Greddy Turbo

Greddy Turbo for 1.6l Miatas

[10/27/2003] Reviewed by: Fadi

Applicable to: '90 - '97 1.6 liter

4.5-5 psi turbo kit for NA6 Miatas. Kit included: exhaust manifold, turbo unit, intake pipes, airfilter, nuts and bolts, oil lines, gaskets, instructions 9in Japanese, fuel pressure regulator, fuel lines, and vacume hoses

Over all I'm satisfied with the product. Took about 10 hours of easy work to install. I wish Greddy would listen to the Miata community, and make a better manifold with the 'cuts' already made. The airfilter is very cheap, you can see right thru it! Not pleased with the placement of the air flow meter, or the turbo to air tube pipes, very restrictive, and rattles.

A bunch of little problems that any project is not free from, but I expected a little more from a company such as Greddy. Overall, I give the kit a "B+" Would have been lower, but I gotta give credit for the cost factor. $1200 for another 35 hp, you can't beat that.

Difficult to remove without leaving damage

[3/26/2003] Reviewed by: Tom Mak -

Applicable to: '90 - '97 1.6 liter

Affordable turbocharged system for 1.6L Miata. At stock level, it increases hp by about 30-40rwhp

Everything came from the package worked fine with the exception of bad nuts and bolts. Just go to local hardware store and get them. Its a job that takes less than 10 min and cost less than $10

It took my friend and I almost 9 hours to finish the whole job. While the whole job is not hard, its more just a time consuming job. There were some parts that Greddy supplies came as a very tight fit. You really got to fiddle around to get everything in. Highly recommanded for 1.6L cars

Difficult to remove without leaving damage

[12/19/2002] Reviewed by: chun wei chen -

Applicable to: '90 - '97

kit comes with turbo standar size on 1g Eclipse 15g , Manifold, 2 pipes for intakes use along with stock intake tubes, oil lines, some bolts for the down pipe,some heat cloth, gaskets. took 6 weeks after order to get it.

kit is easy to install, just the oil return lines and feed line don't look very good, too close to hot exhaust and moving parts under the hood. make sure to soak the manifold down with PB blaster over night before install that will save you from braking bold when remove manifold.

kit looked cheap for $1300 you get what you pay for, as of power gain is not bad running at 6 psi, probably put you in high 15's. i wish i never order this kit cause now i will probably spend same amount the money try to upgrade this kit to 12psi as the FM kit. if your goal is to get 10 to 12psi on the turbo i will highly suggest go with the FM kit. save all your money and do it at once. save time and headch try to figure out what upgrades works with Greddy. FM probably gives you more clean looks in your engine compartment then Greddy. most greddy kit i see with upgrades just don't look as good as the FM kit.

Difficult to remove without leaving damage

[11/12/2002] Reviewed by: Andy Folyd -

Applicable to: '90 - '97 1.6 liter

Turbo kit that fits the 1.6L miata. The kit doesnt include much from the get-go..just enough for you to run 5.5-6psi of boost. Thats still much faster than a stock miata is, but you will soon grow tired of just 6psi If you are anything like me:)

The kit is not a complete kit like a FM turbo kit. However, the GReddy allows you to upgrade at your leisure and can be made just as fast as a FM with a standalone ECU and 12-15psi of boost. The GReddy TDO4H-15G turbo is bigger than its size. The turbo is a little bit laggy(with the stock exhaust) but with a full 2.5in turbo back like I have you should see 12psi somewhere around 3600-3800rpm which is not bad at all, and on par with the FM kits. The turbo is so fun, and it really screams at 12psi.

The only problem I have with the kit is the manifold, it has been known to crack and the bolts that GReddy gives you are complete junk. Replace all the bolts with Grade 8 bolts, and make sure to use anti-seize on all bolts. I learned this the hard way when a bolt sheared off in my manifold. Other than a few quirks the kit is great fun.

Difficult to remove without leaving damage

[7/7/2002] Reviewed by: Chad Smith -

Applicable to: '90 - '97 1.6 liter

Non intercooled Turbo kit.

The kit took about 10 weeks to arrive but it was worth the wait. It can't be beat for $1200. The car started up right after the installation. I did have to upgrade my tired fuel pump. The pump was fine for a few days and then could not keep the pressure steady.

The kit installed in about 6 hours. There is not anything exceptionally difficult about the installation. At 5psi the car runs 0-60mph in 7.3 seconds and the 1/4mile in 15.27 seconds (with the Bipes ACU and 14deg static timing)

Over 30 minutes to remove completely

[2/13/2000] Reviewed by Nathan Ramsey -

Applicable to '90 - '97 1.6 liter

Entry level turbo kit for the 1.6L engine only. Comes with a turbo exhaust manifold, turbo, downpipe, intake pipes, air filer assembly, and misc. hoses and fitings for oil and vacuum signal.

Took a while to get (4 weeks...was on back order to Japan) but still quicker than a BEGI kit (I have heard 10 weeks). Kit was complete, except for one bolt that was too long...this piece was easily found at a hardware store. This bolt was at the bottom of the turbo housing where it meets the downpipe...can't fit the longer bolt in that tight area.

Install went well, about 10 hours but could have done it faster if I hadn't been working at night 50% of the time. Hardest part is getting the bolts for the turbo, manifold and downpipe started...its just really tight working room.

Once on the car though...WOW. This is a new car. Great feeling and I've just had this kit one day. Very nice increase in power. Will give you grins.

This kit is probably not the best for someone looking for major power. It can be upgraded but you'll end up spending more $ than for a comparible FM kit...great basic package though if you don't have alot of $$$ (kit cost me $1300).

I have heard of stories of cracked manifolds...I had mine ceramic coated and the flange cut to help eliminate the expansion stress that can occur with hot turbo parts...we shall see how it holds up. But so far I am thrilled with the kit.

Over 30 minutes to remove completely

Reviewed by: Jay Reyes -

Turbo to turbo down pipe gasket wears out to quickly and is hard to get replacement part.

It's been going four months since I've ordered the part and still no show. Car won't pass CA. Smog check because of excessive emission from gap is between parts.

Ca anyone tell me where I can get this part hopefully faster than when I first ordered it from, even if the part comes from my first order I will keep it because it is a part that wears out quickly.
Difficult to remove without leaving damage

Reviewed by: Miguel -

Greddy (TDO4) Turbo kit

Ive had it for 6 months now. Only major problem is the hose connecting the turbo to the intake. I think that the way the arm was bent is done all wrong. Someone told me that if you use an HKS arm it would eliminate the problem. I used a longer connecting hose, and it solved the problem.

I think its a great addition to an already fun car to drive. Im boosting about 4 pounds now cause my tuner doesnt want to put the boost up till I get my exhaust. Ill have to say though, that the Miata runs alot better with a blow off valve. I drove a Miata with the same turbo, but without a blow off valve. It felt all wrong! It felt as if the turbo was going to blow from the pressure surge. Especially on the lower gears. If you have any plans on turbo charging your Miata make sure you have a blow off valve in your budget. And it sounds cool too!

Difficult to remove without leaving damage

Reviewed by: Percy M. Chow -

Bolt in turbo kit for the Miata. You get the turbo (mitsuishi TD-04H), GReddy exhuast manifold, aux. fuel regulator and hose, clamps, etc.

You'll need and HKS elbow (or entire powerflow intake) as the GReddy tubro out of the box tends to pop off the stock intake system under boost. The HKS intake elimates this problem as it replaces the stock accordian elbow on the 1.6 intake tract.

Other good upgrades are a Blow-off valve (this'll need to to kinda tough to put on as you'll need to drill out the intake side and turbo side of the piping) and an MSD 8662 boost unit (which will alow you to run up to 14 dgrees of timing as 6 dgrees kinda lags at low rpm)

With the upgardes of an HKS intake, BOV and MSD, you'll easyily get Sebring-like power at just uner $1800.

Add a used Intercooler and dial up the boost to 8 psi and see the Mustangs go away fast!!!!

Updated 8/16/98

Well, I've had the Greddy kit in my car for over a year. It's power has been pretty good as well as the overall upgradeability.

I've added a Blow-off valve and and Intercooler from an 89 RX-7 and the car pulls much better mid-range and freeway.

My only real complaint about the system is the exhuast manifold. It has cracked and this same crack is appearing on a friends turbo cars as well. This after only a years worth of use. I called Greddy and they are replacing the unit but since I am out of the warranty stage, looks like I'll have a $400+ bill for it. The Greddy Customer service guy was really nice about it so I'm not too worried yet. But the unit will most likely take close to a month arrive as it is coming from Japan.

As a final review, it's a good kit for the money but until they fix the casting of the exhuast manifold, it's not a good buy.

I recommend saving your pennies for the Bell turbo or better yet, swap into a 1.8. :]

Updated 5/16/99

Ok, not like I'd write home to mom about it.

Here's an update on the turbo manifold of mine that cracked.

I de-installed my turbo last August to drop in a 1.8 motor. Since the turbo unit was still under warranty, I contacted Greddy for a replacement manifold. They said, no problem, we'll get a replacement, can you wait a month. I said ok.

1 month goes by, then 2, then 6.

Turns out they wound up re-casting all the turbo manifolds. So last week I called GReddy and they got the new manifolds in [finally]. And for the handling fee of $150 I can have it.


But what's a turbo kit without it? So buyer beware eh? The guys at Greddy was pretty nice about it and I don't go ballastic about stuff usually anyway, but this instance helps affirm my distaste but incomplete equipment and japanese aftremarket quality.

It sucks.

Reviewed by: Richard Dekker -

GReddy turbo kit for 1.6 litre Miatas. Caveat on instruction manual states that it's for non-ABS cars only, although you can ignore that.

I was in on a bit of Steve Searle's installation, providing tips and an oil fitting (Steve's broke with an internal casting flaw) and did my own recently. Despite the fact that on the floor, the kit goes together quite well, in the real world, draped over your fenders, there are a few things to do prior to installation.

First off, some of the bolts supplied by GReddy are too long, specifically the four for mounting the turbo to the exhaust manifold (supplied 1", required 3/4" long) and one of the four bolts for attaching the down pipe to the turbo (supplied 1-1/4", required 1"). Other than that, you'll need one more hose clamp for the oil return hose, as the one supplied needs bolstering, as the hose is bigger in diameter than the fitting on the block. I, on Steve's urging, also bought some heat tape to wrap some of the hoses and wiring near where the exhaust down pipe ends up, along with the under surface of the engine hood above the turbo.

Installation went very smoothly, and took three hours with the help of my Mazda mechanic, Carl Modine of RX Heaven in Edmonton. He came up with a few improvements to the kit's instruction manual (which could do with a major improvment of it's own), specifically in the neighbourhood of the auxillary fuel pressure regulator's fuel hose routing.

I'm working on getting a better elbow fitting at the throttle body connection, as some GReddy owners have reported that the stock hose starts to slip off over time.

Although I'm still in the 500 mile break-in stage, the car definetly has improved performance the closer I get to the 4,000 rpm specified redline during the bearing's break-in. We'll see if I can't catch Steve yet.

Things to notice with the kit on: muted exhaust note (thankfully, I can still hear my Borla, unlike Steve whose car is quite quiet), lots of intake noise (louder than the exhaust), some turbo whine (nice addition), and the flapping pop-off when you take your foot out of it.

All in all, for the $1700 Canadian that I spent on the kit, it should be all that the car needs (I do drive it in winter, so the Bell's huge bhp gain would be a handfull on snow and ice). The power gain is what the car should have had from the very start.

Reviewed by: John Bercic -

Turbo + msd. boost sensitve timming retard + manual boost control + exhaust = AWSOME, MOST BANG FOR $$$$. In total about$2600.00 cdn. $2000.00 turbo msd $200.00 manual boost control $100.00 custom exhaust $300.00

1990 Miata automatic :( ( i know. )with 178,000 km. Instructions aren't great. Kit was made for right hand drive (Japan). Some simple mods were needed to make it all fit under hood. Factory boost set at 5.5 psi. I have mine set at 8psi. Thanx to manual boost control. Get it but don't get to boost crazy. With 94 octain gas I have no problem with the car. MSD.timing retard is also a must off the line performance is weak mainly because my car is automatic but let me get to 4000 rpm and its see ya ! The car pulls like crazy to 140mph. And thats it governer kicks in. Best way to discribe the power is when your miata starts to die mine is coming to life. get it it is awsome. Greddy I'm not impressed they know that the kit is for right hand drive they should offer any one with this kit a replacement part to fix problem. Greddy are you listening. awsome power an honest 50 to 60 horse gain. a miata is not a miata until you apply a little forced induction. Ask any one who has done it and I bet they would say they would do it again.

Reviewed by: Steven Searle -

Turbocharger system for 1.6l cars

The installation was fairly simple, if you discount the fact that the custom oil fitting for the pressurized connection from the engine block to the turbo sheared in half with less than 8 lb-ft of torque. If my friend Richard Dekker hadn't given me his (we both bought a kit at the same time), I would probably still be walking.

The car started the first time, which pleasantly surprised me. First thing I noticed is that there is no exhaust note at all now, only intake growl and turbo whistle. The car definitely feels stronger at low rpm (I installed a J&S active knock-sensor beforehand, so my timing is still at 15 degrees BTDC). I had to exercise some major restraint at first, since Greddy recommends a break-in period of 300-600 miles where you cannot exceed 4000 rpm. Unfortunately, this is where full boost occurs, and the fun is starting. Oh, the frustration.

I broke through the break-in period within 4 days (lots of aimless driving, only this time at night after work), I finally got to stretch the car's legs. I don't know if you can see the smile on my face.

The boost starts at about 3500 rpm (keeping in mind that there is no loss in drivability below that point because of the J&S) and builds smoothly through about 4500 rpm, where it seems to peak (I still haven't installed the boost guage, so these are estimates only). The rush of power through to the redline is smooth and oh so satisfying. The car feels genuinely quick now, where it felt somewhat strained and lethargic before. Part throttle response is excellent - way better than stock.

0-60 is about a second quicker than before (about 9 seconds with a relatively easy start). More serious acceleration happens at highway speeds though. 0-100 mph times have plummeted to about 20 seconds - an absolutely huge improvement.

Strangely, in the 2-3 tanks since the break-in period ended, my mileage has gone up about 10 percent. Maybe its all that extra torque.

This power increase, although not as serious as some of the other kits out there, is just what the doctor ordered. The car has the kind of easy, effortless power that I always thought it should have had from the factory. Minivans no longer run over me at stop-lights anymore, and that, more than any other reason, make the the upgrade worthwhile.

Back to Product Reviews 22 November, 2003