skunk1551 Posted July 29, 2009 Author Share Posted July 29, 2009 I should have mentioned a higher octane but I am limited and those limitations present a huge gap from 91 to 111 to 114 octane with no additives to boost the octane. For now I am equipped with a 83 computer that was ordered out of california for a previous car, but I am looking into the megasquirt. Driving around on 111 would be ideal for me but it will be expensive. Quote Link to comment Share on other sites More sharing options...
Overkill Z Posted July 29, 2009 Share Posted July 29, 2009 everything you need is right here HAHAHHAHAHAHAH I NEED TO SAVE THAT LINK! As for the NOT having time thing...its always faster to do a search rather then asking for help and waiting for people to answer. Quote Link to comment Share on other sites More sharing options...
Guest Rolling Parts Posted July 29, 2009 Share Posted July 29, 2009 I run 91 octane in my mildly modded standard compression turbo L28. Anything below that is pointless if you want to actually use the turbo for BOOST. Hell, 91RON was the recommended fuel for the N/A engine! Adding both high compression AND boost will mean full time really expensive fuel. The 83 computer is not an "upgrade", it's still an old stupid fixed logic ECU. If you really intend to use it then you NEED the 82-83 turbo distributor (and oil shaft) so the ECU has some control over the spark advance. That's WHY I did not use that settup and went with a $400 MegaSquirt and a $100 EDIS. Basically MS/EDIS is cheaper than buying the 1983 ECU, 82-83 Dizzy, 83 harness, 83 AFM, etc, etc, AND the MS/EDIS is completely adjustable. Mind you it's also a hell of a lot of work to put together and figure out BUT don't think that the old 83 stuff is a cakewalk either. Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted July 30, 2009 Share Posted July 30, 2009 i would be saving some money on the bottom end(which are pretty tough and versatile as stock) and spending it on head work and standalone efi. As long as your block is nice and healthy just do a bit of cleaning down there, hone, new rings etc etc then take the money from boring out and spend it where it matters. Also, i'm in uni too... i don't have enough time either, in fact, what am i even doing here? Quote Link to comment Share on other sites More sharing options...
skunk1551 Posted July 30, 2009 Author Share Posted July 30, 2009 I would like to think my motor is in good enough shape. Im at 80k. For 1300 bucks I can get a complete block build kit without the crank, and I cant pass it up just to know when it is installed it will be new and strong. This kit also gives me wide range of cr to choose from. My intetion was to go 10:1 but since lower seems to be the way to go I will look into how low they offer. I am debating on a turbo still. I would really like the step or two down from the dico potato from jim wolf, hince the building of the strong block. That is still just an idea because those turbos are just unbelievable. I would like to run 10 to 14 psi constant but would like to handle 25 Since it looks like i am going to start with my original head, I want a different cam from schnieder to bump up the rpms from 6.5 to 8. This is just temporary till I can find a p90 Some parts I am looking at are here http://www.importperformanceparts.net/ Quote Link to comment Share on other sites More sharing options...
skunk1551 Posted July 30, 2009 Author Share Posted July 30, 2009 The 83 computer is not an "upgrade", it's still an old stupid fixed logic ECU. If you really intend to use it then you NEED the 82-83 turbo distributor (and oil shaft) so the ECU has some control over the spark advance. That's WHY I did not use that settup and went with a $400 MegaSquirt and a $100 EDIS. Basically MS/EDIS is cheaper than buying the 1983 ECU, 82-83 Dizzy, 83 harness, 83 AFM, etc, etc, AND the MS/EDIS is completely adjustable. Mind you it's also a hell of a lot of work to put together and figure out BUT don't think that the old 83 stuff is a cakewalk either. Normally I to would not have went with this I actually found it with the 83 harness,afm,computer. It is going to get changed for the megasquirt once I learn more. Looking into as we speak. Let me to Rephrase I ordered for my brother didnt pay for, but got the wrecked car back from a junkyard after his wreck. I wasnt sure what he did to it till after I pulled it out of the yard. Wasn't excpecting to see it again. I pulled my 77 out the same day I pulled his 76 Quote Link to comment Share on other sites More sharing options...
jc052685 Posted July 30, 2009 Share Posted July 30, 2009 I would like to think my motor is in good enough shape. Im at 80k. For 1300 bucks I can get a complete block build kit without the crank, and I cant pass it up just to know when it is installed it will be new and strong. This kit also gives me wide range of cr to choose from. My intetion was to go 10:1 but since lower seems to be the way to go I will look into how low they offer. I am debating on a turbo still. I would really like the step or two down from the dico potato from jim wolf, hince the building of the strong block. That is still just an idea because those turbos are just unbelievable. I would like to run 10 to 14 psi constant but would like to handle 25 Since it looks like i am going to start with my original head, I want a different cam from schnieder to bump up the rpms from 6.5 to 8. This is just temporary till I can find a p90 Some parts I am looking at are here http://www.importperformanceparts.net/ I would not be wasting any cash or time in rebuilding the bottom end. You will likely just trash it anyway in the tuning proccess. And if you think you are doing yourself a favor with a 10:1 compression on a turbo motor you have alot to learn. Quote Link to comment Share on other sites More sharing options...
kolonelklink87 Posted July 30, 2009 Share Posted July 30, 2009 I would like to think my motor is in good enough shape. Im at 80k. For 1300 bucks I can get a complete block build kit without the crank, and I cant pass it up just to know when it is installed it will be new and strong. This kit also gives me wide range of cr to choose from. My intetion was to go 10:1 but since lower seems to be the way to go I will look into how low they offer. I am debating on a turbo still. I would really like the step or two down from the dico potato from jim wolf, hince the building of the strong block. That is still just an idea because those turbos are just unbelievable. I would like to run 10 to 14 psi constant but would like to handle 25 Since it looks like i am going to start with my original head, I want a different cam from schnieder to bump up the rpms from 6.5 to 8. This is just temporary till I can find a p90 Some parts I am looking at are here http://www.importperformanceparts.net/ P90 would help higher comp. better but 10:1 is still very ambitious. as previously stated... to run that kind of comp wiht a turbo you'll most likely trash your bottom end if you arent EXTREMELY experienced in tuning $1300 will do a lot more for HP results in the top end than the bottom and these blocks are bullet-proof anyhow. Without the head work you are very limited in your overall HP goals and you will have to boost much higher than nessecary(or safe?) to overcome this. There is lots of info out there for headwork, some of it refers to NA engines but dont let that put you off... the concept of flow reigns true for turbo and NA. if finances are tight (beleive me i KNOW that one) I seriously think you should invest in the head, not the block. Also, you havent mentioned you original head (what is it?) if your HP goals arent absurd... i wouldnt be risking the higher comp etc etc. No need to reinvent the wheel there's plenty of info on here about acheiving up to 400hp without drastic or exotic modification. Quote Link to comment Share on other sites More sharing options...
JessZ Posted July 30, 2009 Share Posted July 30, 2009 WoW! Quote Link to comment Share on other sites More sharing options...
thrustnut Posted July 30, 2009 Share Posted July 30, 2009 Much better man, none of us here are trying to be mean, you just need to know what YOUR intentions are before you start your build, that makes it less abstract to help. I agree with the others, don't worry about the bottom end, no need to punch it out, forged pistons are a plus but with wanting 10 psi, I don't think the cost is gonna be worth it. As far as the head, there is so much stuff here about different combos its sick. I think an N42 or N47 (maby E88?) will get you up in the mid tens CR wise with flat tops where a P90 will put you low nines. From the reading I have done the P90 is the best flowing stock head which is why they used it on the turbo engines. If you want your RPM's up in the 8,000 range, I think flow would be a bigger consideration then CR (which you will be creating with a turbo anyway). Just make sure you have the turbo (and cam) to support what you want. It would suck to build it only to find out you start dropping boost at six, or your cam looses efficiency at 65000. It all has to match! I have a buddy building a MSS system for a turbo'd VW Bug, I think he spent 250.00 for the complete system. It looks like a bear (maby a little more time consuming then the search function) but do-able if you have a little electronics know how. Good luck, and save your money... do it right the first time! Quote Link to comment Share on other sites More sharing options...
skunk1551 Posted July 30, 2009 Author Share Posted July 30, 2009 I actually have two head a n42 and n47. the n47 need some work the cam chirps. Im driving the with n42 now out of a 76 280z. I also have a spare block. All the work is being done on a motor out of the 77 I pulled from the junkyard. I only drove that motor for 2 days before the head started to chirp. I was lucky to have another complete from a 76 so I just dropped it in to drive. Both motors are around 80k give or take 1k I was also looking at a whole motor out of a 83 just for the head and manifolds though, since the block is cracked. Might be a good later investment. UNKOWN right know of overall condition, I just know the block is cracked for sure. Quote Link to comment Share on other sites More sharing options...
PanzerAce Posted July 30, 2009 Share Posted July 30, 2009 10:1 is WAY high for any street driven turbo I would say. Look around, most of the guys building turbo engines stick with ~8.5:1, with some going down to 7.5:1 so that they can push serious boost and power on pump gas. And to give you some more idea of what 10:1 is like on L series: Most NA guys don't even go that high. Heck, my Rebello engine is only ~9.3:1 (still a screamer with the right timing advance ) Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted July 31, 2009 Administrators Share Posted July 31, 2009 10:1 is WAY high for any street driven turbo I would say... Especially for an L6 with no mods to improving coolant flow through the head! Stick with 7.5:-8:1 for boost, and conservative timing and boost until you get a good handle on things. More than a handful of guys on this forum with their first turbo L-6 builds have replaced head-gasket after head-gasket after head-gasket fighting the detonation demons... Quote Link to comment Share on other sites More sharing options...
jc052685 Posted July 31, 2009 Share Posted July 31, 2009 10:1 is WAY high for any street driven turbo I would say. Look around, most of the guys building turbo engines stick with ~8.5:1, with some going down to 7.5:1 so that they can push serious boost and power on pump gas. And to give you some more idea of what 10:1 is like on L series: Most NA guys don't even go that high. Heck, my Rebello engine is only ~9.3:1 (still a screamer with the right timing advance ) Agree!! Quote Link to comment Share on other sites More sharing options...
skunk1551 Posted July 31, 2009 Author Share Posted July 31, 2009 I must have read wrong MSA is the ones with flattops these other companies don't specify what the pistons are other than being forged. theser parts show me and tell me when I called that I have a choice in cr. One company importperfomanceparts.net say they are forged with a choice of cr being 8:5-1 or 9:1-1 the other racetep.com are labeled JE set for turbo with choice of bore, stroke, and cr. Now I know this motor of mine does have some wear and tear. I know I have raced it on the street for alittle over a year now and who nows what the other owner did with it. I want to say I might be better off rebuilding it just to be safe. A reason for wanting to rebuild is it wont only be a racer. I would like to make to some shows. I need as much as possible to nice and new to count for shows. I am kinda limiting myself to 2000 on the block and 2000 on head. That is what I am going to spend. So things still may change, but to let everyone know I will be spending a nice bit of change on both. I am a machinist which will help alot with machine work, which is why I am wasting the extra money where I would be spending elsewhere. Quote Link to comment Share on other sites More sharing options...
thrustnut Posted July 31, 2009 Share Posted July 31, 2009 Have you looked into stock 280ZX N/A flat tops? They are not forged, but for what your planing on running I would think they should be fine. If I where you I would spend more on the top end, thats where you will get the performance. The stock components on the bottom should be fine if your not planing on a full race engine. I was planing a turbo build, but decided to go carbureted due to lack of funds. I have the stock 77 block with 82 N/A flat tops and a P90 head (was to be used for turbo). I am running an Arizona Z 4 BBL intake and Edelbrock carb. My last mod was an MSA .460 270/280 cam, just waiting on installing the timing chain to start it up. I was worried about the CR being to low with the P90 and am still entertaining installing an N42 in the future, but I think even for my N/A engine with the 6500 RPM cam, maby flow is better then CR. I think my CR should still be around 9.1-1, so not a slouch by any means. Have you considered cryo-kits to help you up boost? Quote Link to comment Share on other sites More sharing options...
skunk1551 Posted July 31, 2009 Author Share Posted July 31, 2009 yes I was looking into cryo fuel rail and intake cooling along with my intercooler, but will not use the intercooler sprayer. Quote Link to comment Share on other sites More sharing options...
skunk1551 Posted August 2, 2009 Author Share Posted August 2, 2009 Now I thought with a lower cr it will be harder for the start and idle of the car and the drive ability will suffer a tad, being I am always around an elavation of 4500 to 5000. If this is the case I am gonna go with the 8:5-1 Quote Link to comment Share on other sites More sharing options...
thrustnut Posted August 2, 2009 Share Posted August 2, 2009 At that altitude you will loose power no matter what, but I would still try to stay around 8.5-1 just to be on the safe side and promote engine life for someone like yourself on there first build. I don't think you will have a problem with starting or idle, your biggest problem would be turbo lag until your engine becomes efficient. There are lots of stock cars out there with that CR they just don't have much power at altitude. Have you ever herd of turbo normalizing? Lots of aircraft use it not to produce more power, but to make sure that they can maintain rated HP up to say 25000 ft. That is something you will have to overcome anyway at 5000 ft, you will be normalizing for a while before you actually start making boost, that's why 1/4 mile ET's are slower where you are. I would keep it safe and pretty stock engine wise until you get a handle on things, then start bringing in the boost, intercoolers, cryo, CR...whatever. There's a video on youtube of a guy on his first drive in a SC Grand Prix GTP engine with LOTS of mods, but no tuning time. The first time he gets into it (on his way to the dyno) he blows it up....would suck to happen to you. Quote Link to comment Share on other sites More sharing options...
PanzerAce Posted August 3, 2009 Share Posted August 3, 2009 Now I thought with a lower cr it will be harder for the start and idle of the car and the drive ability will suffer a tad, being I am always around an elavation of 4500 to 5000. If this is the case I am gonna go with the 8:5-1 People's idea of driveability with regards to these cars is pretty flawed. I'm running a cam that most would consider undriveable for street use, but I DD that car for my job. The thing to remember is that these cars are LIGHT. There really isn't all that much mass to start moving. Quote Link to comment Share on other sites More sharing options...
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