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question about bigger tires


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i was climbing up a fairly steep hill in 1st gear low range in my 82 ea81 and it started bogging pretty hard so i had to stop a couple times up the hill to give it lots of gas and pop the clutch:rolleyes:

 

so to my question: i know lots of people put bigger tires on these cars and i was wondering how they do with bogging down, if i put a weber on would that eliminate the problem? or am i pretty much just looking at an ej swap?

 

please help!!

 

thanks,

ryan

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If your thinkin' about going to larger tires, & your asking if it will affect your gearing, the answer is yes. I'm runnin' a Dual Range w/ 3.90s of coarse, & switched the rear over to a 3.90 Limited slip. I've done the five lug deal on my 88 GL10 T, & at first I ran the 205 60 14s that were stock on the XT donor car. At that time, switching from 13 to 14s, it felt like I lost a full gear. Just recently, I switched to 02 O.B. whls. w/ 205 50 16 Kuhmo Ecsta ASTs, I think it dropped another gear. I'm sure there's formulas using o/s dia. etc.,to chart the actual ratios, but if your usin' it for off road, it gonna' hurt. I've gathered a 4.11 tranny & r. diff., but that's gonna involve some hi. $$$ machining & other work. If I'm gonna go to that much effort I'd rather switch to 4.44s., & have more crawl-ability. Don't know about your carb question, a little hp. gain I'm sure, but if the engine's in good tune now, I doubt you'll see a big improvement in the bog factor. Luck with your project, S.

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i was climbing up a fairly steep hill in 1st gear low range in my 82 ea81 and it started bogging pretty hard so i had to stop a couple times up the hill to give it lots of gas and pop the clutch:rolleyes:

 

so to my question: i know lots of people put bigger tires on these cars and i was wondering how they do with bogging down, if i put a weber on would that eliminate the problem? or am i pretty much just looking at an ej swap?

 

please help!!

 

thanks,

ryan

 

That must have been one steep hill! In my old 86' hatch with ea81 and D/R I could climb up a tree if I could have gotten the traction!:grin::grin: Maybe you need a tune up?? :confused: I ended up putting 29 swampers on that car and it still did fairly well on some steep stuff. Obviously not as much torque but still did pretty well for 55HP:banana: Theres a simple answer to your problem however. EJ22.

 

-cody

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That must have been one steep hill! In my old 86' hatch with ea81 and D/R I could climb up a tree if I could have gotten the traction!:grin::grin: Maybe you need a tune up?? :confused: I ended up putting 29 swampers on that car and it still did fairly well on some steep stuff. Obviously not as much torque but still did pretty well for 55HP:banana: Theres a simple answer to your problem however. EJ22.

 

-cody

 

it was a very steep hill!! lol. that car climbs like a billy goat!! god i wish i had the money for an ej swap! im prolly gonna end up going with some swampers also. but i guess ill just have to figure it out through my own experiences. lol

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If you don't have a dual range 4x4, that's your first problem. Swap the tranny out for a dual range 5spd if you can.

 

Weber, or better SPFI swap on the EA81 will help a lot. That's a good stage to be at for a while until you can afford a EJ swap.

 

My loyale would bog out on steep slopes in the woods sometimes with the D/R tranny in low but with 235/75r15 a/t's on. Ditching the EA82 for an EJ22 fixed that, but then I was replacing axles, clutches and trannys all the time.

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Now you can do some things to your ea81 to help it out like putting a weber on it and upgading to a ea82 carb intake to gain some hp&tq or spfi if your good at wiring which gives you around 90hp in stock form (with a soild lifter small valve ea 81) with better gas mileage and it your feelin froggy pull the heads and port the crap out of them and do a valve job you can go up a little with valve size and deck the heads .020 or .030 doing all this and not spilting the case you might get around 105hp max but its alot cheaper than an ej swap and the car is down for less time and this is without changing the cam or pistons and petty much rebuilting the motor

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Now you can do some things to your ea81 to help it out like putting a weber on it and upgading to a ea82 carb intake to gain some hp&tq or spfi if your good at wiring which gives you around 90hp in stock form (with a soild lifter small valve ea 81) with better gas mileage and it your feelin froggy pull the heads and port the crap out of them and do a valve job you can go up a little with valve size and deck the heads .020 or .030 doing all this and not spilting the case you might get around 105hp max but its alot cheaper than an ej swap and the car is down for less time and this is without changing the cam or pistons and petty much rebuilting the motor

 

Not sure of your source on the HP numbers but they are flawed. Installing a Weber might but unproven numbers. It will respond better. You will not gain 19HP by swapping in SPFI. You will get a better delivery system that is more efficient. Hence the gain in fuel mileage.

 

Also, you can not deck your heads .030 without modifying your intake mounting holes. Then, you run the risk of the water ports not matching up properly which will cause overheating.

 

Please keep your information accurate and maybe cite some sources when doing so if you have not dyno'd the vehicle to prove your numbers.

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I did get my brat dynoed 3 times in the past 5 years once bone stock 5years ago as a base line it had 67hp at the front wheels then when it had 29k on it which is about 73-75 at the flywheel then I had it dyno again after a spfi swap with the heads shaved and ported the intake did have too have the holes opened up a bit and it was ported out the injector was change out for one that flows better the throttle body was bored out and a new throttle flip was made. at that time it made 86 hp at the front wheels.which is about 91-95 at the flywheel. its now on round three which is a delta torque cam with my verison of the spfi pistons I made at work the heads chambers welded up 1.98 & 1.94 valves I finish this a year ago and redyno it now it has 101 hp at the front wheels which is about 109-113 at the flywheel

 

and if you want them I still have the dyno print outs I would just have to scan them to post them But I see no need Its not a hot rod is a brat so thats where I got my numbers but every engine runs different some are weaker and some are stronger in stock form and you may have to run smog stuff which kills some power on my brat there is no smog stuff left (no egr or cats) and I have 2in duel exhaust

Edited by 84gl
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I did get my brat dynoed 3 times in the past 5 years once bone stock 5years ago as a base line it had 67hp at the front wheels then when it had 29k on it which is about 73-75 at the flywheel then I had it dyno again after a spfi swap with the heads shaved and ported the intake did have too have the holes opened up a bit and it was ported out the injector was change out for one that flows better the throttle body was bored out and a new throttle flip was made. at that time it made 86 hp at the front wheels.which is about 91-95 at the flywheel. its now on round three which is a delta torque cam with my verison of the spfi pistons I made at work the heads chambers welded up 1.98 & 1.94 valves I finish this a year ago and redyno it now it has 101 hp at the front wheels which is about 109-113 at the flywheel

 

and if you want them I still have the dyno print outs I would just have to scan them to post them But I see no need Its not a hot rod is a brat so thats where I got my numbers but every engine runs different some are weaker and some are stronger in stock form and you may have to run smog stuff which kills some power on my brat there is no smog stuff left (no egr or cats) and I have 2in duel exhaust

 

I appreciate you following up. I stand corrected. What correction did you use? What dyno did you use? I agree that every engine build is different. I see you did a bit more work than just swapping in SPFI though. The extra air flow definitely made a difference.

 

Ken

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It was dynoed at ride revalution in Johnson City TN on their free dyno days as for what brand dyno I don't reminber but it was the hydro type Its been almost two years. now on the intake I port matched the intake and coolant ports with a die grinder and trial and error with a fiber optic camera at work the valves were also trial and error now the pistons were a have to case Because every ea82 I torn down at the junkyards had something wrong with them broke lands, creaks so I took two to work and made a set on the mazka quick turn 50 and vc160 mill I made them out of 6060 alum. to stock specs.

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bolts right on the only things to worry about are you may have to grind down a high spot in the middle of your block and bend a metal line that goes to the heater core and depending on your alt bracket it may have to be ground as well

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