Jump to content
HybridZ

77 280z, Turbo the N/A motor with carbs?


l4ugh1ngm4n

Recommended Posts

So I've been working on my 1977 280z lately and I want to get some real power. I've been looking around at different swaps and upgrades and I have decided I want a turbo l28. I know there is a stock turbo l28 from the zx I could swap. But if I plan on building the motor internals, an N/A l28 would end up being the same thing after a rebuild for boost no? I would also love to do away with the fuel injection and run a carb setup. Is anyone here running a carbed and turbo l28?

 

Any help or input would be most appreciated. I'm sure this is one of those stupid questions that gets asked here on a regular basis. I apologize for being "that guy".

 

Thanks to everyone for your time.

Link to comment
Share on other sites

There are no stupid questions. If you try searching "turbo tom" That will give you some info on turbo/carb setups. Two different types of setups draw-through and blow-through. Each application is dictated by boost built before turbo or boost built after turbo and regardless of the setup, you won't ever be able to tune it as well as efi turbo setup, but it's definitely unique. You should read the turbo section and some of the stickies about boost and quench, it's some pretty deep stuff but I learned real quick there are some extremely knowledgable members on this forum both book and experience smart. You're definitely in the right place.

Link to comment
Share on other sites

I was once thinking of doing the same, my plan was to use a 4 barrel manifold with a 4 barrel holley (obviously) and a stock 280zx turbo manifold and turbo to do a carb'd blow-through setup. In my opinion this could be done for about $500 if you find some deals! One day if I've got the extra cash and time I still may try it. Sure it wouldn't have the power and tunability that an EFI turbo setup would have, buy it should make for some fun! Hope this helps at all.

 

Matt

Link to comment
Share on other sites

I run blowthru holley/t3-t4oe. Love it. Took lots of research and trial'n error. Cost about 2k. Most money had to go into fuel delivery. You need a boost refrenced fpr for a carbed setup. Aeromotive sells a nice piece for about 150$. theturboforums.com can answer any question ya wana know about carbed turbo.

Go to this post on hbz..thats my setup.

 

http://forums.hybridz.org/index.php?/topic/87310-blowthrough-280z-dyno-resultsand-pic/

Edited by 280zex
Link to comment
Share on other sites

I run blowthru holley/t3-t4oe. Love it. Took lots of research and trial'n error. Cost about 2k. Most money had to go into fuel delivery. You need a boost refrenced fpr for a carbed setup. Aeromotive sells a nice piece for about 150$. theturboforums.com can answer any question ya wana know about carbed turbo.

Go to this post on hbz..thats my setup.

 

http://forums.hybridz.org/index.php?/topic/87310-blowthrough-280z-dyno-resultsand-pic/

 

this is pretty interesting!! I need to keep in touch with you guys on this because I just converted my car to the Holley 390 setup and was wondering how the hell to turbo charge it. now i know but I will need some help from you guys.

Link to comment
Share on other sites

Here you have some pics ;)

 

DSC01239-1.jpg?t=1270579212

DSC01233.jpg?t=1270579377

 

I am turbo stupid and am going to need some help to do this to my Z. can you please post a list of all the weird small parts that I will need to complete a turbo install like this so that I don't have to kill myself having to try and research how to make this work.

 

Ronnie

Link to comment
Share on other sites

  • 1 month later...

I just made 279 rwh at only 5200 rpm limited due to operator (not me). Don't know why as the engines pulls hard to 7k. This was at the MSA show last month. The turbo system was an old Turbo Tom draw thru kit. It's very simple. The setup should really put down 300-350 with full pull and a little more tuning. I've enjoyed the build. Ive held on to this kit for over 20years and it was fun to finally get it going. I will be selling the whole kit for about 2k soon and going back to na as I just like the feel better. that will include modified gas tank, linkage, pump, polished turbo and intake, swaintech coated mani, hotside, 304 ss tubine discharge downpipe and wastegate. Polished methanol tank and new Holley carb. Even If you're not interested, don't let the efi guys bug you about carbs, they work too and if you aren't an electronics oriented guy, you won't get all this drivability advantage they're talking about or you will pay, pay, pay to have someone else do it for you! Enjoy btw, with out methanol or water and a little 390 4160, you can get 225 rwp on a stock 8.4 cr L28 at 8 psi

Link to comment
Share on other sites

Been there, done that, went EFI. EFI is not as hard a learning curve as you would think.

No moreso than Carbs. Anybody saying 'carbs are easy' needs to talk with someone who really set up one of these to get good drivability and not just WOT performance. Jetting, tip-in of secondaries, metering rods, pressure seals, gas leaks under boost.

 

It can be done, but when you realize the stock electronics can be replaced simply by a $400 box you buy off the internet and you basically have the ability to go from there to 350HP with little more than upgraded injectors, why re-engineer what is already working in the car?

 

Skip the internal rebuild, there are at least three people on this thread making 300+HP on stock N/A internals. One of them for over 20 years now (and that number is closer to 350 in his case.)

 

It's the EXTERNALS that will net you the power. THEN the head and cam. and if you decide you want to go over 400HP, THEN start thinking about internals. Up to that point, you're wasting your time and money on internal modifications.

 

If you don't have a turbo to support 350HP, you won't make it, period. If you don't have fuel to make 350HP, you won't make it, you'll BREAK it!

 

Regardless of the internals.

Link to comment
Share on other sites

Yup its them little parts that get ya. Turbo kits can be found for under 200.00. Mine was under 200 with shiping. EFI is way better to go with for daily driving. I would guess the first is start-ability I have NO choke. This makes the car cranky when its cold. Then its mpg or the lack there of. I dunno what mpg a 300+rwhp EFI turbo gets.I get 17 mpg cruzin and about 5 wot. Now its all about the odd-ball parts. I did more than a YEAR of research on already developed blowthru systems on american v8's. Then it came down to the "guess" work. That alone took 4 months. I went WAY overkill on my entire engine not taking into acount things like clutch/trans. Now it looks like I need to get a 240sx 5 speed and a new clutch disc and pressure plate. I decided to let the turbo go for glory and at 14psi the clutch gave out badly. I got home but the smell is NASTY and the interior smels like burnt eletrical/clutch. I just installed a fidanza flywheel and an ACT organic 6 puc 240mm disc and 400crank hp pressure plate.That lasted less than 1 month. Hopefuly the flywheel is ok. I dunno about hp but damn I hit 1.22g's (per the autometer DPIC g meter) from 2nd to third shift. Then slippage and the stink!!!!!!!!!! This tells me that my tire combo is up to the power- for now..

Link to comment
Share on other sites

Tony who do you speak of...lol I have more time and hair pulling in getting my carbs perfect........per the day. Meaning mine are changing daily if i get lucky i can drive a week without major changes. I have now put jets correctors and e tubes in my glove box for when i drive long distances.

 

Over the winter i will be going efi via my webers or mikuni's Is blow through fun sure sure. But when you drive for fun and drive daily for fun its a bear. I am also putting down way more HP than originally planned and am getting ready to loose a clutch due to the power. AS tony said to me. Ready to spend 1,400 on a clutch setup to hold it.

Link to comment
Share on other sites

My daily driver average was 17, with track usage around 5 mpg.

With EFI, daily driving was closer to 27, with track usage around 5 mpg.

 

Ben is already hitting on the technical items I got into with daily driving and 'livability'---the car runs great on carbs, and if you are in a temperate climate pretty darned well. But once you start instrumenting the thing and realize 'perfect' is not what you have and start going after it....then it becomes frustration X10!

 

Don't get me wrong. I would say 75% of the time in daily driving, the Carb Blow Through Turbo (Triple Mikuinis was my preferance over the draw throughs I had previously done) worked great. But when you realized the 25% of the time it didn't was irksome on a long trip, or on a cold morning, or on a HOT day you start working at it.

 

If I only drove the car on a weekend to a track event, or trailered it to a drag strip on the weekend, I would say it worked fine 99% of the time.

 

But the realization is (like when you start tuning EFI) is that 85% of your time is spent NOT on boost and many times it's in a vague area around "0" manifold vacuum with very small throttle openings getting the AFR to run well at 2500 and 35% throttle, and have the same drivability at 3500 at similar transitional throttle plate movements gets a bit maddening.

 

If the car is a weekend driver, blowthrough carb is quick and dirty and easily will net you HP if you have the turbo that will flow the air. You may never notice or get to the point of annoyance that daily driving at 60mph with a persistent 'cough' from the box when you are steady state going up a sliiiight grade on the way to work every day of the week. But do it every day, and you start to say "I got to fix this, it's bugging me for far too long"...

 

While MPG is nice, not having that niggling "cough" anywhere really is nice!

Link to comment
Share on other sites

Don't have any sneezing issues. I ended up with clutch and trans issues. So there goes 1.5k mabe less if I get lucky. At 1 point I almost went with TWM throttle bodies with SDS and turbo combo. I just couldn't shell out 4k. I haven't had to fiddle with the carb once I got it jetted right. I've been tuning in the winter so mabe this summer it'll have an atitude. I don't have an egt or iat guage either. I used a local shops thermal laser and checked the turbo housing while on the dyno. I saw 850f right on the housing. I still haven't had the $$ for ceramic coating the exhaust pieces due to the new clutch and flywheel. I think I hit the point where I should enjoy driving my Z and not the HP chase. I put the waiste gate back to 8psi. Gota drop the trans and check the flywheel and clutch disc. Then there is finishing off the bov/recirc valve. I have the exhaust end pointing at the induction side of the turbo I just never ran the short piece of hose. There is always something to do on the Z..

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
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...