vrmilionzx Posted August 17 Share Posted August 17 (edited) Hi All, I have been restomodding my very first Z (early 260), and probably did things way out of order. Got the car (rusty, needed work, half disassembled but told the engine would run, gas tank in the hatch, no airbox, etc) and it went straight into body and motor work/build. I wish I had gotten it running first, to appreciate how it ran and handled, but the rust gave me pause, so I went the full resto route first. All that said, this is not my first engine build, but my first L series and first car with carbs. Now that it's done, I need to work out what's keeping it from running better. The motor is a frankensteined together L28 (F54 block, N47 head), roughly 9.2:1 CR based on (Priddy - Cometic) head gasket and (flat top) piston combo. Steve Bonk stage 1 cam, stock hitachi/SU carbs (rebuilt with SM needles and rebuild kit from ZTherapy), cleaned up balance tube with N36 intake manifolds. Early 280zx close ratio 5sp trans,3.9 R200 rear end, stock (l28 appropriate) clutch/flywheel combo. The shop that did the body/resto work dropped the motor in, and got it running, but it I'm pretty sure it should be running a lot differently (read: better). It's idling around 5-600 rpms, lumpy, and feels pretty underpowered considering it's a light car with a modded L28. Did the break in drive in which I didn't take it over 5k RPMs, ran it decently hard with solid acceleration and engine braking across gears to seal the rings, did the oil first oil change, and all that jazz. This is where you come in - I'm hoping that someone here who knows the L series is up for a half day of walking me through confirming that the (mechanical) timing is set right (the easy part, I've done this with my other cars but appreciate a second set of eyes), then wants to help me make sure I don't do anything stupid trying to set the idle and balance the carbs. Looking to learn from one of you gurus so I'm not messing up a fresh motor in a fresh car. Anyone in the Bay Area want to come to Novato and help me out in exchange for beer, lunch, and the opportunity to mock me while you help me learn this motor? Thanks in advance! Robert Edited August 17 by vrmilionzx 1 Quote Link to comment Share on other sites More sharing options...
Leon Posted August 19 Share Posted August 19 Hey Robert, sounds like a rad build! You should post some pics of what you're working with. I'm in Burlingame but also have three little kids so Novato is no-go. Unless you're able to bring the car down here in which case I'm happy to help! Otherwise, maybe reach out to the folks at ZONC (Z-Owners of Norcal) via their Facebook page to see if you get any action? 1 Quote Link to comment Share on other sites More sharing options...
vrmilionzx Posted August 20 Author Share Posted August 20 Hey Leon, Thanks for the reply! Pic attached for attention - you can probably figure out which are before vs after . The interior isn't all there yet, so not sharing that mess, still troubleshooting some stuff inside. Now that the alignment is done, I'm not opposed to bringing it down your way. Still working on break-in miles (it's at 78 total), so not trying to do any LONG drives just yet, but that might be manageable. Just have to figure out timing, and tooling. I don't have an empi style vacuum tester just yet, do you? I'll also be at Cars and Coffee (Vintage Oaks) and Pre-Stage (Marin Civic Center) in September, if anyone will be there! Robert 2 Quote Link to comment Share on other sites More sharing options...
Leon Posted August 21 Share Posted August 21 Very nicely done, love it! I'm on my second early 260Z so I've got a soft spot for the S30 family middle child. I do have a syncrometer, I've been tuning sidedraft Webers on-and-off for close to 15 years now. It's been some time since I've played with SUs but they're pretty simple devices comparatively. BTW, have you checked your valve lash? This is super critical to do on a fresh head. The lash can change considerably and quickly over the first few hundred miles as the valves break into their seats. I did my motor break-in while driving the car to JCCS back in 2013 and by the time I reached SLO, a cam lobe was already wiped. My best guess is that it was a result of the aggressive wipe pattern of my cam combined with a rapid reduction in lash during break-in. I'd love to pop by Pre-Stage again some time as well, I've only been once and that was on a rainy day last December. Maybe I'll even have my side mirror repainted and fresh door cards mounted by then... 2 Quote Link to comment Share on other sites More sharing options...
vrmilionzx Posted August 21 Author Share Posted August 21 I've not checked the valve lash yet since the break in drive. The shop that had it said they did, but I think after the last 70 miles or so it wouldn't be bad to re-verify that everything is where it should be. Nothing wrong with triple checking, I'd really like my engine to last (and not trash my cam)! Quote Link to comment Share on other sites More sharing options...
vrmilionzx Posted Sunday at 04:01 AM Author Share Posted Sunday at 04:01 AM On 8/18/2026 at 5:37 PM, Leon said: Hey Robert, sounds like a rad build! You should post some pics of what you're working with. I'm in Burlingame but also have three little kids so Novato is no-go. Unless you're able to bring the car down here in which case I'm happy to help! Otherwise, maybe reach out to the folks at ZONC (Z-Owners of Norcal) via their Facebook page to see if you get any action? City& Local Guides You've got a PM! Quote Link to comment Share on other sites More sharing options...
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