montermahan Posted July 25, 2015 Share Posted July 25, 2015 I have a trike i built using an EA82 engine and VW automatic. Figureing my gear ratio, I should be running 130 MPH at 6,500 RPM. I run out of power at 90, which is 4,500 RPM (fast enough I know). I cruse at 60 and it is 3,000 RPM. was wondering what a stock one runs at. Quote Link to comment Share on other sites More sharing options...
jono Posted July 25, 2015 Share Posted July 25, 2015 stock would be a choice of diff ratios 3.7 or 3.9:1 and whether was the 3 speed auto, 4 speed auto or maybe even the choice of manuals PT 4WD or AWD may have had differnt top gear ratio ? Reckon 3000 is about what most of mine have done at 60 mph so your engine is probably close matched to what runs in the Subes. They seem to be most fuel efficient around the torque peak of about 2600, 2700 ? Quote Link to comment Share on other sites More sharing options...
Sapper 157 Posted July 25, 2015 Share Posted July 25, 2015 stock would be a choice of diff ratios 3.7 or 3.9:1 and whether was the 3 speed auto, 4 speed auto or maybe even the choice of manuals PT 4WD or AWD may have had differnt top gear ratio ? Reckon 3000 is about what most of mine have done at 60 mph so your engine is probably close matched to what runs in the Subes. They seem to be most fuel efficient around the torque peak of about 2600, 2700 ? +1 When I run my wagon at about 2600 (55MPH) I can get about 30-34mpg When im running at about 3000 (60-62mph), I typically get around 26-28mpg Of coarse mine is an EA81, so I guess there are a few differences that could factor in. Quote Link to comment Share on other sites More sharing options...
DaveT Posted July 26, 2015 Share Posted July 26, 2015 My SPFI EA82 powered wagons with 3AT transmissions turn about 4000RPM at 65MPH. A little higher going uphill, a little lower down. They handle typical hills on the highways around here ok. I have one 3AT from an 86 which was carbed. It has slightly different ratios, and bogs down on hills noticeably, even with a SPFI engine. Quote Link to comment Share on other sites More sharing options...
tweety Posted July 26, 2015 Share Posted July 26, 2015 The VW full automatic came out in the type 3 and type 4. There is a difference in that the type 4 diff housing had mounts high up on each side of the differential housing in addition to other mounts. I found that out the hard way. Thought I had a type 3 transaxle and went to install a spare one and - no upper mounts. Both these auto transmissions are the same however - the type 3 auto trans. The type 3 transaxle has (to my knowledge) a 3.67:1 differential ratio. The type 4 has 3.9:1 ratio. Not much difference in my opinion. My trike has 15 inch rear wheels. They have 295/50R15 tires. The revs at 60mph (102kph) is like yours Montermahan is around 3100-3200. There was no 4 speed ever made and no possibility to lower the rev except by either one of 3 means. 1/ Take your diff to an expert to get them to change the gearing. An expensive exercise. If you did this and ended up with say 2600rpm @60mph then you'd need to boost engine output or it will die approaching a hill and you'd be revving it high in 2nd gear. Your engine the ea82 like my ea81 isn't easy to do this with. 2/ Change the rear tires to a larger circumference/diameter. You can (if you have 15" wheels") go to a 275/60R15 tire. This will lower your revs at 60mph about 5% 160rpm. It will also give you slightly higher mph in the other two gears. Being a light vehicle your engine will enjoy this and not die on hills. You could also seek wheels like 18" diameter and larger tires than the 275 tire to get even lower revs. So I'd factor this in to get your rev down to say 2900 rpm. Use a tire calculator. Google tire calculator. You'll be looking for 10% more in circumference. eg say you had 295/50R15 tires and changed to 265/70R15 tires. You'd get 11% larger in circumference and drop your revs down that much. You might need to toy with this concept as its the easiest way to get to your objective. Tire sizes might not be available too that you want. eg 275/50R18 (if you change your wheels) will drop revs @ 60mph by 8% also ideal. This also means that your 1st gear on your auto that runs out of breath at 25mph will run out of breath now at 28mph and 2nd from say 62mph will go to 67mph and so on. This sort of playing around with larger tire and wheel sizes would not be as ideal for VW cars and vans of their day due to the heavier weights. 3/ Change transmissions to a manual and seek highway gearing common in trikes. 4/ Cruise at a slower speed. The VW 3 speed auto is a good cruising transmission without the complexity of the overdrive transmissions. They are robust able to take small V8 or V6 engine torques. They will last providing you change the seal between the trans and the diff every 7 years or 60,000 miles. Or if it fails your trans will die!!. So pull it out and put a gasket/seal kit in it. I've learned to live with it. I now use ear plugs if on a long drive. Placing more mufflers on the ea series engines as we know will only make you lose power. But your muffler system should have a crossover exhaust pipe to each exhaust side. Hope that helps. Larger wheel and tire combination is the easiest answer. Quote Link to comment Share on other sites More sharing options...
subnz Posted July 26, 2015 Share Posted July 26, 2015 My old 86 / 88 Ea82 5MT D/R GL wagons: about 3000rpm @ 60mph ( 3.9 diffs on 13 x 195 x 70 tyres ) Quote Link to comment Share on other sites More sharing options...
montermahan Posted July 26, 2015 Author Share Posted July 26, 2015 Thanks for the good write up tweety. I was curious what a stock Subaru was turning at highway speed's. The VW engine Redlined around 5,000 and at 3,000 RPM it was around 60 MPH, and the Subaru redline around 6,500 and I am turning 3,000 at 60. DaveT stated his was turning around 4,000 at 65. Mine at 4,000 would be 80. I would like to go with smaller tires to get my RPM up to 4,000 at 65, would have more power all way round, but I also like the 3,000 at cruse. Would be curious to know the difference in gas mileage and engine longevity. Maybee when It cools down around here, I will stick on a set of smaller tires and test for myself. I am now running 205/70R15's. I put a push button on my handlebars for the electric shiftdown, so I can hit it to pass or hold it in when going thru the gears for a higher shiftpoint, which is still 5,000 RPM, I don't think I want to change the governor weight's to get it up to around 6,500. sound's like it is really screaming at 5,000, but I'm used to VW's. Quote Link to comment Share on other sites More sharing options...
tweety Posted July 27, 2015 Share Posted July 27, 2015 the VW type 3 transmission has a vacuum governor at the bottom passenger side rear where the vac hose goes into. Simply take the vac hose off and you can see a really small spade screw inside the governor. If you want the trans to shift at higher speed unscrew if you want it to select the gears at lower speed...screw it in. Do it half a turn at a time. Tony Quote Link to comment Share on other sites More sharing options...
l75eya Posted July 27, 2015 Share Posted July 27, 2015 4,000 rpm with the 3at transmission gives you 67mph. These motors can run that 4k all day and if they are all maintained, you wouldn't need to worry about that impacting the lifespan at all. Short stroke ftw. Quote Link to comment Share on other sites More sharing options...
turbosubarubrat Posted July 27, 2015 Share Posted July 27, 2015 My ej22 swapped hatch lifted 6" with 235/75/r15 tires runs about 2500-3000 in 4th gear at 60-65. Haven't shifted into 5th yet since i don't need to go faster than 55 until i go on the highway which would be 65-70. I put in the 3.9 5 speed d/r trans and it's a good combo. Quote Link to comment Share on other sites More sharing options...
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