3k Or 4k??

[springersrolla]

hey guys this is my story. Picked up a ke35 coupe off an old couple 2 owners done 114000km stock as a rock, rear venetians, awesome interior and exterior, motors alright, if anythin it probably hasn't ever been revved past 2000rpm. its valve stem seals are shot so blows a little oil, compression is good at 140 each cylinder.

 

Now my story is that my misses wants to keep it standard, but i wanna put an sr20det in it, so instead of the sr, I'm thinking of freshing up the motor so it's reliable and quick. The 3k's got good compression and i was thinking of getting the head reco'd next week so it stops blowing smoke, but then i'll be tempted to get a cam, and then exhaust, then carby. I'm planing on another muffler cause its f@$ked, its running 1.5" pipe so that should be big enough for a 3k right? the carbys leaking at the plunger pump and the inlet/exhaust manifold gives me the shits cause its joined by that triangle shit.

Has anybody done the swap of a stock 3k to a stock 4k and was it worth it?

 

Whats the 4k like in comparsion to the 3k is 100cc that much of a jump in power, with the compression that i've got should i keep the 3k in there cause its all standard and shit, or should i step it up to the 4k? the motors sitting on between 4000-4200rpm at round 105km in the 3k, will the 4k rev lower?

 

Whos got the information bout these motors that wants to have a chat that i can ask some questions i love working on old cars cause there simple and usually cheap when u can find parts I'm in brisbane so if anyone can give us a help would be good, cheers

[toyota_ae71]

Hey mate,

yeah i would go a 4k or possibly 5k as they are still a straight swap, ive got a 4k in my rally car thats done 280,xxx km's and still has 155psi in all 4 cylinders with extractors through to a 2" exhaust, and i had a 32/36 weber on it. And it keeps up with skylines at my local car club and has no trouble sliding on dry bitumen. with the help of a locker of course. So if its just your daily keep a warm k series engine in it as they still do go very hard. But if you have the money ($5,000-$10,000)for the sr20de+t go for it.

i have a video of my 4k on bitumen but its VERY shit quality but ill chuck it up anyway.

[son of stig]

I'm going through this head scratcher as well. got a complete 3k and 4k setup that I'm swapping bits between.

 

i actually read somewhere that the stock 4KC, with californian emissions, is about 58HP. the stock 3K is just over 70HP!

 

i believe it too, the 3K from an old KE30 sedan i had has always gone better than the 4KC from a ke55 coupe. revved more freely, throttle more responsive, and pulled harder. the 3k has bigger ports all round too, but I'm not sure if that means its the bigport motor or if all 3ks are like that?

 

that said, ive ended up putting the 4k in the car as it was in better condition, now i can't decide whether to work the 4k or rebuild and work the 3k.

 

from memory i reckon the stock 4k with a 4 speed in the ke55 sat on about or just below 4000rpm at 100kph.

Edited January 12, 2009 by son of stig

[philbey]

The 58 HP was probably based on SAE horsepower, a theoretical calculation on a using engine parameters to determine HP

 

Was used in the late 70s in the states when cars were taxed based on horsepower as it usually came up with lower figures.

 

I doubt the 3K has more grunt than a 4k, anecdotally most people seem to find them gruntier.

[Hiro Protagonist]

The 58 HP was probably based on SAE horsepower, a theoretical calculation on a using engine parameters to determine HP

 

Was used in the late 70s in the states when cars were taxed based on horsepower as it usually came up with lower figures.

 

I doubt the 3K has more grunt than a 4k, anecdotally most people seem to find them gruntier.

 

And a lot of 3K max figures you see running around will be for a 3K-B (as those were the biggest numbers), which has the unfair advantage of twin carbies.

[son of stig]

can't seem to find the nice neat table of power figures i found the other day, but this is off some other website about corolla history

 

"Early Corollas in this range (KE3x) with 3K engines produced 73hp (54kW) from just 1166cc. However emissions became a problem further into the 1970s, and the 4K engine in the KE5x series produced only 60hp (45kW), despite and increased capacity of 1290cc. These figures are fairly optimistic (probably tested without ancillaries such as alternators or water pumps) to make the car look good for sales, in reality most Corollas of the time produced about 30hp (22kW) at the wheels, which can be estimated to 45hp (34kW) at the flywheel."

 

read more here

[coln72]

Never liked the 4k much - personal opinion. Took a bit of work to get it to rev. Would rather a 3k but would take a 5k any day :y:

[springersrolla]

i like the way the 3k feels ive been driving it abit lately, probably just get the head done with a little port, sort out the carby, and do cam and lifters with the head off, should drive nicely. wont cost much to get that sorted and i can always build a 4k up with the car running the 3k.

 

next question would be what carby to use with a tighe cam, exhaust, regraphed dizzy?

[KEI069]

Id be keeping the 3k, their a good little motor that revs nice. With the cam your planning i reckon

a weber 32/36 carb woulb probably be the go and a set of decent extractors, 4 into 1.

As for the revs at 100k's the engine capacity wont change that, but your diff gears will if your worried about it.

Good luck with it all.

[D1doony]

3k head 4k bottom end = lower compression + turbo = win

Edited January 14, 2009 by D1doony

[Jason KE30]

good idea going with the 3k

i find that it goes harder then any other 4k i've tried out

could be cause it hasn't been thrashed at all in its life (until now) :|

[springersrolla]

you don't think a 32/36 would be too big??, having said that I'm contemplating twin dellortos/solexs if i could get my hands on some. anyone got suggestions on a carby or do u reckon to have real small jets? darn it'd be good up top end with that carby