AydinZ71

Here are the maps

1) I agree on the gearbox limitation! I’m looking into the new bellhousing conversion to use the 350z trans that Derek has prepared. Open to other suggestions! 2) thanks for the tip! I will message him. 3) according to Garrett, the GT25 550 is the most efficient turbo for my application, settling near 80% at full boost. Impressive! I would save quite a bit going to a GT3071. I am attaching the map overlays from Garett’s website for reference. Clearly I need to revisit my budget. What are all these turbo’s out there for $500? Are they all junk? 4) mishimoto seems to have a good following, but I have no first-hand experience. Even their largest universal unit seems to only be $275. No idea which IC manufacturers are better than others, but this is certainly a place worth investing. thanks again for your reply!

I can cover the motor build part. As mentioned, unless you “know a guy”, all the mods I am describing will disqualify you during your periodic smog inspection. for the motor build, you will need the following for sure: 1) larger injectors. 400cc is the lowest I believe you could go. 2) Intercoolers and associateD piping 3) independent EFI management 4) turbo with a T3 style turbine input flange. You will need to match your displacement and power goal to the right unit. GT30 would work. You will need an internal wastegate if using the stock exhaust manifold and downpipe 5) not sure how well the P79 head will flow. Almost everyone running turbo’s I come across are using a P90 or P90a head. Do some more research On this. 6) BOV 7) the block internals will work just fine for 300ft-lbs torque, except the NA pistons are a bit sketchy. Better off using forged pistons intended for a turbo car. The stock turbo pistons have the rings recessed lower on the piston to avoid the heat from combustion. NA pistons will probably work, but the rings may wear sooner. 8. ) need to adapt your oil pressure sender fitting And add an oil line to the new turbo 9) upgraded fuel pump like a way to 255 you need to tune BEFORE running more than 8psi. You will destroy your pistons in no-time if you attempt high boost and happen to have auto-detonation (pinging), usually caused by fuel starvation or a poor tune.

Could be for sure! It is flow-limited based on the linear(ish) torque drop-off. If you are confident the intake manifold is the largest factor, Protunerz out of Ottawa makes a custom intake manifold with larger TB. I purchased as a bundle with turbo exhaust manifold and downpipe. Looking forward to seeing the build quality when he is finished sometime in Feb. Let me know if you want me to make some measurements when I receive mine.

look at that torque drop off! You got room to run! If you can improve the head flowrate, You can bump up your HP quite a bit, even if you didn’t add a single peak ft-lb of torque.

Hi all! this post is about my L28et powered 71’. Some quick specs to start below. I purchased her stock in 2002 when I was 16, and had her mostly done by 18. I sold her to a great guy un michigan 5 years ago when I moved to Florida for a job. Since then, I was divorced and returned to California with my kids and struck a deal with the new owner recently to buy her back. I’m preparing for her return this Spring, and have already started some part purchases since. how she sits today: - L28et with JE forged pistons, overboard 1mm - stock P90a head with hydraulic lifters -stock manifolds and downpipe - SDS EFI & 450cc 75’ MB Bosch injectors - T3/T4 super 60 trim turbo - single Supra IV core IC & 2.5” steel plumbing - HKS racing 1” bore BOV - 280zx NA 5-speed - R200 3.7 open diff from a Z31 parts I have purchased for her return: - Protuners custom intake manifold, TB, exhaust manifold and downpipe. - Wlad’s super 8.8 rear-end kit and CV’s - 15’ mustang GT 3.31 LSD diff. - going to be using a P90a head with solid lifters off the SCCA race car. Will have it ported, polished, valves deshrowded, and still looking for a turbo cam to extend my peak torque to a higher RPM. As most turbo L28’s, she starts dropping off early at 4500-5000rpm im delving back into turbo and IC purchases and noticed a lot has changed! For my torque goal of 400ft-lbs, I ran Garett’s turbo calculator online and it seems the most efficient and appropriate turbo for my application is a GT25 550. yeah... that’s where I started LOL. That’s how little I know about the current market. It also seems insanely expensive at $2,000! Spearco was also the leading manufacturer of IC’s at the time, but no idea who makes quality cores now. id love to hear your choice of a turbo and IC for a budget of $1,000 or less for the turbo and $750 for the assembled IC core. I can manage the plumbing. If you feel that budget is too small, I respect that and would love to understand why something more expensive is worthwhile! IMG_5039.MOV

Sorry all for the repeat posts! Looks like I made the mistake of including punctuation (incorrectly) in the subject line. Post is below once I confirm I did this right

Spot on! Also poor spelling on my part. Thanks all!

Hello admins! I have tried a handful of times to post something, but there seems to be an error when clicking on the post. Sorry about the duplicates! You can tell there are several in a row. May you please delete them? I can try again, unless you are aware of what the problem may be 🤷🏽‍♂️

TESTING... I tried three times but my posts all had errors and would not open 😕 giving this a try.

I used the original mapping from a friend who had a similar setup. I eventually went to a tuner dyno by John Wayne airport, but they have long since gone out of business. I will need to find a new one myself eventually. If you do go Independent EFI, You could try contacting the manufacturer for a local shop recommendation. SDS was able to provide some names way back when I was looking for a shop. You want to find a shop that has experience with your specific EFI cobtroller.

Hi all! this post is about my L28et powered 71’. Some quick specs to start below. I purchased her stock in 2002 when I was 16, and had her mostly done by 18. I sold her to a great guy un michigan 5 years ago when I moved to Florida for a job. Since then, I was divorced and returned to California with my kids and struck a deal with the new owner recently to buy her back. I’m preparing for her return this Spring, and have already started some part purchases since. how she sits today: - L28et with JE forged pistons, overboard 1mm - stock P90a head with hydraulic lifters -stock manifolds and downpipe - SDS EFI & 450cc 75’ MB Bosch injectors - T3/T4 super 60 trim turbo - single Supra IV core IC & 2.5” steel plumbing - HKS racing 1” bore BOV - 280zx NA 5-speed - R200 3.7 open diff from a Z31 parts I have purchased for her return: - Protuners custom intake manifold, TB, exhaust manifold and downpipe. - Wlad’s super 8.8 rear-end kit and CV’s - 15’ mustang GT 3.31 LSD diff. - going to be using a P90a head with solid lifters off the SCCA race car. Will have it ported, polished, valves deshrowded, and still looking for a turbo cam to extend my peak torque to a higher RPM. As most turbo L28’s, she starts dropping off early at 4500-5000rpm im delving back into turbo and IC purchases and noticed a lot has changed! For my torque goal of 400ft-lbs, I ran Garett’s turbo calculator online and it seems the most efficient and appropriate turbo for my application is a GT25 550. yeah... that’s where I started LOL. That’s how little I know about the current market. It also seems insanely expensive at $2,000! Spearco was also the leading manufacturer of IC’s at the time, but no idea who makes quality cores now. id love to hear your choice of a turbo and IC for a budget of $1,000 or less for the turbo and $750 for the assembled IC core. I can manage the plumbing. If you feel that budget is too small, I respect that and would love to understand why something more expensive is worthwhile!

Hi all! this post is about my L28et powered 71’. Some quick specs to start below. I purchased her stock in 2002 when I was 16, and had her mostly done by 18. I sold her to a great guy un michigan 5 years ago when I moved to Florida for a job. Since then, I was divorced and returned to California with my kids and struck a deal with the new owner recently to buy her back. I’m preparing for her return this Spring, and have already started some part purchases since. how she sits today: - L28et with JE forged pistons, overboard 1mm - stock P90a head with hydraulic lifters -stock manifolds and downpipe - SDS EFI & 450cc 75’ MB Bosch injectors - T3/T4 super 60 trim turbo - single Supra IV core IC & 2.5” steel plumbing - HKS racing 1” bore BOV - 280zx NA 5-speed - R200 3.7 open diff from a Z31 parts I have purchased for her return: - Protuners custom intake manifold, TB, exhaust manifold and downpipe. - Wlad’s super 8.8 rear-end kit and CV’s - 15’ mustang GT 3.31 LSD diff. - going to be using a P90a head with solid lifters off the SCCA race car. Will have it ported, polished, valves deshrowded, and still looking for a turbo cam to extend my peak torque to a higher RPM. As most turbo L28’s, she starts dropping off early at 4500-5000rpm im delving back into turbo and IC purchases and noticed a lot has changed! For my torque goal of 400ft-lbs, I ran Garett’s turbo calculator online and it seems the most efficient and appropriate turbo for my application is a GT25 550. yeah... that’s where I started LOL. That’s how little I know about the current market. It also seems insanely expensive at $2,000! Spearco was also the leading manufacturer of IC’s at the time, but no idea who makes quality cores now. id love to hear your choice of a turbo and IC for a budget of $1,000 or less for the turbo and $750 for the assembled IC core. I can manage the plumbing. If you feel that budget is too small, I respect that and would love to understand why something more expensive is worthwhile!

Hi all! this post is about my L28et powered 71’. Some quick specs to start below. I purchased her stock in 2002 when I was 16, and had her mostly done by 18. I sold her to a great guy un michigan 5 years ago when I moved to Florida for a job. Since then, I was divorced and returned to California with my kids and struck a deal with the new owner recently to buy her back. I’m preparing for her return this Spring, and have already started some part purchases since. how she sits today: - L28et with JE forged pistons, overboard 1mm - stock P90a head with hydraulic lifters -stock manifolds and downpipe - SDS EFI & 450cc 75’ MB Bosch injectors - T3/T4 super 60 trim turbo - single Supra IV core IC & 2.5” steel plumbing - HKS racing 1” bore BOV - 280zx NA 5-speed - R200 3.7 open diff from a Z31 parts I have purchased for her return: - Protuners custom intake manifold, TB, exhaust manifold and downpipe. - Wlad’s super 8.8 rear-end kit and CV’s - 15’ mustang GT 3.31 LSD diff. - going to be using a P90a head with solid lifters off the SCCA race car. Will have it ported, polished, valves deshrowded, and still looking for a turbo cam to extend my peak torque to a higher RPM. As most turbo L28’s, she starts dropping off early at 4500-5000rpm im delving back into turbo and IC purchases and noticed a lot has changed! For my torque goal of 400ft-lbs, I ran Garett’s turbo calculator online and it seems the most efficient and appropriate turbo for my application is a GT25 550. yeah... that’s where I started LOL. That’s how little I know about the current market. It also seems insanely expensive at $2,000! Spearco was also the leading manufacturer of IC’s at the time, but no idea who makes quality cores now. id love to hear your choice of a turbo and IC for a budget of $1,000 or less for the turbo and $750 for the assembled IC core. I can manage the plumbing. If you feel that budget is too small, I respect that and would love to understand why something more expensive is worthwhile! IMG_5039.MOV

Hey there Derek! I have scrolled through the post and saw your pricing, but I think I missed when you will have this available for sale? How are you transacting sales, through a website or PayPal? I’m definitely interested! My NA 5-speed will not last much longer on the L28et.

If you are looking for a 300hp daily driver, you need the L28et pistons or custom/forged. The ring/piston design can be reliable for thousands of miles on a good tune. Stock L24/28 pistons will not last. At best your ring life is greatly reduced. Keep an eye on your CR as well. There is plenty of information on here about what head/block combos will yield. You should not exceed 8.3, but ideally you should be below 8. if you want to stick with NA pistons, run a much less ambitious boost (8 psi) with a good IC to bring down your induction temperature. I still think you will be unhappy with the ring life but if you plan to pull the block eventually, you don’t have much to lose. As far as the head, I second getting a P90. I don’t have any experience running any other head on a turbo application. I will have a P90a with hydraulic lifters for sale in about 3-4 months once my P90a with solid lifters gets rebuilt.

have you pulled the stock L28et pistons yet? Curious to hear your impressions. I don’t have a recommendation on a specific ring material. Are you considering forged pistons? Since piston ring performance on a turbo engine is not specific to Nissan/Lseries, you could ask some of the experienced aftermarket piston suppliers like JE and see what they think. I believe the degree to which you experience pre-detonation (knocking) is the main culprit in short piston/ring life on an L28et. The higher the boost, the more ring wear you will experience but it should not be drastic unless you are knocking

Got a vid of the 71’ L28et from Michigan. Thought I’d share IMG_5014.MOV

I also recommend the wideband A/F meter as well! would have made troubleshooting and tuning SOOO much easier, and from what I see they are only $200-$300 including the O2 meter and gauge. Off-boost, you will be looking for ~14, while 13-11.5 is typical while boosting (depending on pressure and your detonation risk).

In 2001, I tried to run a swapped L28et harness on an L24 I was adding a turbo to. weeks later, I gave up after having no success and went with SDS ignition and fuel management. I was really glad I did! I took the tune map from a friend of mine with the same setup, and it worked just fine. I simply reduced the fuel/RPM proportionally to run the L24. I blew that motor, but it was entirely my fault for running 8psi on a near 9:1 CR (I was 16 and ambitious). Eventually I bought a stock L28et long block and just swapped the SDS part to that motor. I ran that way for two years before I ever got to a dyno. I never had any detonation problems, never blew a head gasket or any mechanical engine issues. When it was finally dynoed, it did ~325ft-lbs at 16psi, and just around 300hp. Installation of the SDS system was super easy too. I just followed the directions and had to fabricate some simple brackets using AL plate and a hand drill. The hardest part was drilling holes in the front crank pulley for the crank position magnets. This is the only part of the installation that took any precision. I used the existing distributor to get the spark to the right cylinder, but SDS managed the ignition timing. I don't have any experience with Megasquirt (it was a less viable option 20 years ago, as I don't believe they had an affordable muiti-port option). Id love to hear from others in the community on how easy it was to tune their megasquirt systems. Once you go AM ECU, there is nothing inherent to the electronics that would limit you. You can run stock boost or add all the necessary parts to go much higher. Even at stock boost, I would add an IC immediately. Your first limit will be the stock injectors, followed by the stock T3 turbo, and so on... My recommendation would be to stick to around 300ft-lbs of torque. Once you get near 20psi, the occurrence of blown head gaskets start popping up (even without detonation). The mechanical torque limit (reliably) on a stock L28et is around 350-400lbs anyways, so why bother. Above that, you will need forged pistons etc. etc...

Wet blanket 😕 ... I don’t recommend it. Based on many posts from the early 2000’s, most folks got frustrated and went with FI ultimately. Getting A/F ratio right on a turbo setup is by far the most important aspect of tuning Due to the risk of detonation. SU’s are a constant-velocity carb that forces intake restriction to achieve this goal. Those that were marginally successful swapped out to a supercharger-ready down-draft carb but were still plagued with tuning issues. this was popular way back in the 70’s-80’s before tunable FI systems became ubiquitous.

thanks for the photo!! So if I understand correctly, at least one of these holes should have some ducting to ram air from the underbody. Is there a concern about dirt/debris getting into the drum assembly while driving? I’m just concerned there isn’t a way for it to get out once it’s in there. Maybe it’s not a big concern during a single session, but something to consider long-term. Maybe il design something to Temporarily close the holes when not utilized.

thanks! That is helpful feedback yeah I think I’m going to try The performance shoes recommended by others on this thread, and keep the drums for now.

thanks!! Looking forward to the picture

All done! Waiting in the GC camber plates, and this will be re-assembled