moritz55

Hello, since I purchased a can of SEM Chip Guard -39804, I tried it on the wheel well inside edges. They get chipped up pretty bad and I'm always touching them up so I figured I had nothing to loose tyring it out. So .. my process steps were for the most part just as described on the spec sheet. SEM Tech. Data Sheet: http://semproducts.com/images/tech_files/CG%20TDS.pdf Sequence: 1) Cleaned surface from dirt and road film with dish wash detergent, water & spong. Rinse clean and thoroughly dry. 2) Using Scotch-Brite Pad (Gray color ones), rather than 400 grit Sand Paper, I dulled the surfaces enough to prep for base Coat Paint. 3) Then I sprayed 2 light coats of my "Green" Body Base Coat paint. I allowed 10mins between coats and then 20mins for it to dry. 4) Most important part when using the SEM Chip Guard - for maximum gloss and clear/smooth finish: ......... a) Hold can ~20 inches away. Calibrate your spray distance with a tape measure just to be sure you are far enough. Too close leaves a lumpy surface. ......... Start by spraying the SEM Chip Guard OFF the surface on paper masking area until the flow is steady/uniform keeping ~20 inches distance from the surface. I applied two passes so it was uniform and had a wet look. ......... c) Wait about ~5 mins, then repeated above applying two passes for another wet coat. Then repeated after another 5mins and did a 3rd application. 5) Drys to touch in 30mins - pretty quick. Pulled tape off immediately and no pulling or sticking to the tape edges. Photos could have been better, anyway they are ... 000/001 - before, 002/003 - scotch-brite scuffed, 004/005 - green base coat applied, 006/007 - After SEM Chip Guard applied. Overall .. it' looks pretty good. The SEM coating is defnitely heavy. We'll see how it holds up...

Thanks .. I think you convinced me 3M Tape Chip Protection is the best approach for both function and transparent visibility since it's virtually unoticeable. I'll shop around and try to find an expert installer locally near Newburgh or Beacon New York. Do you happen to know if there is a "Kit" with precut pieces for installing or is this a custom job? Many thanks...

Well, looks like the best bet is the 3M Clear Film based on Palosfv3. Even though the SEM Chip Guard can be easily applied. So .... ==> It sounds like 3M Film (tricky and very, very permanent and tough to remove) is the best bet. It's used on new cars today - clear and almost not noticeable but really should be applied by experts. It's also expensive, not to mention labor costs. ==> SEM Chip Guard is easily applied. Very flexible in use for small or large surfaces. The instructions say 3 wet medium-coats with 5-10mins between. The end result may not be robust/thick enough for the long term. Surface may not be as smooth as desired. I think I'll expertiment with the SEM Chip Guard on the inside wheel well fender lips. They get chipped up pretty bad and if the material doesn't go on as "Clear & Smooth" as desired.. It's not terrible. I can pick up a 16oz can for $19.00 locally. Anyway I won't be risking the side running board area and lower rear fenders. I'll take some before and after photos to document my approach and share it here. In the mean time - maybe we'll get some info with photos of the finished product on cars from fellow Zcar owners that have used SEM Chip Guard a while ago so they can comment on the effectiveness on reducing chips. Stay tuned ....

Hello, I'm looking for advice on an SEM product: Clear Chip Guard - Aerosol 39804 . I'm getting my 240z ready for summer driving and this year my goal is to try something that prevents all the stone chips along the running boards and rear fender from dinging up the paint. I must spend at least an 1hr per month touching up stone chips. With my tires on 7.5" wide rims and driving on clean highway and smooth roads, I still pick up quite a few small stone dings in the paint - in some cases down thru the primer to the metal. Questions: 1) Has anyone tried using the SEM Clear Chip Guard Aerosol - 39804? SEM Tech. Data Sheet: http://semproducts.com/images/tech_files/CG%20TDS.pdf 2) Does anyone know a better product or technique for adding a clear protective stone chip coating? While also looking very good ... For a 240z, there are several options for coating the running boards and rear fender under the bumper such that the "Line" or "Boarder" is not very noticeable. In fact if I follow the "Crease" from the Front Fender-to Door-to Rear Fender line - it would not be noticeable as long as the Clear Chip Guard coating is smooth. (See the photos - the crease is about 8 inchs up the bottom of the running board). Anyway - I'm looking for advice before I get into something I'll regret much more than living with the hours of stone chip touch-up I have today. Many thanks...

I used Tokico HP's for my 73 240z. Bought them from MSA - the fit nice and I like the ride. I also bought a set of Ebach's ($169 on sale) for a 280z ... these springs enabled my car to sit at Stock Hieght. Here is a link a while back, go to post #18: http://www.classiczcars.com/forums/showthread.php?t=36014 Note: I could not get rear Arizona Z coils for stock height as they were out at the time. Maybe they have them now - A-Z did have stock height coils for the front. Good luck...

Here's what I did to get my 240z to Stock Height with Tokico HP Shocks in the links below. Results are a tight ride with nice height. I used Eibach 280z Coils (from MSA) .. rears gave me stock height out of the box.... Fronts, I cut 1 full coil off to lower the front 1/2" or so from stock height. The photos in the link reflect the height after ~20miles put on the car. I have added ~150miles since doing this and the height has still remained with 1/8" of shown in the photos. Rear down 1/8" slightly and fronts remaining as is in the photos. Read post #4: http://www.classiczcars.com/forums/showthread.php?t=36748 Read post #18: http://www.classiczcars.com/forums/showthread.php?t=36014 Good luck and hope this helps.

Thanks oldhemi for the feedback ... I did not see this till now. ==> I measure stock height from center of wheel arch to floor. Good luck..

12/27/09 ... I took the car out for nice 50mile ride this past weekend mostly highway. We had a warm Sunny day ~45F in New York and roads dried up after a nice rain all night. The ride was simply terrific, soft enough for bumps to be felt, definitely not bone jarring... nice and firm. I got it up to 85-90MPH for a period and the car did not have that "floating" feel, it was tight to the road. Also when accelerating hard, I did not feel any "squatting". The Eibach 280z coils with 240z Tokico HP shocks from MSA in rear make it real firm. With 1 adult (~175lbs) rear only dropped ~1/4-3/8" .. not much at all. The car settled a bit now with 70miles on it. My final height with 195/70/14 tires from ground to wheel well arch center: Front: 26-1/8" (1/2" lower than stock.. 1 top coil cut from front 280z Eibach coil). Rear: 26-1/2" (stock height, 280z rear coil installed as-is). Note: I Corrected for my tire size (205/65/15) which has a 3/8" larger radius ==> thus higher from the ground. Any way ... thanks for the encouragement...... Happy New Year to all !!

Thanks for the response Adam. My R200 differential has about 80k miles on it as it was pulled from a 1982zx. I'll keep and eye and ear on it... I did take the car out this past Sunday for a 15mile run, city and highway and it ran quietly. Real smooth even with the 25F temperatures, no snow .. just cold and dry conditions. Many thanks ...

Well .. I finally took the car out last night after changing my engine oil as I get it ready to be tucked away for winter. Put about 15miles on it .. city & highway. I noticed immediately how much firmer the handling and ride was.... I like it a lot. Very responsive on the front when steering sharp and simple cornering seems tighter and not as mushy... the rear of the car does not rock or roll is my best description. Even with my tires 8lbs over inflated (~38psi) as I keep them hard for winter storage to minize flat spots, the ride is very comfortable. Sitting in the car I noticed immediately real good front visibility (less hood) becase the hood front is a tad lower combined with my rear not saging when sitting in the car - it's nice and firm. With the Eibach coils and having 2 adults in the car - my rear only drops about 1/2" from Free Height position. Previously with original stock coils (~94 lb/in spring rate after 37yrs) the car would squat between 1.25" - 1.5" with 2 adults seated, thus squatting almost 2" lower than Stock Free Height. Today it only squats about 1/2" lower than Free Stock Height with 2 adults.... I like this. When driving with the new shocks and coils I feel the bumps, but they are actually very dampened and actually better than before. My rear bumps were so hard previously on the car I'd hear bad rattles, now they are reduced even with extra hard tires. Attached are the Instron Load curves (it's posted in earlier replies above) for the Eibach Springs I used; 260z/280z set of coils. Fronts are a constant spring rate where as rears are a progressive spring rate. In general I'm really glad I spent the time and went down this path. Especially with the wider tires, my negative camber in the rear should be less as well. I'll get the front aligned in the Spring '10 and get rear alignment data to see how much my rear camber really is now. My other post with some 280z Eibach / Spring data for a 240z: http://www.classiczcars.com/forums/showthread.php?t=36748 Hope it helps others... Many thanks Eibach 280z Spring-Data.doc

MANY THANKS ... Beandip !!!!!! I searched the site, resurrected this older post as it helped me get through a strange noise from my rear end. My Sceanrio: I have never had wheel bearing are differential noises before. Anyway after I completed installing new coils and shocks on my 1973 240z and was anxious to test drive it! I also greased the U-joints along with the other front end fittings as typical maintance for winter storage. I finished the job, test drove the car and when turning left I hear an almost grinding noise from my rear (right side). Went back home, I checked all the drive shaft bolts - all are secure - tested it again and the same "grinding" noise from my right rear when turn left?? Found this link and did the following on my R200 differential: 1st) Drained my differential, the oil was terrible, very black and thin, no real viscosity felt between my fingers. I did find a one metal sliver on the plug and could see very small metal specs on the rag used to clean the plug under bright lighting. The plug debris wasn't terrible as I've seen this before. The sliver looked new - most likely from my recent "grinding" test drives. I let the oil completely drain to get as much out as possible. 2nd) Refilled the differential with Royal Purple 75W90 since it's supposed to be great stuff. Also a lot of positive words in this website. With the car up on jacks and the 5spd in neutral I rotated the rears - they turned freely and smoothly. No slop in any U-Joints or anything out of the ordinary. I also put the 5spd in reverse and turned the wheels - nothing strange here also. Rotated one and the other side rotated in the opposite direction smoothly. 3rd) The TIP from this original link above .... Lastly - using a 3lb mallet and socket extension, I tapped the differential drive hubs "INWARD" toward the center of the differential thinking maybe I pulled them out a bit when I replaced my rear shocks and coils. I did this about four(4) times on each side hard enough with a 1/4 swing of the mallet. When finished - rotated the wheels to assure no strange grabbing or noise - all was smooth. Then test drove the car and the noise was gone. The rear end almost seems quieter as well, maybe it's me? I'm thinking the New Oil (especially Royal Purple) along with tapping the drive hubs - may have un-stuck the slip plates? I was all ready to line up a wheel bearing replacement job. and maybe I will have to in the future, but for now it seems fine and I'll watch this. Right now the car is winterized and will have to wait for spring - since it's pretty cold (20F) and snow coming. Anyway - this link and website was a huge help. Thanks BEANDIP !!!!!!!!

Well for those that may be interested in getting a 240z to stock height with a performance/progressive spring set. I finished the installation of my Eibacks with MSA 240z Tokico HP shocks. I used the Eibach 280z coils for a '74-'78 260z/280z from MSA as I mentioned above, Fronts -001 and rears -002 as described with the kit. They lower the 260z/280z about 1" ... but yield stock height when used on a 240z, yet with a firmer and better handling ride My tires are 205/65/15's .. 3/8" higher than the stock tires (195/70/14) so I've reduced my measurements to account for this slight increase due to tire height... ==> Front true height (ground to fender tire arch) is: 26-1/8" (~1/2" lower than stock). (I cut 1 full top coil off the Eibach -001 to lower it slightly from stock level). ==> Rear true height (ground to fender arch) is: 26-1/2" (~1/2" higher than stock) (Rears installed as-is from Eibach -002, new MSA strut insulator for 240z and new MSA urethane spacers for 240z). I really wanted my car to sit with the front 3/4" to 1" lower than the rear to keep the nose down when cruising on the highway. It turned out pretty close. The photos below reflect my recent installion with just about 10miles on the car. It may settle a little more over time.

Well for those that may be interested in getting a 240z to stock height with a performance/progressive spring set. I finished the installation of my Eibacks with MSA 240z Tokico HP shocks. I used the Eibach 280z coils for a '74-'78 260z/280z from MSA as I mentioned above, Fronts -001 and rears -002 as described with the kit. They lower the 260z/280z about 1" ... but yield stock height when used on a 240z, yet with a firmer and better handling ride My tires are 205/65/15's .. 3/8" higher than the stock tires (195/70/14) so I've reduced my measurements to account for this slight increase due to tire height... ==> Front true height (ground to fender tire arch) is: 26-1/8" (~1/2" lower than stock). (I cut 1 full top coil off to lower it slightly from stock level). ==> Rear true height (ground to fender arch) is: 26-1/2" (~1/2" higher than stock) (Rears installed as-is from Eibach, new MSA strut insulator for 240z and new MSA urethane spacers for 240z). I really wanted my car to sit with the front 3/4" to 1" lower than the rear to keep the nose down when cruising on the highway. It turned out pretty close. The photos below reflect my recent installion with just about 10miles on the car. It may settle a little more over time. Good luck...

I don't know about the eBay seller but in my '73 240z which has a 1982 5spd 280z transmission and L24 engine, I do have a Fidanza Aluminum flywheel installed. My clutch kit is different as I have a Center Force Dual Friction clutch. I'm pleased with both. The clutch is 2 yrs old (~3000 miles on it) and the Flywheel is 12yrs old (~15000 miles on it). I had the Flywheel resurfaced when the new clutch was installed. Anyway .. hope this helps. Good luck.

I replaced mine in my '73 240z. They are different between models. Here is the MSA 70-73 240z cable: http://www.thezstore.com/page/TZS/PROD/30-7500 Here is the MSA 74-76 260z/280z cable: http://www.thezstore.com/page/TZS/PROD/30-7501 I'd call MSA and ask if the 74-76 260z/280z cable assembly would work for your 77 280z. They are very knowledgeable. When I replaced the '73 240z assembly from MSA on my car it was the entire assembly and well worth the money. It included the bracket, grommet and handle .. it was a simple drop in allowing me to re-use the screws. Anyway ... good luck.

Bobm , I am in the process of getting my 240z back to stock height with new springs and shocks. The only Eibach "Performance Style" springs that get your 240z to stock height - however with a performance ride is if you use 1974/78 260z/280z srpings on your 240z. Go to the bottom of this link, some of my observations: http://www.classiczcars.com/forums/showthread.php?t=36014 Arizona-Z is out of Stock Height Rear coils, so I'm installing the Eibach 260z/280z set from MSA. PN 6303-001 (front) and 6303-002 (rear). The ride will be firmer, but the height will be perfect on the Rears, where as the Front will be possibly 1/4 inch lower... I'm cutting 3/4 of a coil from the fronts to get my car to have the front drop about 1/2" - 3/4" lower than stock level. Here are the spring loads & lengths for stock 240z New Springs: Front Load per spring: 562lbs (driver side) ... 604lbs (passenger side) Front Spring Stock Length at Load: 8 inch (both sides) Front Spring Constant: 83lb/in (both sides) Rear Load per spring: 635lbs (both sides) Rear Spring Stock Length at Load: 8.4 inch (both sides) Rear Spring Constant: 104lb/in (both sides) My original Rear springs after 37yrs of use .. ran 5/8" lower (7.78" loaded at 635lbs) so the overall spring constant degraded about 10% to 94lb/in (not to bad for 37yrs). Anyway Eibach's spring PNs are: 6303-001 Fronts , 6303-002 Rears for a 260z/280z .. that I am using on my 240z to assure close to stock height, yet have a firmer ride. Hope this helps and good luck.. Eibach 280z Spring-Data.doc

Thanks Arne, I've been checking around and have not been lucky on finding Euro Stage I 's . Now that I have my car apart, and found my rear sat low by ~5/8" becuase of compressed 37yr old strut insulators and rubber spacers - I'll replace them with MSA new parts. Also the driver rear had a 280zx Tokico shock in it (HZ3038) vs the 240z HZ38016 correct one. Not sure how a 280zx shock on the driver side will make a difference - but the driver side sat 1/4" lower than the passenger side. With New Rear HP Tokico's, along with the New Eibach 280z Rear 6303-002 progressive springs - I'll get stock height or maybe 1/4"-3/8 higher ride once it settles in for me. It will be firmer also since Eibach's are at 200 lb/in compressed to 8.5", the full 635lb load ride height for the 240z. What I'll do next is drop my Front by ~1/2" by cutting the Eibach 280z Front coil 6303-001 just a bit (I'm thinking 1/2 to 3/4 coil cut off. Today my front sits at stock height - but I'd like to drop it ~1/2. I'll let you know how it turns out as I try to finish this up this week. Many thanks......

Well, I thought I'd update you all on my search to find Stock height Rear springs for my 240z as I try to raise it 1.5" from it's current position (it's low ~1" from stock height). I bought Eibach performance springs from MSA for a 260z-280z ('74 - '78). Fronts: 6303-001 (10-5/8" Free Length with 173 lb/in spring constant) Rears: 6303-002 ( 12-1/2" Free Length with Progressive rates 150-200+ lb/in) I then had a lab run Instron compression data for me and thought I'd post it so anyone can use this for other installations and compare to their current or stock springs. Eibach's 260z/280z performance springs get pretty close to stock height for a 240z. Here's my summary on how to achieve Stock Coil Springs off-the-shelf since Arizona-Z is out of Rear Coils: For a 240z Rear Stock Height - the Eibach 280z rear progressive spring achieves 8.5" compression at 635lbs full load. For a 240z Front ~Stock Height - Eibach 280z front 173 lb/in springs drop the front about 5/6" to 3/4". This actually brings the 240z nicely level such that the front is not slightly higher than the rear as designed. In my case I'm now in the process of taking my rear coils and struts apart. As I did this - my Rubber Spacer and Strut Insulator were pretty crushed... to a point where they were 5/8"-11/16" lower than stock design compared to new ones from MSA. Next step - I'll take my 37year-old rear coils and have them Instron compression tested to see how they compare to the original 103 lb/in spring constant and thus ride height. I'm hoping I'll see another 1/2" lower ride height at 635lbs load which explains why my car rear was ~1" lower than stock. If this is true I'll be installing all stock parts (New Urethane Spacer, New 240z Srtut Insulator) with the 280z Eibach 6303-002 Rear Srping and New Tokico HP Rear shocks. Hope this get's me 1"-1.25" increase in rear height. Anyway .... stay tuned. Eibach 280z Spring-Data.doc

Thanks Carl.. I've not been to lucky finding a new set of coils that will fit the perch of a 240z/260z/280z and give me 1inch more of stock height in a 240z application. So I can certainly use advice.... so here's my logic: Since the 260z/280z weighs more than a 240z by roughly 100lbs on a rear coil the compressed length of the stock 260z/280z coil you reference is ~9.6" . Therefore if used in a 240z the compressed height would be 10.4" which is 2" higher as you suggest. My thought in trying the 260z/280z Eibach coils which have a 13.25" free length in the rear is as follows. They drop a 260z/280z by ~1" bringing the compressed length to ~8.6". Since the 240z is ~100lbs lighter I'll see 1/2" or maybe 1" lift in the 240z application. MSA said the average spring rate is ~185 lb/in the 260z/280z operating range. I also have a pair of Autozone coils coming that fit the Front of a 280zx that are suppose to fit the perch of 240z/260z/280z: 11.4mm(3.94") Outer Diameter (12.1" free length, 0.515" wire dia., no spec on spring rate, I hope ~180 lb/in). This may get me close to the stock compressed height the 8.5" or maybe 1/2" higher. Then using the 260z/280z Stut Insulator in a 240z is my last resort to get me ~3/4" or so lift. Anyway .. any other advice is welcome...

Mezz is correct. MSA has New Strut insulators for both 240z and 260z/280z's. They are interchangeable between both models and they are a bit pricey so it's cheaper to lower or raise your car using different coil springs and shocks if possible. The 260z/280z Strut insulator is thicker making the car sit higher versus the 240z. I did order a set of 260z/280z strut insulators along with new 240z strut insulators so when I finally get around to replacing my rear shocks and coils - I'll be able to decide what parts to use so I get 1.75"-2' of more rear high. Anyway - MSA said the 260z/280z Strut Inuslator is 3/4" thicker than the 240z. I'll get an exact measurement when they all arrive and post it here. Also - Arizona-Z is out of Rear Stock height springs and no batch run in the future is planned so I'm in a real bind. Since most coil springs are now performance ones and lower the 240z ~1", the only option is for me to order a set for 260z/280z hoping the compressed length is close to a stock 240z spring. Anyway I ordered a set of Eibach's from MSA for a 260/280z 2+2; Free length is ~1" shorter than the stock 240z however the progressive spring rate on Eibachs is 80 - 300 lb/in with an average of 185lb/in (where as the stock 240z coil was 103 lb/in new). I'm hoping this gets me close or slightly higher than the stock 240z compressed height of 8.4". Anyway I'll let you know how it goes.

Esprist (or anyone who may know) .. I have a question. Q) What is the Height difference between a 260z/280z Strut Inuslator and the stock 240z strut for a rear suspension? I'm thinking of installing all stock 240z parts accept for the Strut Insulator where I'd use a 260z/280z one since I need a little more height given my wheels are 3/4" large in diameter (3/8" less clearance between Fender & Tire. I'm figuring to raise my rear suspension 1.75" to 2" with 1 adult in the car. My coils are stock original so I know I'm loosing almost 3/4" of height from them based on spring rate differences with the New Arizona Z Rear coils. Here's my assessment of height increase: => New Arizona Z Stock Height Coil: +3/4" increase (did the fronts and saw this height increase since rates of 100 lb/in Stock vs A-Z's 200 ft/in). => New Tokico Gas HP Shocks: ~1/8" at most. I'm removing 8year old HP Gas Tokicos and this is what I saw when I replaced my front ones. => New Urethane Spacer: ?? don't know here until I remove the current ones. At most +1/4" if they are worn, normal height is 3/4" for urethane new ones. => 260z/280z Strut Insulator: ???? MSA said 3/4" thcker than a 240z Strut Insulator. I ordered a set and will measure it exactly. ==> Total increase estimated using the 240z Strut insulator would be: ~1-1/8" at best assuming my urethane spacer is 1/4" thicker than the one I remove. ===> This still leaves me roughly 7/8" shorter than I'd like. That's why I'm thinking a 260z/280z Strut Insulator may get me the addtional 7/8"-1" in height I need. Many thanks for any insight and advice folks ...

Here's some settings I used on my car..... I have a 4BL Holley, 390cfm .. but setting the advance and Idle would be the same. When fully warmed up: 900 RPM normal idle - 16 BTDC advance 900 RPM car pulls 14-14.5psi vacumm. then set advance ... at 3k RPM. 3000 RPM - 42 BTDC total advance Note: when my alternator kicks on... my idle RPM drops around 50-80 RPM to 850-820 RPM. This is important... as I had to make my carb(s) slightly richer at low RPM so it maintained power. I had my carb(s) too lean.... Cold Idle Starting: 1500 RPM when started (choke pulled 1/2way) 2000-2100 RPM when choke fully pulled out. One final comment is you may have your Carbs set Too Lean. If your timing is set correctly, then try making your carbs slightly (1/8 to 1/4 turn richer). Readjust your idle and Advance to the above settings I reference and you may see improved power and acceleration under load. Here is one link for reference on idle mixture tweaking: http://www.classiczcars.com/forums/showthread.php?t=30161 Here is one that has a lot of information on ignition settings. Post #79 has my setup: http://www.classiczcars.com/forums/showthread.php?t=30380&page=4 Just my thoughts.... so keep us posted. Good luck.

Good luck ! Take your time and don't get frustrated. It's very challenging laying under the car driver front wheel area and reaching up with this L-shaped rod. You will need good lighting from under the car pointing toward the Hood Latch Release bracket area also. This will help with visibility such that you can line up the u-shaped hook easily in getting your Latch opened manually. Let us know how it goes !

In one of my earlier 73 240z's , the nylon speedo gear in the pinion had several teeth missing or chewed up. It must have been removed and replaced incorrectly at some point causing the gear to wear. While you have your Speedo cable out - remove the speedo pinion and check the teeth on the nylon gear. Nissan can order them they just need to know the # of teeth and gear color. Here is the link .. look at post #3. It has the Nissan PN's for the various speedo gears in the pinion - you can match your's up with. Looks like Courtesy Nissan also sells the pinion gears. http://www.classiczcars.com/forums/showthread.php?t=6997&highlight=speedometer+pinion One additonal point - I use 75W90 Valvoline in my tranny & rear end. When you change or drain your transmission oil, try to save it and measure how much you removed. Your oil may be low and thus the Speedo gear may not be getting lubricated properly, especially it's chewed up or damaged. I recented changed my tranny oil and it was actually overfilled by 12oz by the prior owner which caused it to leak out the rear at the shift selector, so make sure your car is level when refilling the tranny oil up to the fill hole. Good luck and keep us posted ...

I can't open the website url. Anyway from my experience shifting for me ussually occurs around 3k rpm. From 1st --> 2nd , I can do it around 2k starting off .. 2nd --> 3rd I try to keep it around 3k and the same for 4th & 5th. I have a 1982 5sp 280zx in my '73 240z. If I feel like having fun I'll shift around 4-4.5k for 3rd --> 4th and 4th --> 5th... the sound and pull is awesome. In general my best mileage and performance is when the car runs around 3k. I also have a vacumm gauge in place of the clock - so it gives me a good idea how my engine performance is doing all the time. Normal idle Vacumm is around 14psi, when driving steady state regardless of what gear I may be in I like to keep it above 10psi and if I remember correctly for my car - it's ussually when it runs above 2.0k rpm(maybe close to 2.3k). If I get below 2.0k and press on the accelerator - my engine power drops and it really lugs along. Not sure this is what you were looking for - but hope this helps.