internal needed for turbo to work on a 1996 mx-3 4cyl dohc

kami_no_michi · Post by **kami_no_michi** » January 5th, 2007, 11:33 am

hi ive posted a few questions on this forum and to be honest im just confused more than informed. basically my mx-3 has 108000miles on the clock i do want to turbo my car but im worried if i just slap the turbo on and get it running ill just blow my engine to bits. my goal is around 160bhp but wot sort of gain am i looking at if i just put the turbo on standard? 130/140bhp. its annoying aswell cus all i ever here on most of my threads is BUY A BP. guess what i live in england and if u can show me where i can get a reconditioned bp engine i will but i just cant seem to find them. this also seems a easier route to take since my engine swap is zero. i know with the corksport intercooler i can run at 12 psi which seems decent and i would be happy with that. but wot would i need to upgrade internally to make this a reliable 12 psi where i could use it to drive to work everyday aswell have my fun on the weekends???

ps also i know my ecu is obdII which apparently will make it harder to turbo my car is this true or am i once again getting mixed up with the information on forum.

nickmx3 · Post by **nickmx3** » January 5th, 2007, 6:01 pm

You can get the bp engine from the mazda astina 1800 that u have in england or from another mazda not too sure if its a 323 or protege it has a close ratio gear box i think they were only sold in europe.

kami_no_michi · Post by **kami_no_michi** » January 5th, 2007, 10:02 pm

the only 323 i can think of in the uk is 323F my friend had one and i beleive it was 1.8 dohc would this be a viable swap?

JWMotorsports · Post by **JWMotorsports** » January 6th, 2007, 12:22 am

With good tuning a B6 can take 300WHP on a stock bottom end for a LONG time!

My first motor was a B6T out of the Mercury Capri XR2. I rebuilt it with off the shelf parts, honed the cylinders and put it back together with a Fel-Pro MLS head gasket and ARP head studs. It took 26psi of boost from a Garrett GT3076R (big GT30R, aka GT3037 also) on pump gas for over 10,000 miles of daily abuse before finally snaping the #1 rod just below the wrist pin from cyclic metal fatigue. These were the SMALL B6 rods also found in the Miata B6's and MX-3 B6's. The 88-89 323 GTX engines have larger rods that would take 400WHP for a long time.

Long story short...12psi ain't squat for a B6 unless it is a REALLY tired motor. Also, psi doesn't mean that much...what matters is how many lbs/min or cfm of air the turbo flows per psi of pressure. Keep it cool with plenty of fuel and it'll LOVE it!!!

kami_no_michi · Post by **kami_no_michi** » January 6th, 2007, 7:56 am

well i thought 108000miles was a large amount of miles for the engine so i imagine the engine must be getting pretty tired. Are the b6 engines really that good and can take that much of a beating just by going sttraight turbo and not upgrading the internals of the car. Would the miata cams and the carillo rods from corksport( check speeling ) be a good idea to get. like i say im not looking for any massive bhp gains. i dont want a 250/300bhp car.....yet. im just looking for 160-200bhp im just trying to source out what i will need to achieve this while making the car very reliable

94blaze1.6 · Post by **94blaze1.6** » January 6th, 2007, 2:37 pm

listen to jw, he knows what he's talking about....

10secSim · Post by **10secSim** » January 6th, 2007, 3:26 pm

Yeah liten to that guy

JWMotorsports · Post by **JWMotorsports** » January 7th, 2007, 1:00 am

The best thing to do first is perform a compression test on the engine. This will give us an insight as to what condition the rings and valves are in. The key to getting any engine to hold up is to not detinate it.

As long as the compression is good it will hold 12psi as long as you don't detinate...and assuming your using a small to medium turbo. You definately want to use a large intercooler to keep the air as cold as possible, this will increase your detination threshold. Another thing I'd highly recommend is a boost timing retard system. The cheapest would be the MSD 6BTM ignition system...a standalone is the best. Other wise you'll have to retard your timing about 10-15 Degrees at idle (depends on what size turbo you use...larger turbos have lower air temps at the same given pressure as a smaller turbo). Then what happens is the car is slow as balls waiting on boost and when it does spool the timing comes around with it making it just FRY the tires through atleast 1st and 2nd gear...its basically the same effect of spraying a 100HP shot of nitrous.

My recommendations for a cheap reliable motor that will take 300WHP with good tuning:

-ARP Head Studs
-Hone the cyl.
-New piston rings (Beck Arnoly, Sealed Power, Mazda...what ever you want)
-Fel-Pro or Cometic MLS Head Gasket
-Tri Metal Bearings (ACL, Sealed Power)
-Shim the stock oil pump or Mazdaspeed oil pump relief spring around .200"

This was my test engine setup that I mentioned in the last reply.

jaydog5678 · Post by **jaydog5678** » January 7th, 2007, 2:15 pm

The B6 engine can handle whatever the BP can handle. My 94 B6 engine has identical internals to the BP Dohc engine as well as the turbocharged BP-T. I run around 350hp/ 300ftlbs at the crank on my BP with stock internals. Before the upgraded turbo, it was around 215 to the wheels for several yrs.

I would have to agree that a compression test and leak down test would be a good idea before doing anything. You can get an idea of the condition of the engine at that point. If the numbers are a little low, then start thinking about parts that you will need. JW mentioned all of them. Bearings, gaskets, rings, and studs are preffered over using bolts for several reasons. I would save your money from buying aftermarket rods and pistons if the hp goal is low. These engines are strong from the factory.

kami_no_michi · Post by **kami_no_michi** » January 8th, 2007, 11:19 am

well the problem is im hardly a mechanic so anything being done will have to go through a garage. i havent bought the turbo or manifold yet. but im having my car in the garage tomorrow for a new fanbelt so i will ask them if they will perform a compression test at the same time. i will send a reply with the results. as far the parts u listed. No one mentioned anything about using a standalone ecu to manage the new turbo installed. i hear haleteck ex6 is apparently the best ecu out there for my car so i was thinking of buying that then taking it to a dyno shop and have everything set up by them. also could u guys give me some links as to where to get these top end parts england really sucks for mazda performace parts. too many vauxhall corsas, citreon saxos. and ford fiestas in england all with shitty engines

why dont the english acknowledge that jap cars dominate european cars

kami_no_michi · Post by **kami_no_michi** » January 17th, 2007, 12:02 pm

bump: thought i would update my situation i jsut got my car back from the garage the compression test results was 150psi accross all cylinders.

bad news is he thinks the reason i might be burning oil is my valve stem seals

Franko · Post by **Franko** » January 17th, 2007, 2:09 pm

Baah, valve stem oil seals.. Nothing to changing those. They arent a big deal.

Anyway.. If youre ever worried about running boost on a stock engine consider this. The load on youre connecting rod on the power stroke is signifigantly less than it is when your piston is at bottom dead center on the compression stroke. When your piston drives downward with the power stroke there is a compressing load on the rod and a small bit of tensile load (pulling load) which ends up in less overall load on the rod. However, once your piston approaches bottom dead center and comes to a complete stop for that split second and then is accelerated upward again at a mind blowing speed on the compression stroke the load on your rod is all compressive so its stress is much more than that of the power stroke. So when you boost the car, Yes you are increasing the load on the rods but its nothing more than what they are allready designed to take.

Let me tell you though, The key to a reliable turbo car is the tuning. If you keep detonation away you can make very nice power on that motor. Detonate even for one second at 6000 rpm and there has allready been 100 revolutions with 50 uncontrolled explosions of which it reaches over 10,000 degrees at the center of and pressures far beyond what even a good set of rods could take. Given thats a worst case scenario. Just make sure you get something good for tuning or you might be in for a rebuild.

But then again... What do I know?

94blaze1.6 · Post by **94blaze1.6** » January 17th, 2007, 2:12 pm

LOL that is well said franko! wait or is it Corky? I just finished the book for the 3rd time and your comment sounded awfully familiar...

94blaze1.6 · Post by **94blaze1.6** » January 17th, 2007, 2:13 pm

Not to highjack or anything but a quic qestion for franko: Is the bpts turbo water cooled (the stock unit)? thanks man

94blaze1.6 · Post by **94blaze1.6** » January 17th, 2007, 2:17 pm

double post edited