chuckles Posted January 10, 2012 Share Posted January 10, 2012 (edited) Hi all, New here, been lurking for quite some time. Here is my story. Been a z-car nut since I was a teenager. 280zx was my first car. Now 36, I have had some sort of "Z" ever since. My current one is a 4/71 Series 2 240z. It's been in the "restoration" phase for say 14 years now..... Actually been in warehouse for almost 10 years in a 100 pcs. So far new interior, new paint, new suspension, new rubber, and cleaned and refinished almost every part on the car. Complete undercarriage detail, etc. Now this is not a 100 pt restoration. Just a clean, refreshed car. Here is my issue. In the time this was all being done, the poor L24 sat and languished in the weather for 8+ years.... So now it's a ball of rust.. Don't know specifics yet, but pretty sure the cylinders are rusted. Engine was sealed up, and up to about 6 months ago, all was fine, but the engine was moved, and one of seals was broken and moisture got and in did the rest. The SU's actually seem ok (need to be polished and rebuilt of course). Has E31 Head on it But.. I also have a 77 or 78 vintage 2.8 liter with N47(edit) head from a 2+2 complete with EFI manifold, injectors, sensors, etc. Does not have ECM or harness, fuel pump, tank, etc. I do have the matching 5 speed tranny, R200 rear end, half shafts, mustache bar, etc. Also have the 2+2 clutch and flywheel. I'm budget oriented on this build since i like to re-use as much as possible, and not have a bunch of leftover stuff. So with the parts on hand, what can be done? Keep this in mind. I am former BMW tech and ASE Master Tech, so I'm very familiar with all aspects of automotive systems, and EFI systems, etc, etc. But, I am not an engineer, or tuning expert, since I mainly worked on OEM auto with EFI, all that was left to the ECM. Basically all the build up of the engine I can do, as I have the space and the tools. I do not have a machine shop, so that part would have to outsourced. Also in Shreveport LA, so my choice of good, race oriented machine shops is limited. Dallas is closest big city. From my reading, I assume I can use the 2.8 block, bore it, source a LD28 crank, use the rods, intake, distributor (converted to pointless) and SU's from the 2.4, and make some sort of Stroker engine. I also assume I can mate this up the 4 speed for now with factory r180 rear end just to see how well it all works. Thoughts and suggestions are appreciated. Regards, Charles Edited January 14, 2012 by chuckles Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted January 10, 2012 Share Posted January 10, 2012 Yep, basically L28 block with LD28 crank, L24 rods and some KA24 pistons. The block will need to be bored and some say there is some clearance grinding on the crank. Here is a site full of combinations. http://www.zhome.com/ZCMnL/tech/128combo.html Quote Link to comment Share on other sites More sharing options...
chuckles Posted January 10, 2012 Author Share Posted January 10, 2012 Yep, basically L28 block with LD28 crank, L24 rods and some KA24 pistons. The block will need to be bored and some say there is some clearance grinding on the crank. Here is a site full of combinations. http://www.zhome.com/ZCMnL/tech/128combo.html Hmm, seems with the N42 head, you either have 11+ CR, or 9.5 and down, not much in the 10:1 range with N42 head. I need to go double check that head and make sure its N42. Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted January 10, 2012 Share Posted January 10, 2012 The L28's don't seem to like much above a 9.5 CR (or so I have read). You have to retard the timing massively and that offsets any additional power made by the increased CR... Quote Link to comment Share on other sites More sharing options...
chuckles Posted January 10, 2012 Author Share Posted January 10, 2012 The L28's don't seem to like much above a 9.5 CR (or so I have read). You have to retard the timing massively and that offsets any additional power made by the increased CR... With 9.5 CR, what kind of total timing are we talking about? 28, 35, 38? Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted January 10, 2012 Share Posted January 10, 2012 That, I don't remember.. I found the discussion here at hybridz, so it's in here somewhere. I think they had to take 10 degrees out but don't quote me. Quote Link to comment Share on other sites More sharing options...
t-tom Posted January 10, 2012 Share Posted January 10, 2012 The L28's don't seem to like much above a 9.5 CR (or so I have read). You have to retard the timing massively and that offsets any additional power made by the increased CR... You've read wrong. Go search Zredbaron On here and on youtube. That's a High CR stroker motor I think its in the 13:1 range. If you are going to turbo it then yes you would want lower cr but on a stroker the sky's the limit. Of course the sky is not cheep Quote Link to comment Share on other sites More sharing options...
rossman Posted January 10, 2012 Share Posted January 10, 2012 (edited) New here... I'm budget oriented on this build... ...make some sort of Stroker engine... Thoughts and suggestions are appreciated. You should be more specific about your budget and power goals. That will help us help you decide on a path for your build. A high powered stroker L6 isn't going to be budget friendly. You didn't mention EFI or Turbo so I assume that is out of the question. Edited January 10, 2012 by rossman Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted January 10, 2012 Share Posted January 10, 2012 You've read wrong. Go search Zredbaron On here and on youtube. That's a High CR stroker motor I think its in the 13:1 range. If you are going to turbo it then yes you would want lower cr but on a stroker the sky's the limit. Of course the sky is not cheep I agree that it is possible, but this post is about a "budget" motor. Zredbaron probably has upwards of $10k in his motor and runs 109 octane race fuel and has beautiful results. Without massive work to the head/valvetrain/piston shape/induction system or aftermarket efi, you probably won't have good results above 9.5 CR. That's my understanding and I could be wrong... Quote Link to comment Share on other sites More sharing options...
chuckles Posted January 10, 2012 Author Share Posted January 10, 2012 You should be more specific about your budget and power goals. That will help us help you decide on a path for your build. A high powered stroker L6 isn't going to be budget friendly. You didn't mention EFI or Turbo so I assume that is out of the question. Ok goals, 180+ RWHP More is better, but I'm attempting to be realistic here. Pump gas (93 Octane is fine) 3K on top of the existing parts I have since they are essentially free. I'm open to induction types. Turbo, EFI, or Carb is fine, I can work with any. Usually with Turbo, I assume it's best to start with Turbo longblock as the basis. Bang for buck is what I'm looking for. Thanks, Charles Quote Link to comment Share on other sites More sharing options...
ttodhunter Posted January 10, 2012 Share Posted January 10, 2012 Best bang for the buck is honestly to get a L28ET and drop it in. Add an exhaust and intercooler, bump up the boost a touch and 180rwhp should be easy. Quote Link to comment Share on other sites More sharing options...
Leon Posted January 10, 2012 Share Posted January 10, 2012 "Budget stroker" is an oxymoron. You can to 180whp with an L28 without much trouble, and it'll be even cheaper with an L28ET. As far as bang for the buck is concerned, the turbo swap is your answer. Heck, a stock L28ET will probably be about 180whp. Quote Link to comment Share on other sites More sharing options...
chuckles Posted January 10, 2012 Author Share Posted January 10, 2012 ok so what is more reasonable rwhp number?? 200, 220?? The turbo is an idea but does require more work in regards to wiring and sourcing a donor vehicle. Let's say I gave you the parts I have and 3K, what can I get for that? Quote Link to comment Share on other sites More sharing options...
ctc Posted January 11, 2012 Share Posted January 11, 2012 I would suggest start by reading the following thread 200+ WHP NA Build If it were me; Stock rebuild on the bottom end Megasquirt fuel injection Cylinder head porting and a rebuild Hotter cam Lots of guys on this site have done it. I might also suggest searching a little more as well. There are discussions of L28's with E31 heads, N42 combs, flat top vs dish pistons. It has all been gone over. FWIW, I went the stroker route and spent a ton of money and now am going turbo L28ET which I should have done from the start. For the cost of the stroker crank alone, you can pay for the Megasquirt. Remember with EFI you can always upgrade more later and add the turbo. It will always be cheaper to build what you have and enjoy it. Upgrade to more power later. Chris Quote Link to comment Share on other sites More sharing options...
Gollum Posted January 13, 2012 Share Posted January 13, 2012 I agree that it is possible, but this post is about a "budget" motor. Zredbaron probably has upwards of $10k in his motor and runs 109 octane race fuel and has beautiful results. Without massive work to the head/valvetrain/piston shape/induction system or aftermarket efi, you probably won't have good results above 9.5 CR. That's my understanding and I could be wrong... Yes you're wrong, but not in the way you might think. It doesn't take much to get a high compression L motor to run on pump gas in all honesty. And don't think of it as "you can't run as much timing because X person changed compression and it pinged at the same timing".... well duh! With higher compression you normally don't "need" as much timing. High compression also means smaller chamber, which means less distance for your flame front to travel, plus the more you compress a mixture the faster it will want to inherently burn. It WILL be more detonation prone, but that doesn't mean it will be inherently a bad setup. The biggest key to getting it to run well and be able to use pump gas is all in the cam. Certain aspects of head work can help, such as polishing the chamber to reduce head transfer to the head and such. For a 200hp goal, sub 11:1 compression won't kill you. Just get a good sized cam in there and dial in the timing, then just tune appropriately. Ok goals, 180+ RWHP More is better, but I'm attempting to be realistic here. Pump gas (93 Octane is fine) 3K on top of the existing parts I have since they are essentially free. I'm open to induction types. Turbo, EFI, or Carb is fine, I can work with any. Usually with Turbo, I assume it's best to start with Turbo longblock as the basis. Bang for buck is what I'm looking for. Thanks, Charles If you're only looking for 180whp you already have 90% of the parts you need if you're willing to get dirty. I know you have all that efi stuff there lying around, but remember that almost no matter what, since you want more than stock HP the ECU (or ECM, PCM or whatever you want to call it) will be fighting you the whole way. There's no point to go and waste money finding one and trying to make it work. So here's some basic plans I'd recommend considering: Plan 1: Estimated cost ~ $500-$750 Pull L28 apart and blueprint block. Have machine work done only if necessary. (generally it's better to re-use bearings and such if they're within spec, as aftermarket pieces aren't always what they crack up to be). Do basic headwork on the N42. Unshroud the valves, blend the bowl mildly, lift the upper wall of the intake port a bit, port match the intake manifold. Throw in a decent cam Install decent exhaust Rebuild SU's, tune them well There's no reason you couldn't get a solid 160whp on this build, and if you really pay attention to every detail 180whp is believable. Plan 1B: Estiamted cost ~ $1000-$1300 Same as above but bore over the pistons a good 3+mm (wall thickness won't matter a ton at these power levels imo). This will get you not only some extra CCs, but also bump the compression a bit. Both are wonderful things when utilized correctly. Plan 2: Estimated cost ~ $2500-$3000 LD28 Crank N42 Head KA24E pistons 2mm gasket Mild head work, same as above GOOD cam (isky or sunbelt grind) The problem with this option is that not many bother running SU's at this point with how much money you've spent, and you very easily get into the "while I'm at it" mindset, which WILL blow your budget. If you really do it all yourself you could come in way under the budget I just estimated. It takes lots of patience and endurance to find the parts and do the prep work yourself. The reward is that 200hp should be EASY. Shoot for 250whp and if you don't make it you don't make it. Focus your post build energy on plenty of dyno time and getting your carbs dialed in. Half the battle with any build is tuning it which is where a huge portion of the power really comes from. I can't count how many motors weren't making the expected power simply because of tune issues. With any above builds consider a good lightweight flywheel and solid clutch. Makes ALL the difference in the perceived power of the engine and will also free up a could HP. Plan 3: Estimated Cost ~ $1000 Find a L28ET donor or whole engine. Shouldn't cost more than $500 if you hunt long enough. Convert the car for EFI Wire engine Make exhaust Done The key to this is making sure you get ALL the parts from the EFI and such. People that piece meal together their turbo swaps have been much more likely to run into issues getting it running right. Estimated HP at STOCK levels should be at least 170whp. Turn up the boost with a $10 manual boost controller to 8-10psi and you should reach 200whp. Plan 3B: Estimated Cost ~ $2000 Same as above buy add: Larger, decent injectors. At least 400cc Megasquirt 2 LSX or similar coils Wideband O2 Intercooler You now have full timing control which will make a HUGE difference. You also now have a better cold running engine, and when tuned well will drive better around town. You'll get better MPG once tuned. You'll have quicker turbo spool, part throttle and throttle transitions will be much nicer. The big upside is that you can now bump the boost gradually as you tune it, all the way up to 15psi and beyond if you dare. You have all the parts in the mix to reach a solid 300whp. 400whp is doable but rare just because it comes dicey on stock pistons if your tune is rocky. Experienced builders tend to just put forged slugs in, and generally wouldn't have popped the motor anyways, while inexperienced builders tend to bite off more than they can chew and turn the boost up too high to early, and kaboom. 300whp is a very safe level though that thousands of people have reached with this combo. "Budget stroker" is an oxymoron. You can to 180whp with an L28 without much trouble, and it'll be even cheaper with an L28ET. As far as bang for the buck is concerned, the turbo swap is your answer. Heck, a stock L28ET will probably be about 180whp. I agree completely. But I also know that the L28ET is a totally different character of a powerplant than a NA L motor. It's as much a question of preference of the owner as it is cost for HP. I would suggest start by reading the following thread 200+ WHP NA Build If it were me; Stock rebuild on the bottom end Megasquirt fuel injection Cylinder head porting and a rebuild Hotter cam Lots of guys on this site have done it. I might also suggest searching a little more as well. There are discussions of L28's with E31 heads, N42 combs, flat top vs dish pistons. It has all been gone over. FWIW, I went the stroker route and spent a ton of money and now am going turbo L28ET which I should have done from the start. For the cost of the stroker crank alone, you can pay for the Megasquirt. Remember with EFI you can always upgrade more later and add the turbo. It will always be cheaper to build what you have and enjoy it. Upgrade to more power later. Chris Words of wisdom right there. I'm not sure that MS is really needed for a true budget build though. I think sticking with the carbs is a good idea if you're wanting to keep it simple and minimize the work required. Quote Link to comment Share on other sites More sharing options...
bradyzq Posted January 13, 2012 Share Posted January 13, 2012 (edited) I will add a Plan 1C (which was implied above): Estimated cost ~ $1000-$1500 Pull L28 apart and blueprint block. Have machine work done only if necessary. (generally it's better to re-use bearings and such if they're within spec, as aftermarket pieces aren't always what they crack up to be). Do basic headwork on the N42. Unshroud the valves, blend the bowl mildly, lift the upper wall of the intake port a bit, port match the intake manifold. Throw in a decent cam Install decent exhaust Purchase Megasquirt 2 Install and tune it The range is larger than in Plan 1 because you have options with MS2, such as getting rid of the distributor and running wasted spark ignition. The cost goes up a bit if you get the car pro tuned on a dyno vs. doing it yourself. Edited January 13, 2012 by bradyzq Quote Link to comment Share on other sites More sharing options...
EvilC Posted January 13, 2012 Share Posted January 13, 2012 Plan 3 and be done. Can be done for cheap if you find the right donor as stated. You will be happy with that swap esp if you are not chasing huge hp numbers. Quote Link to comment Share on other sites More sharing options...
Gollum Posted January 13, 2012 Share Posted January 13, 2012 Plan 3 and be done. Can be done for cheap if you find the right donor as stated. You will be happy with that swap esp if you are not chasing huge hp numbers. That's a good and a bad imo. HP is so easy to get it's infectious and you chase your tail like Big Phil. That dude has been around every mountain five times and still hasn't hit his power goals it seams. On the flip side a NA motor is a NA motor. You can only go so far until you hit extreme budget concerns so it's a good self-throttle on the project. I've only got 10k mi on my L28ET 280Z and I'm constantly refining the idea of what I'm going to do, and it WILL be something very unique, all because I'm not bitten by the turbo L bug. Quote Link to comment Share on other sites More sharing options...
(goldfish) Posted January 14, 2012 Share Posted January 14, 2012 You can do a budget stroker that works, Norm proved it. But I'm not saying it's easy. I think you would be farther ahead using the stock 2.8 bottom end and put all the money into head work and cam. Quote Link to comment Share on other sites More sharing options...
chuckles Posted January 14, 2012 Author Share Posted January 14, 2012 Forgive me for being new. Who is Norm? Also I found out today, that my 2.4 is a P30 block with E31 head... ?? 71 block with 70 head..hmmm My 2.8 is actually a N42 block with N47(emissions) head, so not sure now if it's worth messing with. I guess it would depend on how much work is needed to fix up a N47 head? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.