Hey people of Rollaclub,

I am in urgent need of some info/ personal experience when it comes to combining a 5k block with a 4k head.

At the moment I'm in the middle of my 5k conversion which has involved rebuilding a 5k bottom end, pulling the 4k and 4 speed and then transferring all of my 4k ancillaries and head to the 5k.

I didnt have the 5k head so i did loads of research and ended up swapping to 5k shallow dish pistons so that i could just run my 4k head.

 

However- i wanted to stay hydro and still had the lifters, pushrods and rocker assembly to do so, but the pushrods are too short! They were meant for the shallower 5k D-dish piston head :hammer:

 

SO, at the moment the combo is assembled with 4k solid lifters, pushrods and rocker gear.

 

My question is whether or not you can run this combo (i have a reground hydro cam). The only thing that seems out of place is the slightly smaller diameter of the 4k solid lifters (they are semi loose).

 

Will this work??? Other than this the 5k is ready to go in!

 

THis is my first engine build/ conversion and i need my car for work on monday so any help is appreciated! URGENT

Thanks, Ro

Yeah i'm pretty sure 4k lifters are too small for a 5k block..

 

I'm guessing you need the chev solid lifters and datsun a12 pushrod combo

 

Or did you want to stay hydro? Kinda got lost in all the words

4k lifters in 5k wont work

 

http://www.rollaclub.com/faq/index.php?title=Tech:Engine/K_Series/5K-C/5K_Hydraulic_To_Solid_Lifter_Conversion

 

 

or if staying hydro get some coustom pushrods

 

 

Monday? find a spare running K and drop in while you get the 5k sorted

Edited September 8, 201214 yr by tojo2

Yeah, there's oil ways going to those lifters, if you run them you'll probably not have oil pressure to other parts of the motor and there's a chance you'll fry it. The above option is probably best. You'll probably have a hard time finding the push rods you need.

Yeah thanks guys- it is as I feared. So keen on being able to see the fruits of my labour + I owe a lot of people their parts back!

I'll look for that lifter/ pushrod combo. Any recommendations for where to source these parts from? Locally we have A bursons, sca, Scott's, repco and an engine builder.

You need solid chev 202 lifters, most of those places only sell the hydraulic ones I found called 'anti pump' lifters. I got a member on here Stu, 'kickn5k' to sort me out with the correct lifters

I have both a set of lifters and a12 pushies available for sale.

Don't know about solid lifters on the hydro cam though!

....but I have a cam available too! Lol

 

Btw I assembled a 5k with 4k head, a12's and chevs last night!

Why not just run the 5k head with with the 5k pistons? I'm running the shallow dish pistons, just need a big ass cam grind.

 

Alternately you could just get an engine builder to rip out a couple of cc from each head chamber.

Edited September 12, 201214 yr by philbey

Well I bought the 5k block without the head, and haven't been able to find a 5k head. Do you reckon I'd get away with the shallower head on the shallow pistons? How did you bring the compression down, and what did you get it down to? I have a 25- 65 cam (tighe 104). I will have another read of your build thread! Thanks philby!