We are going to rebuild our 1800.

I have a 100 questions but will start with a couple.

I have been told that 1800 internals are forged? Is this corect?

Can 1800 internals be spun to 7500rpms continually(providing all the right things are done)?

Should ARP bolts be used or is std ok for 7500rpms? (keep in mind this a track car,no street what so ever)

These may sound like lame questions but my knowledge lies in ford v8 engines, where everything is aftermarket forged, ARP and and big $$$$$

Thanks Dave

289,

I'm not calling you "KKK"!

I take it you mean an L18? If so, crank and rods are forged - like all L series, and practically all jap motors. Bit of a change from cast and sintered stuff, eh?

7500RPM should be OK, if (as you say), all the right things are done.

Rod bolts. Bit tricky. I'd say if you use light pistons (read: cast), you should be OK with Nissan items. For heavier pistons (read: forged), I'd personally prefer the ARP items. They're listed on Stewart Wilkin's site at $95 a set. Probably cheap insurance, considering the consequence of failure. Also, if you can afford forgies, you can afford ARP bolts.

Someone with experience of L series rod bolt failure would be a better person to talk to tho...

I can perfectly understand your hesitance coming from yank V8s. They're built to a price. Even the latest Caddy Northstar still uses sintered and cast bits in the bottom end.

Beef.

_________________
Recommended trading: datto-510

Snap!
Hey 289 .... perhaps I'm not weird! I figure it comes from a K289 motor (right? I hope).

Sorry, nothing add to add to your post though.

Cheers, Neil.

make sure the crank is true, have each individual journal machined to suit it's corresponding rod (not just one generic size), polish the rods and the crank and it should hold together no probs at 7500 with good tuning. if you let it detonate - well, no guarantees at all.

turn your attention to your cam, lash pads and valve springs at those RPMs though. you'll want dbl valve springs, a decent 72deg cam with a good 400thou lift and a light inlet porting to make the biatch BREATHE

then you'll need a carb(s) to keep up. at MINIMUM a jetted 32/36 DGV weber, then twin SUs, weber/dellortos, EFI, turbos, superchargers.... sorry, got a bit carried away there.

or you could just drop Baz a PM.

_________________
frankenstein projects R us.

The Republic of Western Australia -
Propping up the Nation's Economy since 1901.

if set up right an L18 will rev to 8500 no probs at all.
7500/8000 they are happy all day every day.
have had no probs with the std rod bolts but if you are familiar with the ARP bolts use them.

_________________
A little knowledge is a dangerous thing.
www.datsport.com

"R.I.P. Baz. 29 April 2022. Thank you for all your contributions to the Datsun community over the years. You will be missed." - OZDAT

It currently has twin 45dcoe's

So I thought they would do the job.

I was thinking of either one of the following cams


308321 IN.37/65
EX.69/33 282
282 232
232 .498"
.498" 3500/7000 Hot cam for street/race applications.


306741 IN.37/70
EX.78/45 290
290 255
255 .530"
.530" 4000/7500 High performance race

My v8 stroker windsor runs a similar cam rpm range to the first one,so I think a little 1.8 should do it easy.

From the two cams I have chosen can someone explain how many degree's they are?

v8 cams are refered to in degree's@.050lift.

This 72,74 degree thing has me confused.

http://datsport.com/Tek_Menu.html
this link will help you sort out the different cams.

with out going into detail a 72 cam is really 72x4=284 duration.

race engine L18 min cam. 47 77 82 42 0.527" lift.
312 duration with 0.620" lift is about max you can go.
48mm webers with 42mm chokes, thats if you want good grunt at 7500.

_________________
A little knowledge is a dangerous thing.
www.datsport.com

"R.I.P. Baz. 29 April 2022. Thank you for all your contributions to the Datsun community over the years. You will be missed." - OZDAT

Baz wrote: What is it that you have to do to make an L18 able to rev this high? Does the standard engine have particular weaknesses?? What parts need to be modified? If Baz or anyone else could post some discussion or info on the theory behind a high revving L18, that would be great. thanks,

Tom.