Major engine problems, need some advice

[mr_rotary]

Wasn't this the car that was advertised on E-Bay for a while along with that other MX-5 and the bird?

[sabretooth]

Sounds like a bung lifter to me. Time will tell!

[enzosRus]

Yeah, it was on ebay few months ago with that other mx5 with the helequine paint job, ive had it for about three months. Im hoping its just a lifter lol, anyway ive spoken to my mechanic, he seems confident he can do it well and his a mobile mechanic so he'll come past whenever he has time and work on it, ill be able to give him a hand too, this way i wont have to tow the car across melbourne lol. Hes gonna start monday morning so hopefully the car will be back on the road soon. Once its going again, im going to get an omp corisca steering wheel so if anyone is interested in a woodgrain nardi wheel, let me know and we can work something out once ive change it. If theres any mx5 cruises in the next few weeks, id like to get along to that. Thanks again for your feedback, ill keep u all posted on how its looking once weve started pulling it apart.

[enzosRus]

Well the motors been pulled apart and it doesnt look to good. After much decission making, ive decided im going to do a complete engine rebuild. What had happened was two little balls of metal came lose 'somewhere' and made a bit of a mess of cylinders two and three. The loud ticking sound was a piece of metal jamming under the valve. The valves are loose, theres lots of scratching and marking, and if i were to just reco the head and put it back on, it could happen again as we dont know exactly where the metal has come from, theres no where obvious. Also, we dont know how well the bottom end will cope with the higher compression of once the heads shaved. It may run alright, or it may blow smoke.

Ive decided im going to order a specialist performance rebuild kit from america. It comes with everything needed and will run perfect with the hks cam kit in the car. Below is a list of what is included in the kit. As i am under the new p plate laws, i cant drive a turbo car so ive spoken to the place and they will include 11.0:1 pistons instead of the lower compression stated below for the 1.6 motor. My plan will be to get a pretty whicked N/A set up as im already running extractors and full exhaust system, and i have an apexi intake and apexi air fuel controller (safc) which will give me some tuneability for now. The head will be ported, shaved and fitted with oversize valves. Eventually i will get an individual throttle body set up, bigger injectors and new ecu. Im also looking at upgrading the clutch while the motor is done, so any recommendations would be apprectiated. Below is the kit and a friend of mine used to work for an engine rebuilding company and shes still good friends with the boss. After speaking to him he was more then happy to do the job himself in a few weeks for a quarter of what i was quoted at a few other places. Hes been doing it for years, he has all his own machining tools and my friend said he is the most obsessive mechanic she has ever worked for, which is always good to hear when it comes to engine building.

·Complete Gasket Set
.Belfab Pro H Beam Rods
·Supertech Forged Pistons
1.6... (78.5mm, 79.00mm 8.6:1 comp ratio)
·Performance Rings
·Performance Wrist Pins
·Supertech Intake Valves (Black Nitrided)
·Supertech Exhaust Valves (Black Nitrided)
(Standard or Oversize)
·Supertech Valve Spring Kit
(Springs, Titanium Retainer, and Seats)
. HP Rods, Mains and Thurst Bearings

Let me know what you guys think. Sorry i havent been posting, ive been very indecisive on what to do as i couldve just put the reco'd head back on and hoped for the best, rebuild the motor to relativley std specs, gone with this kit or i even made some enquires about doing a rotary conversion lol. But I want this car to remain completely street legal, thats why i have the ride height set at 105mm. Im really interested in everyones opinions as i will be looking at starting in two weeks time. I really have appreciated everyones advice thus far. Hopefully the australian dollar will become stronger so when it comes time to order parts, it wont be 'as' expensive lol

[Blue94t]

Sounds like a great little package. The only thing I would question is the 11:1 compression ratio. It is pretty high and will require 98 octane fuel to run right. You would have to be careful to get good fuel and I would recommend carrying a bottle of octane booster at all times in case you can't get 98.
Personally through trial and error I found 10.5:1 was about the limit for pump 98 octane fuel but that was with a Nissan L series engine not a B6.
The B6 combustion chamber/squish design may cope better with the higher comp.

As for the clutch, the motor won't be overly torquey, at least not compared to a turbo setup so a heavy duty exedy clutch should do the job fine. I would be looking at a light flywheel to take advantage of the revvy nature of a worked B6, so it may be worth going to an aftermarket BP clutch and flywheel assembly. I had a Fidanza flywheel on my BP and it transformed the car.

As far as maintaining legality is concerned, you will have trouble with any aftermarket ecu set up, even the safc is illegal as it allows you to change the mixtures which affects epa/adr regulations. As such quad throttle bodies are quite hard to make legal.

Should be an awesome little screamer, you will have to take me for a drive when it is done. Then I can take you for a drive in a 2L turbo MX5 so you can see the difference.
Good luck with it and keep us posted with the results.
Jake

[Boyracer]

Don't waste your time doing a 1.6...better to put in a 1.8 and stick a turbo on it...or just get a second hand 1.6 and turbo that...will cost you a lot less and have heaps more power....

[enzosRus]

Yeah i was looking and getting an exedy heavy duty clutch and lightened flywheel assembly. There not too expensive on ebay. Ive also been told that i will need to run 98, which ive always run anyway but ill talk to the engine builder about whether i should go 11.0:1 or 10.0:1 ratio, i can get either. About the turbo set up, i would love to turbo the car but as a p plater i cant drive a turbo car, and whenever i or my friends have been pulled over, the first thing they look for is an intercooler behind the front bumper and then either a turbo or supercharger in the engine bay. It will never have the power of a turbo set up, but it will definatley have some go and it will be a pretty strong reliable set up for the occasional track day. And for the price im getting it all done for, it really isnt much more expensive then a turbo setup and new motor anyway. If the australian dollar wasnt so low atm, it would probably cost the same as a turbo set up. And it will scream lol would love to go for a drive in a 2L turbo mx and i will definatly be taking it on the next mx cruise as soon as its done, hopefully over the next month or so.

[Rotary]

Well the motors been pulled apart and it doesnt look to good. After much decission making, ive decided im going to do a complete engine rebuild. What had happened was two little balls of metal came lose 'somewhere' and made a bit of a mess of cylinders two and three. The loud ticking sound was a piece of metal jamming under the valve. The valves are loose, theres lots of scratching and marking, and if i were to just reco the head and put it back on, it could happen again as we dont know exactly where the metal has come from, theres no where obvious. Also, we dont know how well the bottom end will cope with the higher compression of once the heads shaved. It may run alright, or it may blow smoke.

Where is the scratchings or markings are they on the cylinder walls or pistons? if so then a complete build is in order, if no then you don't need to rebuild a motor to cope with a head shave.

If rebuild is required then consider this, most of the parts you have listed with the exeption of larger valves and 11 to 1 Comp Pistons, will have no power gain benefit. they are strengthening mods. larger valves (usually 1mm oversized) and the pistons will only have small performance gains, unless you match them to some wild CAMS.
porting is decent and together with valves may give you 5-10% improvement above 5k rpm, and pistons may give you around 5% throughout the whole rev range, but all up your talking about 10% to 15% for how much money. im Guessing it would leave you dissapointed and as Boyracer said an 1800 would give you more for your dough, even non-turbo.

what do you rev it to now, have you removed the revlimmiter? the stock internals seem to be good until 8k rpm, so unless you plan on reving it to 9-10k, strength mods arn't that necessary, and with your HKS mild cam the gains above 8k won't be much better than just selecting the next gear and riding the torque band.

The head port and polish will prob give you the most gains, and while its off if you put the valves in then, you'll have most of the power without the additional cost and still rev to a usefull 8k.

its up to you to work out if the cost is worth the minimal 10% or so power gains, and I do like where your headed with the build , its just missing a few key ingredients to make it a powerful engine.
The main thing its missing that would be the first thing I ordered if I planned this build, are some high lift, high duration wild cams. .
who cares if it idles lumpy and at 1800rpm, your gains will be in the region of 30-40% with power.
Downside- it will end up costing way more than turbo to make it work right

[enzosRus]

The scratching and markings are on both the tops of the pistons and on the cylinder walls and the bottom end just looks old and worn. Thats why my mechanic believes it will blow smoke if we just recondition the head. The cross markings are warn away on the cylinder walls. The cams i already have are high lift, high duration wild cams and the thing has the lumpiest idle ever lol so im going to keep them. Thats one of the reasons i got the car, because the cam kit it had which is supposed to be pretty expensive. Also, once the motor is run in i am planning on removing the rev limiter and i use the car for drifting so i want a strong reliable set up. The cars running tein coilovers and a cusco lsd so once i get the engine built strong with a decent clutch, it should be a decent occaisonal track car, even naturally aspirated. The reason i am also going with this set up also is because through this friend of mine, i can get this set up for the same price that my mechanic quoted me for just a normal rebuild through a company called reflex which ive heard arnt the best anyway.

[Rotary]

Rebuilds the best way to go then with that damage
Are you running the stock computer now or a piggyback which still relies on the original rev limmiter? if so its pretty easy to remove the stock limmiter.
if no piggyback do you have a way to adjust the fuel mixtures? like jaycar DFA or similar

I guess the word wild can be missleading or open to interpretation, what I should have said is Non-Streetable Race Cam or even a few Streetable(barely) Race Cams have good HP potential (40%+). Some cam manufacturers will use stages to describe their Cams, in which case Stage 4 or 5 would produce good HP and benefit from being reved up to 9-10k rpm

[enzosRus]

Im running an apexi safc so i have some tuneablity for now but some time next year i will be upgrading to a completely stand alone aftermarket ecu set up. To get the best out of a naturally aspirated set up, i will need to get rid of the airflow meter and run a new computer. I will decide which way to go after some more research later down the track.

As for the cams in the car now, im not exactly sure what stage cams they are now, but i can tell u i have always had major stalling problems from the lumpiness of the idle and most people who drive the car cant help constantly stalling the car. I have gotten used to ridding the accelerator while braking and idling and easing the revs down when coming to a stop. Once the engine builders got the car, ill find out what stage cams they are, and if there are considerable gains to be had with better cams, i can always upgrade later on with the strength of the new motor to back it up.

[Rotary]

Good to see a nice N/A build, building it tough is the sensible way to go about especially if putting it through some hard yards.
Lumpiness can also be just a state of tune or cam setup, but once your mechanic sticks a dial gauge on it, you will know what its doing at every degree.
in the end it may be enough for what you use it for, and cams are the easiest parts to swap if you decide to do it later.

Did you get a chance to Dyno the setup before it blew? nice to see what RPM you pick up torque also make a great resource for others planning on working there B6's
Good luck with it, and post up a dyno once its done.
Matt.

[enzosRus]

Some new info on the progress of my build. Well i was going to start next week and order the parts and everything, but when i told my mum she flipped it cos i told her how much it would cost and she said ive already wasted enough money on the car etc,etc,etc. Im sure most of you have heard this from either a spouse or family member, i guess they care but they just dont get it which is understandable, it can be a considerable amout of money. Anyway, so she called up my uncle who was a mechanic and who is a car nut constantly upgrading, swapping motors etc in most of his 7 cars, lol. He recommended i put a second hand motor in for now to keep her happy and show her its running, and then work on the motor bit by bit. So at the moment, im looking for a temporary motor which he is going to put in, and while my current motor is out, i will send it away to have all the machining done. In the next month i will plan on ordering the parts. Also, i have the the head sitting in my garage, and on the cam reads HKS and theres a number that reads 264. I had a look on the HKS website and it says the cam duration is 264 and the cam lift is 9.5mm. It seems to be the biggest cam on there website out of the two they make. Would this be a good basis for some decent N/A power figures? From what ive seen, it seems to be possibly a stage 3 cam but im just guessing.

[enzosRus]

Picked up a nice clean b6 motor today for $650 delivered with full 3 month warranty from Jap Auto Parts in Sunshine. Looks decent, the jap tag on the top says round 50,000 kms but i dunno how trust worthy it is. The motor looks neat though, the valve train looks clean from what i could see with a torch and everything seems to be in order. The guy said if anything is wrong with the motor, not only will they replace it but they will cover all labour and towing involved which is good. Hopefully by some time next week, we'll have the car running and ill come down to one of the mx5 cruises. I might even get the car dynod with the std b6 motor (will be running extractors, exhaust and cold air intake still) to make a comparison once the original motor is rebuilt.

[93_Clubman]

WTG - line of least resistance & it gives you some time & space in which to plan