4k/5k Bottom Ends?

[thomo]

hey, ive got a little '55 id like to keep up with traffic, was thinking mild head, cam, extractors, and super charger my question is, someone gave me a 5k but the bloody things missing a piston and rod, think they pulled it out to measure for turbo piston set up, is the difference between the 4k and 5k in the stroke or bore? can i use the 4k rods i have laying around? and how do i get rid of the hydrolic (?) lifters?

[Trent-KE30]

Heya Thomo, To get rid of the hydrolic lifters you use datsun 1200 pushrods and holden red motor lifters.

[TRD ke70]

yes you can use 4k rods but be careful there is a lite one and a heavy one.

match them up with the 5k rods, you'll soon see the difference.

 

the difference is in the bore size between a 4k and 5k, they use the same rod length and piston pin size.

 

as for the lifters, you can buy solid lifers for a 5k, they did come out with them, then just use the 4k rocker gear, but again there are diffences in the push rods, if you have a dished piston 5k, you'll need push rods from a dished piston 4k, if you have a flat top piston 5k (a little rare)

normal 4k push rods are the go.

 

check the FAQ for the part number for the lifters.

[coln72]

Why ditch the hydrolics - they don't limit revs that much. I see 8000rpm with mine.

[Boost+k]

Heya Thomo, To get rid of the hydrolic lifters you use datsun 1200 pushrods and holden red motor lifters.

 

have you tryed this? or just been told?

 

what excatly do you mean by "lifters"? the cam followers?

[Xany]

Yes it does work.....check sig. for my engine specs....

 

lifter: thing that sits on top of the cam....pushrod is placed on top or inside of the lifter....

[thomo]

thanks for the info fellas, all i have is a 5k block with 3 pistons in it and couldnt decide whether to bin it or rebuild, a local proformance shop (turns out hes an idiot) had nothing but bad news bout the whole idea

so as it stands I'm looking at 5k block, 4k crank and rods (if there the right ones) new flat top pistons, open chamber 4k head (not enough comp?) solid lifters, (cos i havent got the standard ones), 3 face valve job, HD valve springs, tighe 104 cam (same as 4k?) 4into1 headers 2in system, electronic ign, supercharger

feel free to laugh and point out any total accidents waiting to happen, or suggest any go faster ideas, keeping in mind my ex gets all my cash so this is so budget rebuild its not funny

lucky polishing is free!

[SLOTH Snr]

Do a bit of checking around there is a standard size

GM solid that fits the k heads. Read as many of the

5k threads as possible there is good info if you piece

it all together. I don't think you will have a motor to

be laughed at

[Felix]

a 4k and 5k crank are the same.

 

with the lifters i wouldn't bother changing to solids unless you want to make peak power at 8grand or more. all you need to do is get the rocker posts skimmed by the reduction in the radius of the base circle diameter when your cam gets reground to maintain hydraulic lifter preload.

 

that said, i have converted solid lifters in my 5k. by converted i mean they were hydraulic originally, but had the circlip removed and the guts ripped out. then the upper pushrod seat was dropped down to the base of the emptied out lifter. this cost zero dollars, and worked for at least 2 years in a mates club engine before they found their way into my street 5k which has been going strong for about 18 months now without a problem. i run a ported 5k head with 3k pushrods.

 

most of the guys who have converted to chev solids seem to have had problems of sorts (i can think of at least 3 guys offhand) and have had time off the road and had to spend extra $$$.

Edited February 26, 2006 by Felix

[Boost+k]

i wouldnt run flat tops AND a supercharger.. compression would be massive!!!!!

 

felix are the 3k rod the right size or do they require some work to fit?

i was gonna go out and buy some chev ones tomorrow but i thought they might be a bit on the heavy side..

 

when converting to solid do you block up the oil feed to the lifters? or replace the cam sheel with a 4k one?

[Rolla__Boy]

He hasn't got the hydraulic ones, that is the only reason he wants to put solid ones in it.

 

I have flat top pistons and a SC on my car :jamie:

[Boost+k]

hey rolla_boy what comp ratio do you have? how much boost?

 

does it pink much? mine does on 91 at about 9psi.. lol

Edited February 27, 2006 by Boost+k

[Rolla__Boy]

umm I am yet to put a boost gauge in this car, but I would say about 7 or 8 psi, maybe as much as 10.

 

My compression ratio is a mystery, this is a dead standard mostly stuffed 4K :jamie:

 

I use Ultimate 98, or Optimax, I assume by 91 you mean 91 octane fuel? If you do, then obviously that is why it pings....Mine would too.

 

On the higher octane fuel it doesn't ping at all.

[Felix]

felix are the 3k rod the right size or do they require some work to fit?

 

was a simple bolt up. i used 4k rocker gear. the 3k pushrods if anything are a touch to long and the adjusting screws originally just touched the underside of the rocker cover with a .400" lift cam. 5 minutes with a dremel remedied it.... i have a set of k (1100cc) pushrods (about 2.5mm shorter) to put in one day when i can be bothered.

 

when converting to solid do you block up the oil feed to the lifters? or replace the cam sheel with a 4k one?

 

no i didn't, neither did Pete who had the lifters in his engine. if you look at the normal k/3k/4k solid lifters you will see that they have large oil feed holes in them.

 

another alternative would be to get the lifter bores of a 5k sleeved down to take the earlier k/3k/4k lifters. this would be good as the earlier lifters are cheap, lighter and far more common.

Edited February 27, 2006 by Felix

[TRD ke70]

i have a set of 5K genuine toyota solid lifters for sale.

$80 for the set.

PM me if you're interested.