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BoostedBalls

1987 RX Turbo at the drags last night

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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

 

*sniffle*

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How did you tune the 5th injector to control when it comes online? MegaSquirt?

 

I really, REALLY want to get a fifth injector on my puppy and turn up the boost... man, I can't believe you got more than 15 psi out of the stock turbo... insane man....

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BoostedBalls, I just read your post more closely. I see "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."

 

How exactly do you do that? Pardon my ignorace...

 

Also, what years Jetta should I look for when injector shopping? Are those cars SPFI?

 

EDIT: After reading MattyG's post - so this fuel cut-off pressure switch is not a part that's already on my car? Or - I need a second do to this "reverse duty"?

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EDIT: After reading MattyG's post - so this fuel cut-off pressure switch is not a part that's already on my car? Or - I need a second do to this "reverse duty"?

 

The fuel cutoff switch is a part from the 85-86 turbo cars.

 

If you look on your 87+ turbo car, on the passenger side strut tower, there is a vacuum switch. It comes on at 1psi to trigger the turbo light.

 

The 85-86 cars have 2 switches there one for the turbo light, and one for fuel cut.

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I got a Hobbs-style pressure switch off of ebay. You can set it to a specific pressure (between 4-15psi on the one i got) to activate the electric circuit and then kick the injector on.

 

86_1_b.JPG

I think you can get the gist of how it works by looking at the pic... Once the stuff gets delivered Ill try to get this rigged up and put details.

 

*edit* it was only $15 with shipping

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I got a Hobbs-style pressure switch off of ebay. You can set it to a specific pressure (between 4-15psi on the one i got) to activate the electric circuit and then kick the injector on.

 

86_1_b.JPG

I think you can get the gist of how it works by looking at the pic... Once the stuff gets delivered Ill try to get this rigged up and put details.

 

*edit* it was only $15 with shipping

 

That thing looks awesome. Time to get one, myself! So you plumb it into where the MBC is?

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quick question:

 

Is this:

 

3_2_1030.jpg

 

The same part as "cold start injector"? I keep seeing a part (pictured above) called "cold start valve" but no "cold start injector."

 

Thanks!

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Hmmm... boosted's pic shows a hotwire MAF, and no fuel cut. Iquiring minds want to know.

 

6630engine_bay-med.JPG

 

Gary

I've never got fuel cut, and nobody else who ragged on my car got fuel cut from what WJM has said. I still think it is some ECUs and has a lot to do with how the air is.

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I got a Hobbs-style pressure switch off of ebay. You can set it to a specific pressure (between 4-15psi on the one i got) to activate the electric circuit and then kick the injector on.

 

86_1_b.JPG

I think you can get the gist of how it works by looking at the pic... Once the stuff gets delivered Ill try to get this rigged up and put details.

 

*edit* it was only $15 with shipping

 

This is exactly the kind of device us folks need with the maf voltage controlled fuel cut. We can use this with the extra fuel injector and a HKS fuel cut defenser to get the results we need. Now to shop for an extra injector along with this Hobbs device.

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This is exactly the kind of device us folks need with the maf voltage controlled fuel cut. We can use this with the extra fuel injector and a HKS fuel cut defenser to get the results we need. Now to shop for an extra injector along with this Hobbs device.

its all band aids, bloody band aids I say.

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its all band aids, bloody band aids I say.

 

Whatever works. I'm only concerned about safe cylinder temps, decent drivability, reliability and for everything to work consistantly in all weather and types of racing. If this bandaid can do this, I'm in.

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Whatever works. I'm only concerned about safe cylinder temps, decent drivability, reliability and for everything to work consistantly in all weather and types of racing. If this bandaid can do this, I'm in.

so will a stand alone, with better injectors. and you'll be able to make more power. but if the band aids work for you go for, for me they would be a waste of money.

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while i obviously stand behind the standalone setup.. with my stock injectors.

a well thought out band-aid setup is better than nothing at all

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you guys think a similar band-aid would work with a td04 (or larger?) possibly just set it to spray at 10psi or something... and set mbc limit to 15 - 17psi?

 

that :should: be good for mid 200's chp right?

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OK, so last night I headed back home to the shop to get crackin on the install...

 

We got the injector (80's Saab) mounted, fuel run to it. The saab injector uses a banjo fitting on the top, but we had pieces laying around and it worked out fine. Tested the funtionality by just putting 12V to it, worked fine.

 

I got the pressure switch plumbed, and got that tuned to trip at 9psi.

 

I didnt get around to wiring the switch up to the injector yet becuase the car then ran out of gas and we didnt have any race fuel and becuase 6pm came and i went to a car show with my bro and his '70 Nova (he got a trophy).

 

so, the injector is in and working, the switch is in and working. just gotta wire the two together (no prob at all) and get it tuned right, then hit the track.

 

 

 

-matt

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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

 

I made a cool air induction on my 87 gl10.

 

I took the maf adapter and put a peice of flex hose on it. Than I drilled a 3" hole through my inner fender and mounted a big K@N filter in between my fenders where the stock resonator went. Ill get pics soon. I had a few, but I acidentally deleted them. So now my open element filter is in between my inner and outer fender with the plastic mud gaurd sheilding it from the elements. It works great.

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This band-aid works VERY well and by the looks of the inside of the 200k engine I used it on last year, it seems to keep things in check too. This lets the car run normally on the stock injectors for daily driving then adds a little extra juice when the foot gets heavy.

Of course I do my own fabbing of parts and I get most everything from the JY, I have less than $500 into my whole car, including the car! Show me a stand alone system that can beat/ or match that.

 

The Saab injector is a little bit bigger (flow) than the ones from the VW engines, and 9 psi is way early to trigger it. My testing showed that 15psi is where the stock fuel system starts getting overworked. I have my injector come on at 12 PSI because the needle on the boost gauge swings really quick and I think it to be safe to have a little head start on it.

 

My RX did have two pressure switches on the passenger wheel well, I hear from most people that the fuel cut-off switch went away in 87, I juess I have an early 87 or something, weird.

 

I have a video of that 14.3 run and it's about 5.5M in size if anyone is interested in seeing it. My ignition cut out towards the end of the track after my intercooler water supply got hot. I don't know how to post a video on the net yet. Give me your address and and I'll send it to ya.

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.

 

The Saab injector is a little bit bigger (flow) than the ones from the VW engines, and 9 psi is way early to trigger it. My testing showed that 15psi is where the stock fuel system starts getting overworked. I have my injector come on at 12 PSI because the needle on the boost gauge swings really quick and I think it to be safe to have a little head start on it.

 

I have a video of that 14.3 run and it's about 5.5M in size if anyone is interested in seeing it. My ignition cut out towards the end of the track after my intercooler water supply got hot. I don't know how to post a video on the net yet. Give me your address and and I'll send it to ya.

 

I probably would have found that 9psi is too early through testing, but knowing now will save some time, thanks. I wouldnt mind seeing the video, Im going to make some when i get over there. I'll PM you my email.

 

I think I might have surpassed the $200 mark with the XT (car included), the only things purchased were: Battery, Tranny cooler, K&N panel filter, gauges, pressure switch, some random fittings, $5/gallon fuel. Everything else was gathered up around the shop.

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Chuck (aka boosted) I was just looking back on the first post here... you ran 14.3 @90 , just wondering if you felt the speed was off a bit than what it should be. I ran 14.9 @93 with mine, i just thought that you'd be in the 95-96 range with that time.

 

low 14s are rediculous, so obv theres nothing to complain about

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You know, I still have a hard time believing that the stock turbo is anywhere near efficient at 15 psi.... anyone have a map for the VF7? how do you guys know the turbo isn't just blowing hot air? :lol:

 

Matty, could you post pics of how you connected fuel to the injector?

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I get most everything from the JY, I have less than $500 into my whole car, including the car! Show me a stand alone system that can beat/ or match that.

 

 

ok then see you at athe show and i will show you :)

oh and i got my turbo to intercoole line problem solved.. using parts off my turbo dodge minivan coupled to parts off a maserati bi turbo lol

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I have a compressor map of the stock turbo somewhere, I'll see if I can find it. Yes, the 15psi on the 1.8L is getting a little out of the prime efficiency range and I'm sure it's blowing a lot of hot air. My T3 setup last year wasn't really that much more 'grunt' than the stocker. I'll be using a dual thermocouple with data logging for my new water-to-air intercooler setup with boost gauge on the entry and exit to calculate intercooler efficiency. This should give great baseline data for a stock engine running high boost on stock turbo.

 

My mph in the 1/4 is probably due to the loss of power at the end of the track. I have a heat exchanger that I'll be using in the front of the car to cool the intercooler water before it returns to the tank,like a Syclone/Typhoon. The setup is just pump-cooler-tank right now. Hey, I got it all thrown together right before the race. I had no idea that a gallon of icewater would get so warm in just a few seconds.

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hey for information

the intake air temp on my megasquirt shows me at 220F degree's when i had no intercooler @ 10 psi

 

 

wonder how much my intercoler will drop the temp

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