Jump to content

240z su's on a l18??


Recommended Posts

so a friend of mine is given me a set of stock 240z su's for free and also a mani that i can use to bolt the su's onto my l18 and i was wondering would this b to much carb for my motor if i got them re-jetted?? the l18 has a peanut head flat top pistons and also a cam out of and l20.. i was thinking maybe with a bigger cam i would b able to use them?? or should i just not bother running them..

Link to comment
  • Replies 17
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

I think it's a great idea. The SU is a constant velocity carb and will only open up as much as the engine can handle. You will need to monkey with the needles and jet sizes. I think Jason on here has SUs in his car see what size he is running as a base start.

Link to comment

well i have seen some people runnin 45's on webers and mikunis so i thought mayb that would b a good start.. as for the cam shud i try to find a bigger cam or run the l20 cam thats in it.


"i know nothing about cam specs or duration or anything of that so any help would b greatly appreciated"


datzenmike idk jason or jason name on ratsun so cud u give it to me so i could shoot him a pm??

Link to comment

I have toyed with the idea for my L20B, but I still think that's a lot of Air/Fuel for a 4 cylinder.


Here is some good reading that supports my opinion: http://www.jetlink.net/~okayfine/su/zsus.html


Not saying it won't work, but I still think it's a lot for the 'Little L'.

Link to comment

The L16 and L18 SSS's from Japan ran a 38mm SU. The 46mm SU's on a stockish L18 should work fine, a little rich, but, you could lean them out if need be. I run my 38mm's dry on long, hard pulls on my L20b with a Shadbolt 445 cam.


No jets in these guys, just one big honking needle up the middle and as Mike says, constant velocity. The 38's that I run are OK for milage and give decent torque at low to mid range revs, but, crap out at higher revs if it's sustained for any great duration. The 46's should help with that part though ... Try it out and let me know. I've got a pair of 46's waiting on my manifold to be machined for my new LZ22. (Thanks Mike!)

Link to comment
  • 4 weeks later...

so i put the su's on my car but i have to run a throttle cables so i can use them. im plannin to go to the jyard to c if i wat i can come up with for cables. anybody have any pointers of wat i need to b able to pull this off?? is there a different direction that i should go with running these su's?

Link to comment

try contacting steve epperly at Z therapy as he does or knows of this mod. I personally think and have a strong feeling the Z su's in your current motor state will be too much carburetor. If you had a bigger displacement motor I would use them.

Link to comment

so this past weekend i put the su's on and tried to think of a way to link them by shortening the linkage that came on the manifold but ran into problems with that idea ... i was wondering if anybody else has any ideas on how i can have the su's open together??


i was thinking of just welding a tab to connect the to su's so the open simultaneously but do i need to b able to have adjustment between the two carbs???

Link to comment

Ok here ya go. I used a part [painted aqua] off some roadster carbs i have. had to cut apart & weld back together but it works. The black bracket i made & bolts to the exhaust manifold & then used another piece to keep the black bracket from flexing. True Ratsun low tech. crafsmanship at work :D


Link to comment

thanx pacific ill try to run my throttle cable that way but i forgot to mention that i have the round top su's an they open the opposite way.. :( but i can use still some of the ideas u should me. and u know the lil piece that the aqua thing is linked to... the one with the balls at each side of it?? i had to shoten mine and its still to long to connect the two su's... can i just wel a peice of metal right there to connect them??

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.