SPFI - How fast?

[Guest grease weasel]

I made it to 112mph slite down hill start to long straigh away. But there was so much air going under the car it started to float around.dicey to go 130 I'd think with out some front fairing or lower the car.

[Guest subarustyles]

I got mine to 105mph going through WA last year...I got so scared:eek: cause I had crappy tires...I should try to peg it out again cause I have good low-pro tires and my car is lowered alot more than stock.

[Guest oobnuker]

Subarustyles: You got any pictures of this badboy? Sounds like a cool ride.

 

Everybody else - keep 'em coming. I love it. The air has been cooler in CT at night so my car is still screaming along nicely when I get a chance to get out there and tear up the highway :rollin: .

[Guest calebz]

Got my 87 turbowagon up around 100 going through wyoming a couple af months ago.. was still in 4th.. wasn't even at redline yet.. and that was with a vacuum leak! haven't tried to top it out yet

[Guest oobnuker]

Well by all means - tach it out! Safely and all that yadda yadda...

 

I think I've hit 95 in 4th in my SPFI...Not sure if I was at redline though. Can't seem to redline in 5th...must be an aerodynamic limitation...

[Guest WagonsOnly]

My father made it to 53MPH (maybe a little faster, my speedo is about 10% off) going downhill, with a tailwind, on the way back from the last Moosens meet in his red wagon. (The "clutchless manual" '88 DL SPFI he had.)

 

The first DL he had topped out around 90-95 on the freeway with an automatic and A/C. I don't know about the other one he had, as it never had decent tires on it and most of his commuting at that time was around town.

[Guest wjmgl10]

back in the days...aobut 2 years ago when my GL-10 was BONE STOCK...I hit 116 MPH. I never have tried a top speed test now...its supposed to get up to 140 at 6500 in 5th tho.

 

I bet that XT I have my eye on will do that...

 

The RX...75 so far...on some little paved residential road.

 

I had a 1996 Outback up to 110. All stock.

[Guest Shemaryahu]

I had my old 93 Legacy L (EJ22) up to 135 once. I'm curious to see what I can do when I drive my new XT home from RI.

[bgd73]

Upon same question-- I found this 3 year old thread

My blurry pic is 100mph even @4800 rpm in a 2wd 5spd on tall tires and fresh rims. Going uphill downhill and corners on highway I didn't know were sharp.. I chose to keep it there at 100 even, at 1/4 throttle for 10 miles (it seriously could have cruised to 120mph on the 3.7 final gear).I really wanted to know how casually fast after stiffening the rubber intake boot (it was very responsive to my fix). I absolutely knew they were way underestimated.I wonder what would a turbo high comp mpfi do to get to top end.. this 2wd would do the same but take longer to get there. I swear I could have done this speed for 100 miles (do not try at home kids- I'm a lunatic sometimes on my many many repairs and hacks and confidence)

[WheaT_BeeR_MaN]

i worked for southern oregon subaru when i was 18. i did some dealer trades getting a few outbacks up to 130 going to bend. of course i got the wrx up to that in town! it took it a while to get to it. my 83 i got to 95 np.

 

[jeffast]

okay my speedometer does not work but in my 89 xt-6 5spd i got it to 5500 in fifth all i know was i was hauling rump roast and as soon as i noticed i slowed down i was just curiouse how fast that is with the 3.9 final drive ratio on stock tires

[bgd73]

Upon same question-- I found this 3 year old thread

My blurry pic is 100mph even @4800 rpm in a 2wd 5spd on tall tires and fresh rims. Going uphill downhill and corners on highway I didn't know were sharp.. I chose to keep it there at 100 even, at 1/4 throttle for 10 miles (it seriously could have cruised to 120mph on the 3.7 final gear).

 

 

Hey speedo synch question-- what is 4800rpm in 5th gear on 3.7 final gear? My speedo sticks, and hangs, I already got a speeding ticket because of it. Another note about the ea82 sucking thru a 30mm spfi straw- that is less than 1.25 inches (1.18).It started cooling down around 90mph (on my bad speedo) as I was accelerating to gain noticable throttle, and climbing faster to who-knows-what for top end. Incredible- it was actually cooling to nature even tho the demand was greater to perform.I have never encountered an engine that did this under high demand for any length of time- especially to note 158000 miles on just about all original engine parts. Where is that new EA82 getting manufactured again anyway

[bgd73]

Upon same question-- I found this 3 year old thread

My blurry pic is 100mph even @4800 rpm in a 2wd 5spd on tall tires and fresh rims. Going uphill downhill and corners on highway I didn't know were sharp.. I chose to keep it there at 100 even, at 1/4 throttle for 10 miles (it seriously could have cruised to 120mph on the 3.7 final gear).I really wanted to know how casually fast after stiffening the rubber intake boot (it was very responsive to my fix). I absolutely knew they were way underestimated.I wonder what would a turbo high comp mpfi do to get to top end.. this 2wd would do the same but take longer to get there. I swear I could have done this speed for 100 miles (do not try at home kids- I'm a lunatic sometimes on my many many repairs and hacks and confidence)

 

I found an interesting site that can proportionately align a bad speedo with incredibly smart math (realistic answer):

the above photo at 100 mph and tach accurately at 4800 == 112mph on my soob. Upon getting close to the 5200 max hp (I refuse to go there due to my little tires speed rating) even tho very easy to get to, would equal 121 mph.

check the site out and avoid law troubles:

http://www.4lo.com/calc/gearratio.htm

if you have no transfer, neutral it with a "1".

Good Stuff.

The tire calculator site only shows speedo differences at 60 mph or 55mph, this site gets it dynamically. Use both to figure tire diamter, as it is a variable

http://www.miata.net/garage/tirecalc.html

 

Also, I wanted to compare a 195/60/15 in theory. The only real gain in a bigger tire is a safe speed rating that can handle it. This tire put into equation with the ea82 at 5200 pm and a 3.9 diff is only 123.1 mph. It is to say, a 13 inch tire can indeed go there with the right diameter, but unsafely.

Another theory was the fastest oem subaru (spfi loyale generation, or any ea82 for that matter) with its tallest differential (3.4) on the aforementioned 15 inch tire in 5th gear at 5200 rpm == 140.7mph, of course rpms higher than that with the tall ratio OEM could no doubt hit 150+ before 6000rpm.

 

have I really answered this age old question?!

[Davalos]

'90 Loyale Wagon 2WD no mods, pansy tires.

 

I'm embarrassed to say I haven't taken mine over 70, because the motor sounds like it's going to tear itself thru the firewall and push me into the Next World.

 

When I want to go fast, I hop on my Vmax. Stage-7 carbs, Cobra 4:4 exhaust, Vboost, 168 hp on the dyno, and 0-60 in 2.3 seconds. I have burried it many times, with plenty more room on the throttle, but I ran out of room in the Balls Department.

 

[bgd73]

Not to keep babbling, but there is a serious answer I needed,to this threads initial question.It is also for anyone who has changed the tires to bigger then the 23.* inch oem diamater. For Example: I was passing everone on the highway for the 18 months I have had my car and every highway trip. I have just learned today, that my 3500 rpm in 5th gear, I have been doing 81mph. That is a hefty ticket where I live, all on account of a speedo claiming 70. Now I know 3000 is not the 55 I thought I was crawling at.

 

I have no clue why there is a large pic of a vmax in this thread.. I am fairly certain it is off topic.

[joostvdw]

 

I have no clue why there is a large pic of a vmax in this thread.. I am fairly certain it is off topic.

 

I believe your question is equally off topic

 

but, to answer your question, find out your original tire sizes, using the tacho and final drive ratio's calculate the speed your suppose to be going with original tires, than do the same with your bigger tires, that way, you'll know the difference and can anticipate for it. and most importantly, avoid hefty fines :-p

[nvexplorer]

Going from Reno to Winnemucca I average around 80 mph with a record speed of 96 MPH (gps) The speedometer stayed at 90 even when the gps said 80 after that and eventually came back down to the correct speed. Oh and I got 30 mpg that trip too!

[bgd73]

I believe your question is equally off topic

 

but, to answer your question, find out your original tire sizes, using the tacho and final drive ratio's calculate the speed your suppose to be going with original tires, than do the same with your bigger tires, that way, you'll know the difference and can anticipate for it. and most importantly, avoid hefty fines :-p

 

Thanks for repeating my posts purpose and answer. I'll forget what I posted and go back and do it again with your advice and answer the answer I already accomplished (scroll up a few threads):cool: . I have inquired of this before.. the actual question of how fast is difficult on my car. That site I mentioned helped.

It hit the nail right on the head. The .783 5th gear is very tall for a little engine.. could take a long time if the ea82 hit 9000 rpm on a 3.4 diff. Holy Cow. I am wondering if the car has the wrong speedo gear for alignment. As there is not much sticking anymore, it seems to be perfectly off by 12mph. I wondered if this car had 4wd original, the bolt holes are open and clean for rear end, like something had filled them. Also a wear on thje unibody, I have only seen happen on the 4wd. Anyways, it may be a clue to a perfectly wrong speedo. (the diff gear changed to the 2wds- misaligning accuracy)

A lighter car is a faster one.. very complex thing to figure.

Has anyone done a closed track or fly across the salt bed. I bet this driveline would do 150....taking awhile to get there in a lighter chassis.

It is not all that big a number when you have done it (not me in a soob).If the old soob is slow, it is being made to run as such.

[Davalos]

I once got OUT of a speeding ticket by telling the judge that my speedomerter was off because i had on larger diameter tires on my Maverick. I did some math for him & we discovered that it was like a 9mph difference between what I THOUGHT I was going, and what he pulled me over for ... so the judge bumped the ticket down a notch & asked me if I was planning on going to Law School.

 

I said "Your Honor, I applied to Law School ... but then they found out my parents were married." He gave me a confused look for a second, then said it was time for me to leave.

 

... would it less off-topic if I made the Vmax pic smaller? heh heh .... :cool:

[MoscowSubaruDude]

Bear in mind these are all via speedo's, which may or may not be accurate.

 

83 GL wagon, 2wd, 5spd-89mph on a back road in Moscow. Flat. Curvy.

86 GL hatch, 4wd, 4sp D/R-84 mph on the freeway. Flat.

83 GL wagon, 4wd, 4sp D/R-102, through my town. Running scared. Speedo didn't go hi enough, but my buddy in his little POS honda was doing 100 even, and I was passing him by just ever so little. Took 3 miles to get up to that speed.

87 GL-10 Wagon, Turbo, 4wd, 5sp MT-148, I-90 through Ritzville. Ticket for 100, radar said 148.

 

These little cars *can* go fast, if you really try. I was amazed at the turbo's speed... I was going dowhill, slight grade, and just decided to get on it, winding out every single gear to 7k. Couldn't see the tach when it hit top speed, because I was too busying making sure I stayed between the ditches. It was kinda cool to get the ticket, because, due to my faulty speedometer, which said I was only going 55 (stupid digi-dash), I never knew how fast I was going when I topped out.

[WoodsWagon]

97mph, calculated off spedo reading, and I believe it. I-91 coming down the conneticut river valley in vermont. 30" Mud King tires, SPFI howling. Cooked the exhaust gaskets right out, the manifold must have been glowing! Crossing expansion joints on bridges got sketchy, the car was drifting at that speed.

[Skatedownpdx]

got my spfi to 85 on flat:burnout: , didnt dare push it past that. if i wanted a fast car i would have gotten a newer soob

[daeron]

87 GL10 2wd 3at with stock sized tires and 130K on the odo did 102 on alligator alley.. loooong flat causeway built across the glades from ft lauderdale on the east coast of florida, to naples on the west coast of florida. flat as a board. the reading is off of a digidash, but ive never had any cause to doubt the speedo and i also got pulled for 78 in a 70 about ten miles later and he paced me.. and the speedo said 78 so it was accurate that high. IIRC, the tach was registering just under 5K.. i know i thought i had a few more i could go, but i also know i didnt want to go much higher. 102 was over a hundred, enough that i felt it had been achieved regardless of minor speedo inaccuracy.

[bgd73]

...

87 GL-10 Wagon, Turbo, 4wd, 5sp MT-148, I-90 through Ritzville. Ticket for 100, radar said 148.

 

These little cars *can* go fast, if you really try. I was amazed at the turbo's speed... I was going dowhill, slight grade, and just decided to get on it, winding out every single gear to 7k. Couldn't see the tach when it hit top speed, because I was too busying making sure I stayed between the ditches. It was kinda cool to get the ticket, because, due to my faulty speedometer, which said I was only going 55 (stupid digi-dash), I never knew how fast I was going when I topped out.

 

That year with turbo may have had the 3.4 diff, the tallest ever put behind an ea82. 148 could have been right on the money, accurately.

That is the driveline I am after... not so much for the turbo engine, but to put behind an n/a for everyday driving, very casually highway, lowering rpms on the tall diff final ratio.Taking abit longer to get to an outrageous top end, but to me the only place I creep up past the speed limits is on long straight a ways on long trips... having a calm engine would be even better.As it stands now, my cars speedo is acting like a 3.9 (very accurately off to be a 3.9 final), with a 3.7 result.The 3.454 info was found at cars101.com and the pdf file from this forum, only seen on the gl-10. It is a rarity. Seemingly like my 2wd 5spd is being found oem.I would love to put the 3.454 on a 2wd.. there would be no doubts to be the mathematically correct ingredients to be the fastest ea82 *ever*.

[daeron]

bgd- the NA engine may well not make enough power to top your theoretical driveline all the way out.... it IS only 84 HP maximum stock.. sure its got a peak torque of 110 or something, but thats at 2000 RPM. you would certainly attain a higher speed than i did easily.. but the engine WILL reach a point where it will refuse to gain speed, if you gear it steep enough.it takes power to make inertia, the more inertia you want the more power you need.. and youve got to run dry at some point.

 

not trying to deflate your aim or anything, by any means.. the steeper gearing you install, the higher your top end will be, no doubt... BUT you may top out your speed before youve topped out your RPMs. you get my point? you could put a 3.0 final drive box into the car, but you will NEVER make it to 200 mph with only 84/11 hp/torque...