The Microtech LT16 will be available in the next few weeks. It has all the functions a 4rotor requires and is designed with n/a engines in mind e.g 32x32 instead of 16x16 and user definable load points.



The owner of the red FD is currently working on a sideport 4 rotor using tallport center plates. He's using a robot arm and flow bench to get all ports flowing the same amount.

Does it make a difference how the air flows, or is it just the volume that matters?

Well, both. You want the same port timing on each rotor. After you use a template for modifying port timing, you would want to flow test it to make sure each port is just as efficient as the others as far as volume goes.

I still have not heard back from my original email to Jeff (precision) which makes me wonder whether or not he thinks I'm serious or not. So I guess I will just have to email him till he gives me the time of day, or tells me to **** off https://www.nopistons.com/forums/pub...#>/biggrin.png

Sad when you have to pester someone to take your money.

Damn Skippy. I also dint think that I was as ready as I thought...still lots of things to consider about the project, just dont know whether or not it has anything to do with the parts that I need to get from Jeff. For example, I thought about the OPM and if it still needs to be used, or does it depend on the ioling system, or do I just want to run premix? Sometimes I wish there was just a cheat-sheet...

he have an email address?

I need your opinions on using a GSL-SE intermediate plate in the centor of a 4 rotor 12A. It's the only one with threaded holes at the bottom of each side for motor mounts, and is compatible with earlier rotor housings. I figured the engine's extra 128lbs of weight would be ok if centered over the motor mounts instead of hanging from the front cover and bellhousing. Thoughts?

Or what if I used two GSL-SE intermediate plates; each one with a stationary gear/bearing, with motor mounts spanning one to the other? I'd think the engine would be better supported. A regular 12A plate would be in the middle.

I think that would held disperse the load from the engine to the mount. Do you plan on shifting the engine back at all?

Maybe only an inch. We still want access to the oil filter and don't want to have to dimple much for the slave cylinder and clutch fork. It's going into a GSL-SE.



I'm thinking fairly conservative peripheral ports and stock apex seals should keep the HP peak before 8k-8400 so we don't over rev it and blow them. We'd also like it to be fun to drive/streetable. He already has a couple race cars.



Heh, a GSL-SE is getting 12A rotors. https://www.nopistons.com/forums/pub...1047683664.gif



Well, 4 of them. https://www.nopistons.com/forums/pub...IR#>/bigok.gif

Schweed! I want to see this thing. Where've you been Jeff I havent seen you since the BBQ last year.

Why are basing the engine on a 12A? Is it just to keep it as short as possible?

Yes and because he has several '83-'85 12A cores to go through. The total length will be 630mm or about 25" from the rear plate to the front cover. It will interfere with the front sway bar so we've got to move the tranny back a little. We'll also rotate the crossmember so we'll have enough room for an oil pan. The dual GSL-SE intermediate plates should solve any motor mount strength issues we would have had with only one intermediate.



Thanks to Banzai, it looks like I can get away with an FC front plate to take advantage of the larger turbo oil pump, which Jeff Bruce says will be enough for a street driven car. The next step is finding someone to do the p-ports in some rotor housings.



A GSL-SE front cover with OMP will allow for four oil lines; one to each rotor housing or carb in a dual IDA setup, depending on whether we need to get four new rotor housings, and if they have holes for oil injectors, and if not, directly plumbed to the carbs or manifolds should work.



Would a fuel cell and larger lines be a good idea for the kind of output this thing should produce?

Depends on what size the existing line is and what hp you want to be able to support. I dont see any real reason to make a new cell, assuming you can fit the pump in the stock unit.

Stock line size is 5/16, HP expected is 400. If I recall correctly, the SE had an external pump. It would be no problem to plumb in a high volume low pressure pump in the stock location. I was thinking at least the line size should be increased to 3/8" or so, especially at such a low fuel pressure.



The owner of the car wants to do a widebody and suspension upgrades, so I don't suppose he is beyond a fuel cell at this point. I'll run it by him.

Most of the aftermarket 400+ pumps run a 3/8 line. The pump should be mounted in the tank to help keep it cool. Is there an access panel in the stock cell?

There is a round hole at the top of a fuel cell, but it's for filling. The stock tanks of 1st gens just have lines and external pumps. I'm almost 100% sure the GSL-SE has an external pump. I think a large Carter or similar carb pump would work ok, but it would be a good idea to have a 3/8" feed line, and it might be more cost effective to replace the stock tank with an aftermarket fuel cell rather than figuring out a bigger sumped suction tube in the stock tank.

The GSL-SE's do have an external fuel pump.



That SE sounds like my old GSL-SE.....except I only had 1 12A in it LOL

Jeff,



The SE does have an external pump. However as you already know it will not flow enough. If I was more familiar I would be more than happy helping you choose a FP but I am only familiar with FI setups. lol The tank is baffled so there is no worries there. Also the pick up tube is huge. Right under .5" in diameter. The lines are also fairly decent sized but I can't remember the size atm. IIRC(and don't quote me on this) they are around 6AN.



I am running a REW in my car with a large single. Here is my fuel setup from the tank to the rails:



Stock SE tank

100 micron filter

Aeromotive a1000

6AN SS Braided line

Fuel filter



For the return I used the stock feed line.



I would love to check out the project some time. I have always wanted to put a 4-rotor in a SA/FB.



I also saw someone that put a cosmo engine in a FB. Since the motor mounts are located to the rear they made mounts that extended to the front. I would not advise this since the distance is quite large.



Are you going to be running this like a true 4-rotor? Or just 2 mated 12a's?



Z

The lines on a GSL-SE are 8mm or 5/16". Even the JC Cosmo with the 20B uses the same size lines. Of course being fuel injected and at around 43psi helps.



Since we're planning on running two weber 2bbl carbs, we're going to need at least 3/8" or possibly 1/2" line to supply enough at the lower pressure a carb typically sees. I'd imagine the tank's supply line to the pump is only 5/16", so this may present a problem if we decide to keep the tank. I'd feel a lot more comfortable if we just went with a fuel cell instead, and use at least -8AN throughout.



My 20B had a decent setup.



16 gallon fuel cell

-8AN fittings

3/8" prepump filter

255lph Walbro pump

3/8" brake line as send line

100 micron EFI filter



The return line used the car's stock send/return lines Teed together with the breather line (all 1/4")



The injector rails would pressurise very quickly. https://www.nopistons.com/forums/pub...IR#>/smile.png



I wonder why the person with the Cosmo engine didn't simply swap front covers. I'd imagine only a GSL-SE pan would fit a 13B correctly in a 1st gen engine bay. Then again, the FD engine that used to occupy this GSL-SE had some U channel stock fitted around the steering centerlink to use the stock FD mounts in the FD position, and the FD pan seemed to fit fine, I think. The motor mounts on the main crossmember were cut off to accomplish this. I was thinking since they were already cut off, it wouldn't be too difficult to fab something new to mount the 4 rotor in there after the U-channel is removed.



It will definitely run like a true 4 rotor with one rotor face firing every 90°. Honestly, if there were no shafts available for the 90° firing order, I would not be interested in this project.

That setup you had sounds pretty solid. And that is pretty neat with the teed line.



On mounting the cosmo engine my thoughts exactly. Seems like a lot more work. But I guess that it is a viable option of you do not want to rip into the engine. When you get that thing mounted in there make sure to take pictures. If you did pick up a 4-rotor e-shaft then I am sure that you could still probably use the SE mounts and just "re-adjust" the firewall. Then take a little more off the TII tranny to make it bolt in the correct location. A N/A 4-rotor would provide power and reliability. Can't really beat that. What are you expecting from the engine?



Where are you planning to get the E-shaft. IIRC there are only a couple people that make them. Kiwi and another one that is escaping me right now. Also I am interested in the cost of one of these units. I know that the 4-rotor kit from Kiwi is in the tune of 9k or something like that. Kinda spendy IMO.



I agree I have heard that the "true" 4-rotor sounds better. But honestly I have never heard a 4-rotor in person.



What kind of ignition system are you planning on using?

just had to link this.. =) http://www.youtube.com/watch?v=bHqAi...&search=rotary

I think he was going to use the GSL-SE tranny at first. Then switch to a T2 when it breaks. Kind of a waste of a GSL-SE tranny. Maybe I can convince him to go T2 from the beginning.



We were expecting about 100HP from each rotor. Does that sound right for a 12A sized rotor and a modest P-port? There is no need to go as large as MFR sized ports on this engine. Just a modestly sized set of ports that peak lower than 8k because this will be used on the street. Heck, I'd settle for peaking at 6k like some stock ports.



Jeff Bruce. We'll just be getting the basics from him to keep the costs down. We already have the rest of the parts sitting here or within easy reach. No need for an expensive kit. https://www.nopistons.com/forums/pub...IR#>/smile.png



The exhaust I'm planning to build should allow the nice 4 rotor sound to come through. My 20B sounded pretty sweet. This will be louder of course (peripheral ports don't like to be muffled very much). https://www.nopistons.com/forums/pub...#>/biggrin.png



Since we'll be using carbs, a modded dizzy system will be used. If we ever go ITBs, then I'll let the ECU handle the ignition. Each leading plug will get a spark every 180° like a 2 rotor with a direct fire ignition comonly known as 'wasted spark' or simultaneously fired. It'll be a lot easier to set up than the 20B was.

How long ago did you place your order?

Jeff, Thanks for the information. I would really like to learn from this build. I was wondering if you would document the entire build, especially the engine build? Pictures are optimal. https://www.nopistons.com/forums/pub...IR#>/smile.png



As far as the tranny goes I just would fork over the 250 for a good tranny from the get go. It saves a lot of headaches down the road. Your total cost to put a T2 tranny would be about 550 if you got a custom driveshaft. 250 for a good T2 tranny and 300 for a custom shaft. When a budget is in mind though this can quickly be altered.



If you are planning on 400rwhp then the rear end might want to be changed out. People *say* that when you are at 350-400rw you are on the bubble. It really depends what you are doing with the car. I personally plan to beat the hell out of mine and see what she can do. So many people change them out for the heavy, clunky 8.8" ford units. Sure they can hold the hp but they also rob it from you... I have heard that additional bracing helps as well. I can discuss this more indepth at the annual BBQ if you plan on making it.



What is included in the "basics"? https://www.nopistons.com/forums/pub...IR#>/smile.png



You are planning 4 ignitors then for the ignition? With direct fire of course! https://www.nopistons.com/forums/pub...IR#>/smile.png





Anyway thanks for the information thus far. If you can't tell I am really interested in this project!



Z

Danomite, we haven't placed the order yet. My friend is over in Korea at the moment. We'll discuss it when he gets back.



Z, I thought I recognised your user name from somewhere. Are you a mod in the NW section of the club forum or something?



I'm kinda busy but occasionally find the time to write threads here and there. If I do document this project on a forum, I'd probably do it here in the 1st gen section. I documented my 20B conversion in the 20B forum. Hmm, maybe I ought to document the 4 rotor project in this forum instead? I also wonder how 'public' my friend wants this project to be as he is not a member of any forums as far as I know.



Well, a T2 tranny would be a lot better in the long run. I'm not sure how far his budget is willing to go. He's funding the project, I just get to work on it. Hurray!



As for the rearend, they say the '84-'85 units have stronger axles but thinner housings leading to easier breaking due to flexing. Some bracing, if we knew where to add it, sounds like a good idea. I'd much prefer to keep the stock rear end instead of swapping to a Ford 8.8 or heaven forbid a big nine incher.



The basics include the shaft, tension stud set, dowel set, mods to two intermediate plates and the stationary gears that fit into them. I'm not sure about the counterweights. I'm also not sure whether we're supposed to send him the intermediate plates so he can mod them and send them back, or if we're supposed to purchase them new through him. I'd prefer to send them down there. How much could shipping cost round trip? https://www.nopistons.com/forums/pub...1047683664.gif



Yeah, ignition will be QLIDFISw/LLS. Quadruple Leading Ignitor Direct Fire Ignition System with Late Leading Spark. I'm sure it'll work great because TLIDFIS worked fine on the 20B before I went with a MegaSquirt (it still has the late leading sparks, which took some work, and sounds like the Pac Performance RX-3, although mine can rev quicker because it's NA https://www.nopistons.com/forums/pub... ). The dizzy is easier to mod for QLIDFIS than it was for TLIDFIS as it only needs two pickups instead of three.



It's fun to write about it. I'm just trying to fit the various bits of it in with my other projects. I won't be able to jump fully into this project until mine are done. I've got an MG Midget 13B conversion to get running and I've gotta pull the 20B out for a teardown in the next few weeks. I installed an RB LT ST flywheel on the 13B today and I've gotta move a few things around in the garage in order to install it in the MG. Too many projects, not enough garage space. https://www.nopistons.com/forums/pub...IR#>/happy.png

He uses a stock front weight and makes the rear weight, but the shaft still needs to be balanced, which he can do as long as you have accurate rotor weights, or you will have to balance the assy here. Its up to you whether you send him the irons and gears or have him supply them. Keep in mind the exchange rate (avg-1us/1.58nz) which helps quite a bit. He figured shipping to be about 1k for the parts you listed, including the irons and gears. So figure about 300 to ship two irons and gears to him.



Dano

Nope, Just a forum member. https://www.nopistons.com/forums/pub...IR#>/smile.png But I do remember meeting you at the last BBQ, my car was not there but I was on my street bike.



I would be happy with it being in either place. I am sure that it is hard to choose a section because this build falls into so many sub-forums. Ie, 1st gen, engine swaps, and this one. I would be happy just to see a thread. https://www.nopistons.com/forums/pub...IR#>/smile.png



When it comes down to it a lot of people do not have the money to upgrade their SA/FB's. A write-up like this is a FAIRLY cost effective and relaible mod if you need to change out your engine. If your friend is ok with it I would love to read about this. And if he is up to it sometime actually take a look at it. He would surely be the attention getter at any meet with a setup like this. This may or may not be his cup of tea.



I have heard the same thing about the 84-85's. I have also heard that you can swap moser axles into the rear-end. SlammedGSL posted about it a while ago. The most important thing to remember about the rear end is that torque is what kills it. If you could brace it in a way that the housing cannot twist you would be far better off. I have quite a few ideas that are mulling around in my head and I plan on putting them to use later down the road once I blow up my current rear end(180k miles). When it comes down to it I cannot justify spending the 1k to get a "good" 8.8" and then after all that loosing hp and gaining 80lbs. Only benefit to a 9" is the ease of swapping gears IMO.



WOW, I thought that shipping would be worse that 300. Let us know what the exact amount is going to be. Are you planning on using stock ignitors? Since you are on a budget I would assume so. I will have to take a look at your dizzy mod on the 20b. I actually have not read through that thread. I love project threads.



There will never be enough garage space. I need a 40x60 shop, and I only have 2 cars and 2 bikes https://www.nopistons.com/forums/pub...IR#>/smile.png

So he'll only need to purchase the rear weight and use a stock front weight then? Cool.



He's got several '83-'85 cores to tear apart. I'll try to find a set of four rotors within one letter of each other if not the same letter. How to I find accurate rotor weights?



We'll be using two GSL-SE intemediate plates for the mounting studs at the bottom sides. I don't feel confident in the front cover mount. $300 or so sounds ok to me. I'll let him know when he gets back. Thanks.

Z, I think I remember you. You were the only one on a bike, and you went with us on the poker run. I was in my friend's orange 1st gen with the orange and black 13B 4 port and the 5" SC. He's the guy who wants to do this 4 rotor.



He actually wanted to do a 20B at first, but since I had already done one and he had so many 12A cores sitting around, it just seemed like the logical choice. A 3 rotor 12A would have been cool, but there is enough room in the engine bay for a 4 rotor, so why not? https://www.nopistons.com/forums/pub...IR#>/smile.png



A peripheral port with Weber carbs is easy enough. Move the tranny back a little, and get rid of the radiator frame to mount a bigger rad further forward, and viola! We won't even need to remove or relocate the front sway bar, as is necessary in a 20B swap into an FC.



There will be an extra 128lbs of engine weight, but the Webers weigh less than Nikkis and a light aftermarket flywheel with an FC waterpump will keep the weight from kreeping up much beyond that. A four pipe header shouldn't weigh too much more than a two pipe or a stock cast iron manifold. Relocating the 40lbs battery to a storage bin should help the front corner a bit. Wasn't the GSL-SE the heaviest 1st gen they made anyway? Meh. https://www.nopistons.com/forums/pub...IR#>/smile.png



The ignitors will probably be GM HEI units since they're cheap and we've had good luck with them before. Yeah, it'll have four ignition modules and four coils. The dizzy will have the leading pickup in the stock position and the trailing pickup wil be relocated to 135° or 225° depending on which direction is easier/more secure. The leading pickup will be for L1 and L2 as they are still phased 180° like any 2 rotor. Likewise the relocated pickup will trigger L3 and L4. Since the dizzy spins at half engine speed, the 135 or 225 degrees away from the leading pickup is necessary to get a trigger event every 90° of engine rotation from the 4 tipped reluctor. That is to say, the reluctor will provide a trigger event to one of the pickups every 180° of dizzy shaft rotation. For comparison, the stock trailing pickup is about 185° after the leading pickup and since the reluctor tips are one every 90° of dizzy shaft or 180° of eccentric shaft rotation, it translates to a trailing spark 10° after the leading spark. If I move the trailing pickup 45° + or - (135 or 225) from its stock position, it'll encounter a reluctor tip 45° after (or before—doesn't matter) of dizzy shaft rotation, or 90° eccentric shaft rotation which is appropriate for a 4 rotor. The late leading sparks allow the use of one pickup to trigger two ignitors/coils/spark plugs every 180° on a set of rotors phased 180° thus keeping the whole ignition system actually quite simple.



If I didn't want late leading for whatever reason (I can't think of one) It would have required four pickups, which would be impossible to fit in that small space, and two tips shaved from the reluctor. This would be necessary for trailing, but since it'll be NA, trailing won't add noticeable HP or help with combustion and emissions aren't even a consideration. That late leading spark is capable of igniting the unburned AF mixture in the trailing edge of the rotor actually pretty well.



The 20B dizzy mod had late leading sparks as well, but it required three pickups in that small space at 120°. They barely fit. The reluctor was stock with four tips although I could have shaved two tips off since each pickup went to one ignitor and then to one coil. Trailing could be done this way on a 20B dizzy placed above the leading set of pickups. I actually did have a double decker with six pickups and two reluctors (one stock for leading, the other with two tips shaved for trailing) but I couldn't justify the expense in running three more ignitors and coils for the miniscule power they would have added. It was NA too so there you go. Now with the MegaSquirt, it still is NA and still has late leading, still sounds excellent and I may go turbo in the future, so who knows. https://www.nopistons.com/forums/pub...IR#>/smile.png



Rear end bracing. I'm sure that's something he would consider. We would just need to know what to do and where to place it. He actually broke several rearends in the MG Midget back when he was the owner. I got it from him in '96 and have tinkered with it off and on. Part of the problem was that the shop installed a '71-'73 engine with its heavy 30lbs stock flywheel. Racing Beat didn't offer an aftermarklet light flywheel for it because of those engines' "characteristcally poor low RPM torque". Something about carbon apex seals and low RPM... Well, I installed my REPU engine complete with its stock heavy flywheel and could chirp them at just above idle. We're talking a 2kRPM burnout. https://www.nopistons.com/forums/pub...IR#>/blink.png 2nd gear scoots were like nothing. This prompted me to try at least a light steel flywheel. Oh man, it was a major improvement. It accelerated extremely nicely after that with less danger to the rear end. It's geared with the taller 3.7 so I suspected aluminum may not be as fun. Then again, the car is so frightingly light. Anyway, the light steel is going back in since it appeared to be the perfect middle ground, and it was already sitting here. I'm also swapping to an FC clutch master and slave cylinder since the stocker is too small for the 1st gen slave it's currently using. It's advice from RX-Midget. The pedal is just way too stiff even with a stock 215mm pressure plate at the moment. I may take it to the BBQ if it's done in time. I doubt the 4 rotor will be done by then, but you guys could talk about it if he can make it there this year.

$296.43 Global Express Guaranteed® Document Service through USPS from Iowa to Auckland.

Can FedEx ship to NZ? I can get a discount.

and that was for a 40 lb shipment (2 irons)

I tried to do a quote online and it was being a biatch, so I just went to USPS. My quote was also valued @ $1.00

I see. Used plates = low value. https://www.nopistons.com/forums/pub...#>/biggrin.png I'll have to find out if FedEx is similar.

Great information in there Jeff. I can now see how you plan on running the ignition...



That was me. I was the only fool that was on a bike, too bad it was not a rotary. Eventhough one rotary can be headache enough...



I do remember your friend. I talked with him for probably about 15mins last year. I kind of picked his brain because I had yet to see his car. I like to see things that don't come around. I liked his car...the SC was even painted https://www.nopistons.com/forums/pub...IR#>/smile.png And IIRC was kind of like a orange bumble bee...

My work has a fedex account and I've noticed that the invoices are always more than the shipping reciepts, Ill have to look closer and see where the extra charges are coming from https://www.nopistons.com/forums/pub...1047683561.gif . Nonetheless its still way cheaper to send out used/good parts if you already have them laying around taking up space. I dont have any spare parts lying around so I'll have the extra cost of the irons and gears.

I have not asked how accurate the figures need to be, or even what unit of measure. I would assume all he needs is a dead weight. I just planned on sending all four of mine out to be spin-balanced and weighed just to be sure, that is once I get all of them. I have annother month or so to figure it out though https://www.nopistons.com/forums/pub...IR#>/smile.png