4sp trans into a 5sp car...
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4sp trans into a 5sp car...
Like the title says, I'm plannying on putting a 4sp. in my si to help boost the fuel economy and I dont think 5+mpg is out of the question by doing so. I've done a million d series swaps but all have had 5sp and I was wondering if I use the 4sp. if the linkages from my 5sp. are all compatible and will work normal with the 4sp. trans. or if they will be any issue using it in my si...Leland
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Re: 4sp trans into a 5sp car...
Strictly speaking from a mechanical sense the only problem you would have would depend on what year the two transmission are coming from.
1988 - 20 Spline, 180mm flywheel (from memory don't completely quote me on sizes)
1989 - 21 Spline, 190mm flywheel
1990-2000 - 21 spline, 210mm flywheel
Something like that, anyways so if you have matching year transmissions if not you might have to change up you're clutch and flywheel combination.
1988 - 20 Spline, 180mm flywheel (from memory don't completely quote me on sizes)
1989 - 21 Spline, 190mm flywheel
1990-2000 - 21 spline, 210mm flywheel
Something like that, anyways so if you have matching year transmissions if not you might have to change up you're clutch and flywheel combination.
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Re: 4sp trans into a 5sp car...
Yea im not worried about the clutch or flywheel issue in the 88, i'm hoping the trans isn't an 88 tho.lol, if it is I have a clutch and **** lined up already. So you think it'll drive like a normal 4sp. would in my 5sp. car? I thought so but wanted to make sure b4 I bout it.lol
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Re: 4sp trans into a 5sp car...
so what do you think if i'm driving it like a normal person. I have a 500hp del sol and i'm not interested in racing my dd ef,lol. So i'm thinking it should get close to 50mpg. I know my buddy had an ef hatch w a 4sp. and it got 50mpg all day long.lol
#6
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Re: 4sp trans into a 5sp car...
i got about 35mpg in my bone stock STD with 4spd and 70hp d15b1. i think with mods i could have gotten a lot better. also i went with a dx 5spd eventually and it was a lot better for highway driving.
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Re: 4sp trans into a 5sp car...
well my car has the si motor so its like 92hp I believe so I figured w that and the standard bolt on's it'll do pretty good. I guess we'll see.lol. Its gonna be weird driving a 4sp tho.lol
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Re: 4sp trans into a 5sp car...
Seems like a waste of potentially fun si. Why not trade it for an HF? I am sure there is a bunch of people who would have wanted a trade like that.
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Re: 4sp trans into a 5sp car...
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Re: 4sp trans into a 5sp car...
I dont "need" anything. This is a thread about a 4sp into a 5sp. car and not what you think I should do otherwise. I already have the 4sp and its not hard swapping it in there and wtf would I wanna tear anything apart like that? I know I could do it but it totally un-necessary. So if your not commenting on the 4sp swap then just move to another thread. Thank you.
#16
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Re: 4sp trans into a 5sp car...
no you wouldn't, the inner hub on the axle is all the same, just the outter ends are different. OP, it would be like any other trans, although you'd be ending up with a really sucky, no acceleration 4spd tranny. if that's what you want then go for it. i personally don't like it, because it makes pulling out in traffic a bitch cuz the car doesn't take off like it would with a five speed (i have a std civic) but again it's up to you. pull out the si tranny, if you get a 4spd from an 89-91 you can just re use your clutch fly wheel etc. if its from an 88 you have to use the 21 spline stuff.
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Re: 4sp trans into a 5sp car...
cool its a 90 and i'll see what hpns with it. I'm not worried bout the lack of power bc its going into a motor with 20+ more hp so we'll see w hpns. I'll do a write up on it for future reference.
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