Kevvsworld

Hello everyone, my name is Kevin, and I just picked up a '93 Del Sol Si with the D16Z6 mated to a 5spd trans. I apologize in advance for the length of this post.



I have been reading for days. I have read so many suggestions and combos, that it is a bit overwhelming, so I decided to reach out and ask for help (even though my research indicates I will be flamed for not doing enough research....please be kind)

First, I am 41 years old. I am a high school math teacher, and I am not a boy racer...anymore. Not that I have a problem with boy racers, just that's not who I am now. In my youth, I owned an '88 tbird with the turbo 2.3 for around 15 years, and I wrenched on it the whole time I had it. T3/t4 hybrid, FMIC, 255 walbro, Kirban FPR, 3" downpipe to dynomax, etc...I absolutely loved the feel and sound of the turbo, but I always wished it was in a lighter car.

I need some guidance with the del sol. I will lay out what my goal is since that seems to be the first question asked:
I would like to keep the Z6 and turbo it.
I don't want to do a swap.
I am looking for 200 to 250 hp at the wheels.
I am not made of money, but I have extra income, and I am in no hurry to get my project done, so I can buy parts over time and build as I go.

My daily is an Infiniti G35 Coupe. The del sol was bought simply as a project. I'm not looking to drag race it. I just want a nice peppy fun car that I can turn wrenches on and that has that turbo feel and sound that I miss so much.

The car is a bit sad and in need of some repair. I know all this needs to be done before I ever think about the turbo, and I honestly can't wait to jump in and start! I bought the car from my buddy who is the 3rd owner. The car currently has 256,000 miles on it. Yikes, right! It burns about a quart of oil ever 1500 miles or so, so the rings are most likely shot. No leaks, so it's going through the engine.
The plan right now is to replace pistons and rods in preparation for the future turbo. The new rings on the Pistons should take care of the oil loss. I have read that the Vitara was a good turbo piston, but some people think the quality has gone down over time? Looks like eagle rods are what most buy to mate with their new pistons, but if Vitara is indeed still a quality piston, they sell a kit with rods included. Why not use those? Because of the block notching? Is block notching not necessary with the eagle rods? I would not like to put together a turbo kit from different sources. I like the idea of the piping being pre made for my application. I have gone down the custom piping road before, and I remember having to get my son to use his skinny arms to help me form it up in the engine bay...no thanks.
New bearings for the new rods, of course, but would the crankshaft bearings be okay at that mileage? I have watched a few videos showing that the Pistons and rods could be swapped with the engine still in the car, and I would LOVE not to pull the engine if I didn't have to.

I am not sure what kind of trans I have except that it is a 5spd. The clutch pedal needs a couple pumps to get the car to go into gear while running. Fluid looks fine. Could be the slave? Does the del sol use a normal slave cylinder set-up for the clutch? Sorry that is such a noob question. The engine stuff is quite similar, but the front wheel drive trans is alien to me.

Here are my main questions:

Am I crazy? Is this a doable project on this high mileage car?


If the project can be done:

What piston/rod combo would work best for my 200-250hp target, and what is a good source for these parts?

Is there a turbo kit that exists for my goals, and what is a good source for these parts?

How much clutch will I need for 250hp, what is a good brand for this application, and what is a good source for these parts?

Is there a go-to rebuild kit (gaskets and such) for my application?

What problems should I watch out for?

Does anyone know a good tuner in the northern Arkansas, southern Missouri area?

Thanks so much for reading if you made it to the end. I look forward to learning about the Honda, and getting to know everyone!

Kev

NotARaCist

iTrader: (1)

https://honda-tech.com/forced-induct...2A%2A-1024174/

You don't need pistons and rods for 200. The stock rotating assembly can handle that just fine.

If you want a kit, go autoworks is a popular go-to. If you're willing to put in the effort, you can also piece together your own kit and save some money.

When I was running a 200 WHP turbo D16, I used a Competition Clutch "stage 4" 1620 Street/Strip clutch, with the standard diaphragm. It held with zero problems, wasn't too bad under the foot, and was manageable for stop and go traffic. That's what I personally recommend. You could also go with an Exedy Racing "stage 1" clutch. Note, though, that I put "stage" in quotations. One company's stage 1 is another company's stage 2 is another company's stage 97. Don't try to compare clutches by their "stage". Look at their rated torque loads. If it doesn't have a rated torque load, or if it has a horsepower load, then ignore it. As for source, I got mine from ClutchFlywheel - Clutch, Flywheel Superstore - ACT SPEC Fidanza Competition Clutch Exedy Clutchmasters Carbonetic ATS - Homepage back in the day. No problems that I can remember.

On that topic, and speaking from experience, stick with an OEM flywheel. Lighter is not always better, and lighter will make the car a pain in the dick to drive at low speeds (parking lots, stop and go traffic, **** like that)

You can never go wrong with OEM. That being said, my current build is running complete Cometic top and bottom end gasket kits without problems.

Poor maintenance. Proper break-in for the clutch. Proper break-in for the motor, if you decide to rebuild it (which, again, you shouldn't need to unless there are other issues you haven't mentioned). Proper tune. This is not optional.

https://honda-tech.com/forced-induct...ry%2A-2349805/

The regional subforums might also be useful to you.

Kevvsworld

Thanks for the input! A couple of follow ups...
The rings are definitely shot, let's say my hp goal is 250. Would stock internals still be okay? I could hone the cylinders, put in new rings, and go with some fresh bearings since its apart, and a 257,000 mile engine will still hold boost? If so, Honda engines are amazing.

I looked at go-autoworks. 2 grand for their basic set up, and I don't see anything in the way of engine management. Is it up to the user to source engine management? Or is the computer module of the d16 able to be programmed by a tuner? I'm not sure how this is a "kit" in the sense of the word I understand it to mean. They are probably popular because of quality, I'm guessing?

I could piece together a "kit" if I knew what in the world I was looking for. I read through the "this is what you need" faq section, but it is extremely vague...turbo, manifold, intercooler, etc... Is there somewhere I could look to get specifics for my 250hp goal? I would need to know things like which computer best suits my setup, what wiring needs to be changed that is specific to the del sol platform, and where to find any parts I might need. This is why I was looking for an all inclusive kit, because people in-the-know are easily angered by those types of questions.

My goals are different than most, so a LOT of the information I read doesn't help me. It is mostly about 400+hp track beasts, and I am looking for a fast and fun around-towner. That's why your clutch info was EXACTLY what I was looking for. Thanks again!

Kev

hondur

iTrader: (1)

The stock rotating assembly on d16 engines is generally considered safe to the point of 250 wheel horsepower. People boost them up to 300 and they still run for a while.

Depending on how bad the piston to wall clearance is after being honed, or if the cylinder is out-of-round, you may need to bore the engine and get new pistons.

NotARaCist

iTrader: (1)

250WHP would be pushing it on stock internals. If the rings are shot and you have to pull the block apart anyway, Eagle rods are the golden standard as it were. For pistons you have options. Personally, I'm using Wiseco in my build. CP and Supertech are also good options, though. If you do decide to go with forged internals, raise your static compression ratio a bit. Stock is something like 9.2:1, IIRC. Get some pistons in the 10:1 range.

If you're OK with the bottom end of your originally stated goals of 200 WHP, that's entirely doable on the stock motor. If it needs rings though, it needs rings, and a proper rebuild should be in order. It sounds like you understand what that entails - all new seals and gaskets, bearings, rings, and hone. You would also be silly to not replace your timing belt, water pump, and tensioner while you have everything apart. Again, though, for those parts, OEM is what you should be getting. Yes, Honda engines are absolute beasts, as long as you take care of them and stay within their limitations.

Any "kit" you find won't include an EMS - that's always going to be separate. The stock ECU cannot be re-tuned, but it can be socketted, which allows for a new chip to be put in. A tuner can tune your car, and cut the tune onto that chip for your ECU to use. There are a lot of different EMS options out there, though - the best thing to do is decide who you want to tune your car, tell them your goals, and see what EMS they want to use. The tune is an extremely important part of any turbo build, and if your tuner is most comfortable with one piece of software over another, let them do what they're comfortable with. Hell, sometimes it'll even be cheaper that way, too.

The basics for a turbo kit are the turbo, manifold, downpipe, oil feed and return lines, charge piping, and intercooler. Some turbos will also need coolant feed and return lines (this is a good thing to have). Beyond that, you'll also need injectors that flow enough gas for your goals. DSM "blue tops" are 440cc/min injectors, which is great for a 200-250WHP goal. They're cheap (~$150), easy to find (literally all over eBay), and plug right in with extremely minimal modification (just need to Dremel out the lower seal a tiny bit), which is great, too. You have an OBD1 car, which makes your life considerably easier as well - no need to worry about IACV conversions, or adapter harnesses, or resistor boxes, or any of that **** us 96-00 guys have to deal with.

hondur

iTrader: (1)

Sorry about my last post, i wasn't thinking. I'm going to try and do a better job of answering your questions this time.

Piston rings aren't your only concern with the oil loss issue. Your engine undoubtedly needs exhaust valve guides too.

You need to notch the block with Eagle rods. There are "vitara kits" that come with "custom length rods", these raise your compression ratio back up a little (vitara lower it). For the price point of $500, i don't think you can beat it. Not when Wiseco pistons cost $750.

I think you should pull the engine out. They've very light engines, i've carried them up flights of stairs on a few occasions. All aluminum engines are g r e a t.

Replace your crankshaft bearings, King and ACL bearings only cost $50 each (crank and rod). Even if they're completely without wear, I say change them anyway for the peace of mind.

You can buy intercooler piping off Ebay and be perfectly fine. There's dozens of choices, just make sure you get some that has positive feedback.

The transmission has a one inch circle on it, it'l say either a000 or b000. This tells you which transmission you have. On that note, you probably have the original motorset in your vehicle. The D series engines have a regular slave cylinder, nothing integrated into the inside of the case like ford trucks.

I used FelPro cylinder head and block conversion gasket kits (top and bottom, respectively). Keep in mind, they do not have any of the intake manifold gaskets which i think be changed based on the mileage in your car. You'll need to get these from Honda. I like to buy my OEM parts from majestic honda, they're a retailer out of RI that has the best prices. If you're spending more than $50 on parts, their high shipping & handling price becomes very bearable since you'll be saving money over the local dealerships.

Kevvsworld

Excellent info! And I really appreciate it!

Why would I want to raise my compression if I intend to turbo the car? Is it because my turbo will be small for my power goals, and my use of the car for zipping around town necessitates a higher compression ratio for more pep down low?

There is such a variety of turbo choices that it becomes overwhelming. With my old tbird, Stock in ran an IHI turbo which was super small but spooled fast. Upgrades included a T3 turbo in either .48 or .63 trim. The 63 was for more top end, and the 48 was in between the stocker and the 63. You could go aftermarket, and that became a confusing mess quickly. That's how I feel when looking at the variety of turbos for the Honda. Any recommendations for the turbo?

Kevvsworld

No worries on the original post I will take all the info I can. I am learning and soaking it all up. I appreciate the follow up, and all the help!

Kev

NotARaCist

iTrader: (1)

Short answer on the compression thing: Because higher is always better, up to the limits of the fuel you're using. With the tuning options available to us today, there is absolutely no reason to lower compression. Screw Vitara builds - we aren't in the 90's anymore. It's time to move forward into the 21st century.

There are a lot of options out there, but remember that you get what you pay for. Garrett is the go-to, and a GTX2860R would be great for you. STC is another good option, although I don't know if they build anything in a good size for your goals. When I was running my 200 WHP D16, I ran a TD05H-16G. It made for a fun drive, good spool, and it held power all the way through to redline.

A couple other things that I forgot to mention. First off, fuel pump. The stock pump can technically flow enough fuel for 200, but that's only technically. You really should pick up a Walbro 255. There's a vendor in the performance marketplace that sells them for under a hundred, with the needed install kit. You want it. A second thing, head studs. Never re-use OEM head bolts. Since you have to replace them anyway, it would be an extremely good idea to upgrade to ARP head bolts. They aren't much more expensive than OEM, and they have much better clamping force than OEM. It's well worth it for the added insurance. You're fine with OEM main bolts, though.

hondur

iTrader: (1)

You should also give the suspension/brakes a close inspection. Being that your car is well over twenty years old, you're probably going to need to change a few parts. If you need new rotors and especially if you need calipers, i recommend upgrading the front calipers and rotors to Integra Type R parts. They're 11.3 inches instead of the 10.3 inches that come from the factory on Si del sols.

What i would recommend:

Jack up car, put on jack stands and double check that it's secure by pushing the car around a little

drain all fluid, disconnect hoses and then wiring.

remove wheels (may need to loosen lugs first, if you don't have an impact wrench). Remove spindles then axles.

Remove the engine mounts and then pull the engine out. You can even do it without a cherry picker, there's a DIY write on here for that.

Seeing that i believe you're competent in engine assembly, take everything apart and bag it up. Label everything very specifically.

Bring the engine block, cylinder head, crankshaft, rods, pistons, and valves to a GOOD machine shop. Put $50 in his hand, tell him it's a tip. Get the block, crank, and head hot tanked or power washed. Tell him you want a after-hone PWC of less than 2.5, or else you're going to bring him pistons and it needs to be bored. Call him up to check if the cylinders and pistons are going to be good, . Don't let him bore it before you bring the pistons or else the PWC may not be perfect and it could reduce the lifespan of your engine. If the cylinders aren't out-of-round and the after-hone PWC is less than 2.5, you're good to go to have the pistons/rods media blasted or hot tanked / power washed. The machinist should know to spray the **** out of the wrist pin with WD40 to prevent water from being in there and rusting if they are actually washed and not blasted.

You could do the out of round check yourself, you could even hone it yourself, but the necessary tools are expensive and it takes a lot of expertise in engine work to do it right the first time. The machinist should charge you $500 or less. If it needs to be bored out, it might be $650. This is in my region, your prices may vary but shouldn't be more. I live in the north east, everything is over priced here. I know a guy in georgia that would get this all done for $250.

Have the valves ground, cylinder head and block resurfaced (for good measure, i know that they're probably not warped). Get the crankshaft polished. Get the valve seats cut. Get the exhaust guides replaced. Maybe he'll want to do other stuff, hear him out he might have good ideas.

Bring it all home, clean it all yourself to get rid of machine shop dirt and dust. Assemble everything according to the FSM directions. Change out the head bolts for ARP head studs and follow their torque spec and procedure instead of Honda's.

That's a basic idea of what you'll be doing. There's an awful lot more to it than that, this is at least 50 hours of work, but it'l be fun. I promise.

NotARacist, is there anything wrong with what i said?

P.s., "it'l be fun. I promise." is what my machinist told me to get an extra couple hundred dollars of labor out of me. I was only going to have the head resurfaced. I was going to replace the guides and cut the valve seats myself. He gave me a good price for all the machine work for a full and proper rebuild. I did it, so did NotARacist. Trust us, we're DIY experts.

hondur

iTrader: (1)

IMO, you should be able to get a sufficient turbo kit for a grand. Buy a junkyard mitsubishi turbo (NotARacist choose TD05H-16G, I've got a 13G for faster spool) rebuild it yourself and have it balanced for $50 (that's what i was quoted on here). Buy ebay intercooler piping. Buy a real wastegate, blow off valve, silicone I.C.P. couplings from a reputable company. Get a good rebuild kit for the turbo as well, that'l be like a hundred bucks. A good condition used turbo manifold is gonna be like a hundred bucks.

Of course, this doesn't include a tune... You can modify the factory ecu, a lot of people do. You can buy a megasquirt for $200, most people hate this idea but i like it (it's a lot of work, you need to be a tuner or someone who's read about tuning, wiring, and engine-ering for hundreds of hours like i have). After spending like two years looking at honda-tech, i can safely say i'll pass ASE certs. I'll get an A in UTI while sleeping in class.

Almost everyone gets their stuff tuned for around $500. Make sure it isn't just a W.O.T. tune.

eghatch9295

iTrader: (1)

as to a lighter than stock flywheel, i go civic vx. honda OE quality, 15 lbs, 9oz. stock z6= 19lbs. not too aggressive, but gets the job done. like blowing apart axles and wheel hopping all over the place? me either. i noticed solid advice about the motor/kit, but nobody really touching the transmission side of things. LSD my friend, not the kind that makes you see ****, the kind that takes you from a one tire fire to able to hook. avoid the hell out of OBX, my personal recommendation is Mfactory. I have one and love it. while you're in there, plan on at least a refresh. my guess is your 3rd gear looks like crap, or at least synchros. luckily for you, parts are abundant, not terribly expensive, and in the realm of transmissions, easy to swap. if you do indeed have the original z6 transmission, good for you, that's the one you want to have. Is this a ex/si tranny 96+ how can i tell? - D-series.org is the only way to positively identify a pre '96 d series transmission.

Kevvsworld

That's a heck of a list! However, if I was going to pull the engine out of the car, I would just drop a lower mileage z6 with good compression back in it and call it a day. (And save a ton of money)

I'm not looking for a race car. Hell, I'm not even looking for a built car. I'm just looking for a fun weekend car that lets me feel the boost. It would even be fun for me to have to wrench on the thing occasionally.

After reading a ton more, I'm gonna get the cylinders checked by a shop. If they need honed, fine. If they need bored, I'll start looking for a replacement engine. I will let the shop do the honing since they already have the tools and the know-how. Then I will let them swap the Pistons while the head is already off. They will also have the know how for correcting ring gap, which I don't.

Probably gonna go with stock Pistons and rods since I can't seem to find specific info on an alternative. Higher compression ratio Pistons are suggested above, but without details, I still don't know what I am looking for.

I'd like not to have to notch the block as that would turn into something either I would be uncomfortable with or the shop would charge me out the *** for.

All this will take place after I run a compression test, change the oil, and get any other maintenance items sorted out. I will eventually need a stronger clutch, so that is high on the list too since the clutch seems a bit weird at the moment.

Kevvsworld

Now that I've written all that out, I think I might check around for a replacement z6 with lower miles anyway. I can probably find one for less than the price of the shop work. I need to get all this sorted before I start worrying about the turbo stuff. It will just give me more time to learn. I'm in no hurry.