Afshin

Dan, do you have any reference for the GM valve, such as part name, car model and year, part number...? Thanks

Originally posted by TonyD 15psi is about half of what Jeff is running. Even with good piston ring seals, there will be some blowby---the key is to minimize any oil migration whatsoever. I don’t believe that I was referring to Jeff’s car in any way whatsoever. I simply stated that with my set up, I have had no noteworthy problems to date, no more no less. I also have not implied that the stock set up could or should not be improved. I have thought about using a catch can myself, and certainly would modify it if I where to run 30psi. My point is that with 15-17 psi on a healthy stock engine (my car burns no oil) you can maintain a reliable and competitive car for non-professional level open road track events. I may very well modify my PCV system at some point, it’s just not on my priority list, but it is on my extensively never ending wish list (I have no significant oil build up in intake track, even after extended and hard use on the track…). As we all know, there is no end to reasonable enhancements that can be made to these cars, which is clearly demonstrable by my credit card bills However, I don’t see a healthy l28et having enough blowby at 15-17 psi level to cause detonation and damage the engine (many many of us have been running under 20 psi with stock pcv systems over many years). So my 2cents is that for non jeffP extreme set ups stock pcv will NOT cause engine failure…. Sure the system can be improved, but that is far from having to do it as the many other things one would have to do prior to having a reliable track worthy car. So the direct answer to the initial question is: No you will not experience the same problems as with the VG30DETT engine. BTW can you tell us a little more about your set up, 17 vs. 30psi goal, turbo, fuel system..…

I run the stock PCV system with 15 psi on open road tracks with no hint of a problem yet. I rebuilt my head 2 years ago so valve seals..are in good condidtion which probably helps.

Now that's FAST !!!!!! Congrats on reaching your goal.

Welcome to the forum Billy. You seem to bo on a good start. Which is good, since there is no end to these fun projects. It's sort of a drug and hangover free addiction

Yes, I believe that if you use one kit that they go on the outboard side. http://www.specprod.com/PROD_DIR/C_PROD_passcar_INSTALL_DYN.cfm?cmd=85720ins.txt&cmd2=85720 lLook at this picture and they brake cable line and confirm it's the same on your car. Also don't forget to consider sloting the other mounting points to give you better adjustability (you don't need to slot it that much).

VERY, VERY, VERY, nice!!!! I have been arguing for a long time that those engine are underappreciated. More importantly, when are you going to market the engine and tranny mounts? Hint hint

The car has more than enough and should do great on the track. I fully agree with fly327: Track time, track time, track time, track time, track time, track time... Then get even more track time and off course good tires, a tire pyrometer and good alignment shop all help. Oh, I almost forgot, keep saving money for more track time, as it almost always does more for your lap time than new hot parts (since you car is already well set up). Finally enjoy watching embarrassed guys with exotics cars look away from you in the paddocks (ego boost) and don't be embarrassed when someone with a beat up civic track whore gets ahead of you (humility).

I certainly don't know why you are getting a max duty cycle of 42%. However, that is not correct. 260-270cc injectors at 42% duty cycle with fuel pressure in 40 psi range will max out at about 130 HP. You can't get the HP without burning the fuel, there is simply no way around it. My guess is that for some reason you are getting 1/2 the actual number and that the scope is measuring 1 out of two cycles on the z set up, so that the actual max duty cycle is 84%. It just can't be 42% and have the car run at even 7 psi. Also under load, for sure, the car fires all injectors simultaneously and not in batches of 3.

look at that second turbo kicking in at 4000 rpm and giong up to 6800RPM. SWEEEET !!!! Next target 500 RWHP ?

Magic and 260ondubs Aussie octane rating is very different than the US rating. There are 3 octane ratings: RON (research octane number) which is used in Australia, Japan, is good at relating part throttle knock resistance. MON (motor octane rating), is good at relating full throttle knock resistance. Pump octane rating as used in the US which is RON+MON/2 captures both. Aussie 98 RON = US 94 pump octane 96 RON = 92 105 RON = 100 For turbo cars, MON is a better measure, since it relate to full throttle knock resistance. The US rating captures both RON and MON. However, manufacturers can make a gas with high RON and very low MON, which will pre detonate easily (so a poor 98 RON gas may actually have a pump octane of 90 instead of the expected 94). As such, the variability in gas quality for the same 98 RON is much higher than when using the other octane rating systems.

Congratulations !!!!! I can only imagine how hard it pulls with 1000lbs less weight than the supra. Waiting to see some numbers. I guess it's now time for you to wrinkle up strips of pavement

I'm not sure how many particles would escape the primary oilf filter (as long as it is a good one) for the second filter to catch it and prevent damage to the turbo bearings.... On the other hand, it is a smaller line and any thing that could potentally drop the oil pressure/flow, leaking fitting, junk getting in the line because of opening and closing it, ....would cause turbo failure. I don't have any real technical info on this, but my instinct would be to stay away from it as I see more room for problems than gains.

Definitely buy the book, it’s the best investment you could make!! It's filled with great useful info.

I have posted some updates on my suspension and results in this post. The car has come a long way since my previous write up in this old post. http://forums.hybridz.org/showthread.php?t=95061

That's great about the brakes Cody. I have been toying with the same idea. I have also considered getting the 11.4" 300zx rotors and then redrill them for a four bolt pattern and use a bracket along with the original 280zx caliper. The 84 rotor you got are then 10.4 or 11" (I thought they where 10.4). I'm, also considering a few other options, but need to get to a junkyard and check out some of the other car set ups first.... Can't wait to hear how your project turns out.

That's an old adjustable HKS pop off valve (I had bought one 13 years ago for my first 280Z turbo conversion). As you tighten the bolt, it compresses a spring which in turns increase the amount of pressure needed to open the valve.

you can also tighten the bolt on the pop off valve all the way down and it won't leak the boost anymore.

Hi Cody, The sway bar where the last addition to my suspension (I had poly bushings with rod ends prior to that). What prompted me to get them was the new found tendency for understeer after I got the back stabilized with the new bushings and alignment.... The gain was very noticeable. The car immediately felt better planted on the road, most notably in the twisties where the decrease lean was marked. It also made transitions from turn to turn a lot faster and stable. Benefits where even more pronounced on the track. It made it easier to modulate the car. In terms of deteriorating the ride quality, it only had a marginal effect. Of course with all the other mods and R compound tires, the ride is overly stiff in the pothole laden city, but more than fine everywhere else. My personal recommendation, is a strong YES in favor of the sway bars. You will feel the car being better planted on the road for everyday driving (even in relatively slow turns), the marked decrease in lean will keep the suspension geometry (which varies so much in our cars with compression/extension...) in line during hard driving (you will easily feel the difference) and again the was minimal change in ride quality (the R compound on the other hand had quite an effect on ride, but grip as well I can tell you with no exaggeration that the current set up handles amazingly well on the track and has shocked more people than you can imagine (myself included). It is light years ahead of where it was 2 years ago when I just had the eibach/tokico and 17" wheel combo. In short the adjustable and stiff bushings stabilized and planted the rear of the car and the sway bars balanced the handling to fairly neutral. BTW what is the rear brake modification you are working on? feel free to PM me

For my rear I have them set at -1 rear camber and 1/8 toe in as Jon had also suggested to me before. I have run numerous open track events since and have been tuning the suspension (I use a tire pyrometer on the track, which is of tremendous help). At least on my ZX, this works absolutely great for the rear. The car is amazingly stable and off throttle oversteer is mostly a memory (which I never imagined possible). I believe you will be most pleasantly surprised with the results. Of note, I used two kits, so all four control arm point are adjustable. Otherwise you may not get the exact camber and toe combination you want. If you have only one kit, you may want to slot the other mount (I would). Also, I should let you know that when I first used the kits, the bushings where occasionally binding, which resolved as they "settled in". ALso, they to tend to move out of alignment once in a while, so make sure the alignment shop marks the bushing alignment in reference to the mounting points with some paint, so every few months you can quickly check and make sure nothing has moved (I retorque them after getting it from the alignement shop). It's extremely easy to check and takes no more than 5-10 minutes (real time) to look at all four and re-align any that may have moved (I do this every few months and before track days). This has not been a serious problem at all, but you need to know this, and the gain, as I eluded to earlier the results are phenomenal. For the front, I have -1.2 camber, which works great on the twisties, street..., however, it is not enough for the track (rear has more traction than front with understeer hindering lap times...), so I increase the negative front camber on track days (slotted strut tower mount). BTW, when I had the front set at -1.7 at all times, I had excessive wear on the inner side of the tires. I hope this helps. (FYI, my set up consists of eibach/tokicos and suspension techniques sway bars with rod end links, all poly bushings, LSD..)

Hi Tim, I replaced the r200 with cv's from my 83 280zx turbo with a 1987 Z31 LSD. It was quite simple. All I had to do is swap the driveshaft flange (may need an imapact gun to do so for the freestanding R200 unit (loosen the one on your r180 before removing the cv's so you can prevent the driveshaaft flange from spinning under torque (using the hand brakes). Every thing else is bolt in (you also have to swap the differential mounts and use the original 280zx one, same bolt pattern for the mounts). The cv's are fully interchangeable (you may want to replace the seals with new ones while you have the unit out. Hope this helps. Have fun (it makes a huge difference).

Interesting article, however I think in light of all the R&D that goes into producing swirl and proper air flow in the design process of a head and all the various form and flows in different heads, such a one step design for all chambers may be risky. You figure it would have different effect at different speeds, volume, pressure, possibly affect airflow in undesirable way during intake or exhaust stroke.... Nevertheless, may be worth trying if someone has the extra time, head and is adventurous....I also think the edges of the grove would have to be somewhat rounded to minimize hot spots as already discussed. On the more practical aspect, I boosted my octane to about 93 and then was able to advance timing by 2 degrees and turned up the boost to 13-14 psi range with good success (or 16 psi on my second gauge, I rather go with the more conservative reading). This is a little better than the rule of thumb would predict for a 2 octane gain, but I think that 91 is just too low for high boost (and to believe that I figured that one out all by myself). Well at least I will be leaving CA this summer and will then have access to 93-94 octane at every pump So Cody, you prefer the plugs at .025 gap ? How is the idle, was it missing with larger gaps or did you just try 0.025 based on the amount of boost and stuck with it because it worked well....I run at .035 with a MSD box, I have not tried anything below .032 260ZRED, regarding lower compression from removing the carbon, I doubt that such a thin layer would have such a dramatic effect (though it may still play a role). Detonation because of heat retention seems to be a well described phenomenon, I just was not expecting so much improvement.

My battle, like most l28et owners has been mild detonation as evident by that damn pinging around 4200 RPM (peak torque). In my attempt to reduce it I have switched to NGK 8 heat range plug after having used the BPR7’s which are already one step cooler than the factory BPR 6. The 8’s did help a little but also idle is a tad rougher as well, but still fine. I then made my fuel mixture richer to 10.5-11:1 in the 3750 to 4500 RPM range, which helped but still had pinging on hard runs. Then as per Bernard’s suggestion, I enrichened the mixture earlier from 3500 rpm to allow for enough time to cool the plugs/chamber and it definitely helped, but I still was having occasional brief pinging at times. Of note, my timing was already retarded to 18 under full load (in the 3500-4500 rpm range). Now I being in California, I am subject to the worst quality 91 octane gas (high in MBTE..), but I felt that something else might be off. I remembered reading that carbon build up in the chamber will retain heat and cause detonation. So, I got a can of the famous Seafoam fuel treatment and used 1/3 of a can straight into my intake manifold (via a vacuum line), let it sit for 10 min, restarted the car, smoked like mad, got dirty looks from the neighbors and then went out for a spin. It actually got rid of the brief pinging under heavy sustained load, which allowed me to turn the boost up more, until I heard some pinging and then backed off the boost a little. So now I can safely run sustained 12-13 psi (peak 14-15psi) with junk gas. BTW I had used other good quality carbon cleaners via the gas tank with no noticeable improvement. I never would have thought that carbon build up would have this much effect on detonation!!!! I’m on my way to the NAPA parts store to buy another can of seafoam. Also, I did all this testing within 5 days, so there were no other variables (same temperature, same gas, same road). And no, I have no stock in Seafoam or NAPA

I agree with Clifton, I would not pick that one. This one is from the vendor that Z-Gad pointed out and certainly looks like it has a nice design, bar and plate, fins look good. See if you can get more info regarding psi drop,efficiency...from the vendor http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7954537024&ssPageName=STRK:MEWA:IT

Pin: 114 constant 12 V 27 & 35 ignition 12V 34 signal 12v , not part of 280zx harness 9 start signal 12v (powered when key in start position only) Check these, if you still think it's the ecu I have a working 84 turbo ecu (and MAF) that you can have for cheap. Just PM me if you want any of them.