Ideas on an Engine build

all your DIY needs
User avatar
classicdat
Committee Members
Posts: 3259
Joined: Wed Apr 21, 2010 9:59 pm
aka: Vaughan
Location: Datsun Central, Christchurch
Contact:

Re: Ideas on an Engine build

Post by classicdat »

Sorry I got things backwards, the L14 'Crank" was what I was meaning with L20 slugs.
I guess I missed the point with that one, L14 block and crank/rods with the biggest L pistons you can fit after ultra sounding the bores to see how far you can go.
Don't take that calculator for gospel, it told me I couldn't bore an L24/26 block to fit L24 pistons, too big. Chem clean and ultra sound will tell you what you can do to your engine.
Datsuns from A to Zed
Bartman
Committee Members
Posts: 7303
Joined: Sat Jul 19, 2008 9:04 am
Location: Datsun City
Location: Christchurch New Zealand!!!!
Contact:

Re: Ideas on an Engine build

Post by Bartman »

If you can find an L20B block, you'l extra block height to enable the use of longer rods. More torque ftw!
Come to think of it, didn't the L14's also have quite long rods as well?
They don't call me the man with the rubber arm for nothing you know.............
unlimitedpower
Datsun Mad
Posts: 587
Joined: Fri Aug 01, 2008 8:02 pm
Location: Dargaville
Contact:

Re: Ideas on an Engine build

Post by unlimitedpower »

Block heights are the same on a L14 L16 and L18
I figure they all start out the same thing and the L18 is just bored larger than the L14 & L16.

L14 rods are the longest of the rods as far as i can tell (other than L13 but how many of those are there around).

I think the best option that i can come up with off the top of my head for a nice revy motor would be L16 Crank & Rods with Bored to fit STD L18 Pistons. Im guessing capacity will be around the 1700cc mark. maybe a little less

1:The L16 Rods are longer than the L18 rods and when combined with the L16 Crank should give the proper placement to the head surface. It'll just be an over bored (2mm) L16 in the end. 1.80 Rod Stroke ratio.

2:Im not sure how much is possible to mill off the tops of the L18 pistons cos with a L18 Crank L16 Rods and L18 Pistons theres an extra 2mm to worry about. And it takes the rod stroke ratio to 1.705


Now ive been reading up a little about rod stroke ratios what would be the best option of those to combination (providing the pistons could be milled down or won't cause to much of an issue. (im guessing the Comp ratio could be lowered on the 2: option with dished pistons) But it would cause issues with a closed chamber head.

Im probably confusing my self by trying to shove to much information in to fast so bear with me if i make some stupid comments.
User avatar
classicdat
Committee Members
Posts: 3259
Joined: Wed Apr 21, 2010 9:59 pm
aka: Vaughan
Location: Datsun Central, Christchurch
Contact:

Re: Ideas on an Engine build

Post by classicdat »

If you are going to buy pistons you could look around for ones with a higher pin height to allow for the increased stroke
Datsuns from A to Zed
Bartman
Committee Members
Posts: 7303
Joined: Sat Jul 19, 2008 9:04 am
Location: Datsun City
Location: Christchurch New Zealand!!!!
Contact:

Re: Ideas on an Engine build

Post by Bartman »

Theres a pretty handy piston catalog here-http://www.jccpiston.com/ If you trawl through you might find a piston that suits your requirements.
They don't call me the man with the rubber arm for nothing you know.............
unlimitedpower
Datsun Mad
Posts: 587
Joined: Fri Aug 01, 2008 8:02 pm
Location: Dargaville
Contact:

Re: Ideas on an Engine build

Post by unlimitedpower »

Bonus i never really thought of that. Not sure if its actually worth it or not though for the extra CCs
Plus it means i need to buy more parts rather than use up some of the things i already have. Will have a look through that catalog though.
User avatar
nzdatman
Financial Member
Posts: 418
Joined: Sat Jul 19, 2008 7:06 pm
Location: Taupo

Re: Ideas on an Engine build

Post by nzdatman »

I built an L18 with L16 rods and JE pistons. Decked the block so the pistons were flush with the deck.
Was a while ago but I remember L20b having longer rods and different big end bearings than L16/L18? Also has 6 flywheel bolts instead of 5.
User avatar
160jsss
Financial Member
Posts: 418
Joined: Sun Aug 03, 2008 7:41 pm
Location: Chch
Location: Kirwee

Re: Ideas on an Engine build

Post by 160jsss »

Did you ever get the parts of the guy from Trade me?
Violet - ??????
unlimitedpower
Datsun Mad
Posts: 587
Joined: Fri Aug 01, 2008 8:02 pm
Location: Dargaville
Contact:

Re: Ideas on an Engine build

Post by unlimitedpower »

Na i didn't unfortunately but im watching closely to see if they ever show up anywhere else or if i can track him down he still has a legal obligation to complete the sale.

Im going to avoid using anything thats L20B decided that i'll just throw together an L16 in an L14 block at this stage cos its cheap and i have all the parts then if WOF man doesn't like my L18 in there i'll put that in. Id fit all L18 crank and rods etc to the L14 block but i don't know how much it would cost to get it bored 2mm
Post Reply