baffle on air box and installed K&N filter.

-20psi autometer boost guage, need to install 30psi one so I can crank my boost up.

 

-Chuck- portland, OR

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holy %$*%*$*hooks batman! I need to do some mods to my wagon, sheesh if you have that little done and you run a 14, I wonder what I could do with that + cams and some more goodies :D

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Yeah, thats pretty impressive, but I can belive it. On my fairly fresh build, I have hit 15-17 psi a couple times.. holy carp that thing really wakes up!

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I put a photo of this setup in the photo album. "Chuck's engine bay"

 

I'm working on a bigger intercooler and a bigger reservoir.

-Chuck- Portland, OR

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hmmm, you think maybe a cone filter might help out a little bit on the times your getting? i know you said that youve taken out hte plastic elbow from the stock box and done a k&n filter, but i wonder if maybe a cone filter would flow better.

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I put a photo of this setup in the photo album. "Chuck's engine bay"

 

I'm working on a bigger intercooler and a bigger reservoir.

-Chuck- Portland, OR

 

Thanks for the pic. Exactly what I was looking for.

 

Is that CIS type injector?

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What RPM are you launching at?

 

4WD Launch I assume?

 

Also maybe we can meet up and check each others cars out since I'm in portland too, I was thinking of going to PIR this weekend....

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The cone style filter might actually reduce power unless I stick it outside of the engine compartment. My Biggest restriction to flow in my setup is the stock turbo and stock heads and possibly MAF sensor.

 

Air density needs to be the primary focus, cold air at medium pressure makes more power than high-pressure hot air. And your engine will last longer too. I will eventually change the filter setup after I make the change to MegaSquirt. I won't be using a MAF sensor so I can use the space to fabricate a filter box that will use the cone syle filter and isolate it from the hot engine compartment. I'll use ABS plastic for the ducting. A cold-air intake made out of aluminum is a contradiction. The heat soaks right through it.

-Chuck-Portland, Oregon

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I'm Down, I can host but I'm actually way out in Cornelius. My car has no plates so I can't drive it to Portland. My wife can BBQ up some ribs or somethin'

 

-Chuck-

 

that is a "cold-start injector" from an 80's VW, they squirt a mist inside the intake right before the starter ingages, they can live with 12vdc all day without damage, unlike peak and hold injectors.

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I checked the A/F ratio with the setup on my last car with basicly the same setup and the stock fuel system goes lean right above 15psi. With the injector coming on around 12 psi, it spikes rich for an instant then doesn't go lean again unil 16-20 psi. It's real hard to tell exactly what is happening with a stock type 02 sensor. You really need a wide-band to get good readings. The plugs give a good indication of what's happening, if you know what to look for.

 

It is not the cleanest fuel curve by any means but it does allow the engine to make a lot more power, cheaply. I'm installing a second injector to kick on around 16psi. That should bring me up to 22psi or so, I hope. I'll have to see what effect it will have on fuel pressure though.

-Chuck-

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I checked the A/F ratio with the setup on my last car with basicly the same setup and the stock fuel system goes lean right above 15psi. With the injector coming on around 12 psi, it spikes rich for an instant then doesn't go lean again unil 16-20 psi. It's real hard to tell exactly what is happening with a stock type 02 sensor. You really need a wide-band to get good readings. The plugs give a good indication of what's happening, if you know what to look for.

 

It is not the cleanest fuel curve by any means but it does allow the engine to make a lot more power, cheaply. I'm installing a second injector to kick on around 16psi. That should bring me up to 22psi or so, I hope. I'll have to see what effect it will have on fuel pressure though.

-Chuck-

 

I'm really interested in this setup. I'm a fool! :banghead: I need to know the details so I can setup something similar. I'm not looking for anything perfect. Your setup will allow me to do what I want to do. I'll go look at your pics.

 

EXACTLY....what parts do I need for the 1 or 2 injector setup? I mean everything? Any instructions on exactly how to set our turbo car up just like yours? I know I'm asking a lot but I don't want to screw anything up and I'd like to get everything I would need to make this work like yours. Thanks!

 

And oh yes, congrats on your 1/4 mile times. That is awesome to say the least. :drunk:

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What parts do you need?

Always start with an intercooler as the first thing. It will make your engine last longer while making more power. A wrx unit is a good one, easy to instal but you need to cut a hole in the hood. OR- a stock subaru water-to-air intercooler.

 

The 5th injector comes from the intake of a nechanical fuel injected VW, like the early jetta, fox, etc.

 

Use your fuel cut-off pressure switch to make it do just the opposite of what subaru intended. Make it drive the injector for more fuel at high boost.

 

Build a home-made boost contoller, Or I can send you one for $15. They work as well as the $200 electronic units, just less bling bling and marketing stuff. I put instructions on how to make it on my yahoo subaru site, SUBARU_18, I'm a co-moderator there, check it out. I made the instructions way easy.

 

The injector get's it's fuel supply from the fuel line right after the fuel filter. The injector has a nice stainless line attached to it, pull that also when you are in the junk yard. The injector has 2 wires, hook it up to a battery to test it, (doesn't matter which is + and -)you will feel a click and you will be able to blow through the stainless line. I tested mine with fuel pressure and saw that it makes a real nice mist of fuel.

 

Just those few mods will make a HUGE impact on performance. The BOV makes gear shifts feel like there is a much larger engine under the hood because it allows the turbo to keep spinning when your foot is off the gas, then BAM full boost when the throttle is opened again.

 

You will destroy the engine if you decide to soup it up without an intercooler.

Hope this helped,

-Chuck-

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This is awesome, I ordered a pressure switch, and my bro back home is going to be hitting the junk yards to find me the injector.

 

 

thanks for the info Chuck

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I'm assuming this is a early '87 with the flapper style MAF, as there is no mention of by-passing the fuel cut.

 

Gary

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