5k Cam Info.

[Old fella]

G`day all, I just scored a 5k to drop into my ke70 and need to know some stuff about the cam and rocker setup. I have a few 4k hotty cams and would like to run one in the 5k, but need to know if I can simply run 4k cam, lifters, pushrods and rockers rather than having to get a 5k cam reground.

Thanks for any info in advance. Old Fella.

 

Thanks heaps guys. What a wealth of info. I`ll probably go with getting the 5k cam reground to the same profile as the one that I`m using now. It seem s to be the simplest method and after a bit of research I`ve discovered that the hydraulic lifters will be suitable for the rev range that I have been using.

Again, thanks heaps for all of the info.

Old Fella.

Edited March 15, 2010 by Old fella

[Taz_Rx]

Cams and rocker gear is interchangable, but the lifter and pushrods are not (5k lifter bore is bigger).

 

If you want to do a solid lifter conversion then just get yourself some chevy lifters and Datsun A12 pushrods.

[philbey]

you'd also be wise to check that your rocker post heightss match the camshaft lift.

Edited March 14, 2010 by philbey

[67Rolla-Ken]

Yeh, I did the 3K rocker assembly, Chevy lifters with A12 push-rods and had to get spacers under the rocker posts. Wasn't hard though, just sent a post to a fab shop and got them laser cut (cost around $100 from memory).

 

I wasn't 100% sure that the push-rods I was sold were A12's so as I hadn't heard of anyone else on here having this problem I assumed wrong push-rods was the explanation.

 

Never new the extra lumpy cam might change the lift height >|

Edited March 14, 2010 by 67Rolla-Ken

[philbey]

Never new the extra lumpy cam might change the lift height >|

 

as in you didn't realise the cam grind would increase the lift and that's maybe why your pushrod length's are out?

[67Rolla-Ken]

As in I'm still mechanically challenged... but learning.

[camerondownunder88]

The Datto A12 push rod is one way...

 

You can still use your 4K push rods in a 5K I did.

 

Buy 3F Toyota solid lifters.

geta set of 4K-C push rods.

Get your rockers and the 3K TRD manual. If you re-work the rockers to TRD spec the 4K-C push rods fit in. Then you can use all Toyota parts and if you break a rod PLENTY of 4K's around.

 

Also.

 

From my use of a 5K in a car with stock cams, from all K motors (not all K motors run same grind) and a few hot cams. They come on a bit earlier than other K motors about 500RPM.

 

My Local cam shop all his grinds are listed for 3K for the sprint cars that have to use 3K's. He has designed all these cams for 3K. Now I find all his grinds the rated RPM power range max RPM etc all come 500RPM earlier in a 5K so also keep this in mind when chosing a cam if the cam is listed for a 3K expect it to behave different in a 5K.

 

Cheers

Cameron

[Felix]

when chosing a cam if the cam is listed for a 3K expect it to behave different in a 5K.

 

Definitely.

 

The chev lifter a12 pushrod combo works on a 5k with a 3k head. If you use the orig 5k head the pushrods are too long as the 5k heads are not as tall.

[camerondownunder88]

Should note my way of making a solid lifter 5K is witha dished piston head.

 

 

I did work out another Toyota push rod to make this work with a flat top piston head but can't remember it off top of my head.

 

Cheers

Cameron

[coln72]

I just ran a reground 5k cam and standard lifters. A lot less stuffing around than getting lifters/pushrods/rocker posts right.

 

A Wade 169 grind ran well in my 5k

Edited March 15, 2010 by coln72

[19914afc]

Should note my way of making a solid lifter 5K is witha dished piston head.

 

 

I did work out another Toyota push rod to make this work with a flat top piston head but can't remember it off top of my head.

 

Cheers

Cameron

 

3L engine from a landcrusier??

[camerondownunder88]

...

 

don't belive me... Go measure them for ur self then

 

Also another thing came to my mind.

 

Some chev solid lifters do have the oil hole drilled in the side differently to others. (think It was lower). If you use that type in a 5K what can happen is the oil hole in the block for supplying high pressure il to lifters will be open and you will find your engine wont make oil pressure and lifts have a LOT of oil in them.

 

BUT 3F lifters the Toyota part number cross references to the solid lifter used in 5K's that were factory solid lifter. So the oil hole is in the right position so you will get oil pressure etc.

 

But I think it has just een me and one other member that experienced the oil pressure issue so not common but be warned it can so if you run into that problem just change lifter.

 

Cameron

[19914afc]

...

 

don't belive me... Go measure them for ur self then

 

Also another thing came to my mind.

 

Some chev solid lifters do have the oil hole drilled in the side differently to others. (think It was lower). If you use that type in a 5K what can happen is the oil hole in the block for supplying high pressure il to lifters will be open and you will find your engine wont make oil pressure and lifts have a LOT of oil in them.

 

BUT 3F lifters the Toyota part number cross references to the solid lifter used in 5K's that were factory solid lifter. So the oil hole is in the right position so you will get oil pressure etc.

 

But I think it has just een me and one other member that experienced the oil pressure issue so not common but be warned it can so if you run into that problem just change lifter.

 

Cameron

 

 

what lifter would you recommend the crusier ones or the chev ones?

[camerondownunder88]

Alot here run 3K head with the A12 push rod and chev lifter. Works reliable.

 

If you run a dished piston head Id go for the 3F cruser lifter. AGAOIN I HAVE A DISHED PISTPON 5K RUNNING THIS SETUP NOT A 5K with FLAT TOP PISTON HEAD.

 

The 3F lifer is a lighter lifter and if you can source some dished piston 4K push rods no mods need doing to the rocker gear it is bolt in go. So for me id go cruser lifter.

 

But if sourcing A12 rods is not an issue for you go chev.

 

As dished piston 4K are not common so there push rods can be hard to get. So that leaves moding 4k-c and stock rocker gear to run 3F lifters that might be hard for some so really from a performance view

 

Id go 3F lighter lifter etc etc.

 

Easier conversion go chev. UNLESS you have 4k dished piston push rods as then well it is all bolt in.

 

Cameron

[Felix]

Easiest thing to do is pull out the 5k cam and get it reground. About the biggest issue you can run across is the possibility of needing to get the base of the rocker pedestals milled down if you have insufficient hydraulic lifter preload.

 

A point to keep in mind if you use a cam laying around originally from a flattop 3/4k is that they have a wider rear cam bearing journal than the 5k (or dished 4k) cams. The wider rear cam journal on the flattop cams can press against the welschplug at the rear of the cam tunnel when you put it in a 5k and cause problems.

Edited March 15, 2010 by Felix