Unfortunately my engine seems to have gone bang at a rolling road session. The tuning guy was revving the engine and he detected detonation. Reduced the boost by 0.1bar and still no high revs. Then big puff of dark smoke from the n/s exhaust and would not rev past 4000rpm. Jeff took out the plugs and 5 of them had no top metal bar. New plugs in and the engine was idling really lumpy and ticking badly too. I have taken the car to get the compression tested but it looks like some damage up top. Assuming the head needs to come off and some work has to happen - what are my options for more performance on the rebuild?

 

------------------

"Polished on drive"

"Dirty at 156mph"

---------------

Z first and anything else is secondary and live life a quarter mile at a time!

John Newcomb (NukeEm)

www.geocities.com/jn300zxtt

Posted from SteamyZs(Steve) post on TT.net:

 

Motor building TT owners....info from my trip to MS and JWT

 

Posted by: SteamyZ(ZtoyZ.NET©) on April 29, 2002 at 9:16 pm

 

This message has been viewed 377 times.

 

Well i had the chance to spend the entire day and most of the night with the folks at JWT Saturday....we were down there doing some fuel tuning on Mark Leaders race car. About mid day Mike Kojima shows up and then Mike Smith (MS Performance-Z 32 engine BUILDER). I got the chance to talk with Mr. Smith for about 30 minutes one on one about "budget" engine building and what i need to do to make my set-up reliable.

Below is some VERY good information for those attacking engine buiulding here soon. Some of it will contradict what has been posted here and may even offend some that have spent their hard earned dollars on stuff they dont need. So be it. This is from THE MAN himself.

 

BTW the folks at JWT are SO impressively humble, nice, genuin and GENIOUS LEVEL intelligant....at one point Greg Dupree, Jim Wolfe, Clark Steppler, Mike Smith and Mike Kojima were in one room talking Z's....i cant not convey what was said...but i tell you to quote Mark "the combined experiance and knowledge these guys have is staggering" Well said. This was a REAL treat indeed.

 

OK info for ya....

 

This will be somewhat randon so not to take up too much space....I got enough info to write a book

 

Pistons:

ONE of every 5 blocks once sonic tested will test NEGATIVE for anything bigger than a 87.5 MM piston. The OEM factoiry castings are hit and miss and may crack if bored bigger...unless you end up with a block that can withstand it. To machine a Z32 block properly...or any block for the type HP i want to make...you want to use "deck plates" which are touqued to the block to simulate the heads being in place. This actually warps the cylnders into their shape before machining the bore. VERY VERY important....or you can end up with egg shaped bored that dont hold up very well over time.

 

There's 2 types of pistons to consider....low or high silicone content. Low meaning the pistin will hold about 2000 hp BUT will expand more (2-3 thousands) once warmed...cuasing oil leakage (burn a bit of oil cuasing you to have to fill it allot). The good thing...they are VERY VERY strong. Im going with the Arias pistons. Once coated with the SWAIN coating... the tolerances should be set to 1.5 thousands. Also make sure to use the Swain PC9 skirt coating as it wears less than the other type they sell.

 

Main Bearing:

Use the Z31 main bearing part # 12111-o2P00...they are made of a stronger material than our Z32

 

Use aftermarket rods...th OEM material is heavy....and when combined with higher than OEM revs....they can stress bend. Shot peening and polishing will not help enough too to the material they are made of. It should be noted...rod failure is VERY rare...but for the money....its worth it in Mikes opinion.

 

Machining:

 

Make sure to use deck plates....also dont machine the stock crank jounals (which should be used BTW....afternarket cranks are $$$ and OEM stands up to the stress. You want to polish and de-burr the surface. If your going to spend your money Cryo-treating anything...start with the crack. Also want to mill the main bearing section (wrong lingo i think) witht he main caps in place and touqued to ensure the crang rotates purfectly (make sense?)

 

OK...now heres what NOT to spend your money doing

 

DONT port the plenum OR the throttle bodied....the ONLY gain is at low throttle position...makes it a bit more crips BUT NOT worth the money...at WOT there is no gain! Match porting the lower intake to the head can be DIY and is pretty cheap and is worth it. Do that if you can.

 

DONT buy aftermarket cams if your on a budget....i was told to use OEM 5SPD cams with stiffer valve springs....they will take a 7500 run. My turbo housings will allow me to flow power to right about that point.

 

DONT spend your money on ARP head studs...BUT instead use ARP main studs (rod bearing)....i take it this must be more important due to the stress. OEM head studs are AWESOME.

 

DONT use Mettle head gaskets as OEM are actually LESS likely to leak. He said ALL metal head gaskets (which are 2 peice) will leak at some point...usually around 80kmi. You can use a 88 mm pistom with the OEM head gasket....which is still a nice over-bore.

 

OK heres some other tips i learned...they are pretty public but ill say it anyway....also this is in Mike Kojima's SCC article.

 

Epoxy fill the block for added strenghth....right around the CYLND. Im meeting with Mike again to learn exactly HOW...many of you may know.

 

Go though the block with an extended dremel and get at the oil and water passages....as they are HORRILBE and filled with flash material. Again...very "known"

 

 

Well thats about it....again im sure some you may want to debate some of this...which is cool. Have fun :-) Hope this helps someone...i know it did me. Sorry for my bad typing and bad spelling.

 

I think Nico and Steve E may have more info as they have both upgraded internals I think.

Cheers,

 

------------------

 

Trev

1990 300ZX TT 2+2(import)

http://www.300zx.co.uk/rides/trey/

Where was this and hell that should not have happened on a dyno. Thats what they are for to prevent this happening?

so please tell us where so we know where not to go lol.

 

this is shit for you , i honestly can say i know how it feels.

Now it all depends on how much your prepared to spend ect.

once you know the exact damage, you can then decide on what is needed/wanted ect.

 

 

------------------

While my TURBO'S are Spooling V8'S are Drooling

Sounds like a fair amount of potential damage that Warren is correct though - this shouldn't happen on the dyno...

 

Bit of a difficult question to answer until more is known about whats popped etc. How far do you want to go? Do you still want a driveable car etc? Forged pistons and rods, race cams, solid lifters are all possible options... Like I say how driveable do you want the car to be???

 

Also if it has gone then I really would not run it until you are sure there's no chunks of valve trying to pass through the turbos - this will kill them

 

CheerZ,

 

Andy

 

R.I.P your engine dude ! sorry and all that but i would expect serious damage to both the Heads and the cylinders - Bottom end should be ok.

 

As far as upgrading is concerned - I would seriously look at your Air / Fuel setup first - You are obviously not running efficient boost to make high HP this is why you burnt the plugs !

 

Forged pistons are a obvious winner - altho as you have found out there are a lot of other things that can fail appart from the pistons if your running too hot ! If your heards need a lot of work - a Angled valve job is nice and so are JUN valve springs ! make sure you dont get some spud to do the work tho.

 

Also running 1.35 bar on your setup was asking for troble - Im sure i must have adviced you before not to run that much without additional cooling or more efficient turbos you will blow any engine at that pressure !

 

Good luck with the rebuild work - but i would take it easier on your next engine ! Tuning these beasties is a very dangerous game ! Oh yeah and i wouldn't go to that rolling road again !

 

 

 

 

------------------

Z ya

 

Nico91TT

 

 

God is coming ...and he dont have stock turbos . . .

Rolling road was in Tamworth, Sid's Tuning Shop, good gear but not very confident tuner. The engine has JWT sports 500 turbos, 555 injectors and a JWT ECU and have been running great - no pinking/detonation. I think I may have picked up some crap fuel when I was running short recently and dropped the boost to low 0.5bar and forgot to fill up on Optimax for the rolling road session and the tank may have gone too low and dragged up some crap. On first run heard pinking so I reduced the boost to 1.1bar and then secind run bang, lumpy and wouldnt rev past 4k rpm. Nissan done a compression test and no compression on cyl 6, 150psi on cyl 1, and the rest are between 90/115 psi. Leakage test and then heads coming off for a look see later so I expect no better news today.

 

I am guessing that getting a secondhand engine and making one good one from the two may be the cheapest option. But thinking of doing that and selling it for a TVR or a Viper as they seem to be more reliable!

 

Mike Feeney/MJPAutos suggests uprating the camshafts, valve springs and lifters if the heads have to come off. I don't want to go any further as I want to still be able to use the car every day and then drag and trackday it occassionally too.

 

Damn just when I was happy with it. I really thought taking it to a rolling road for a tuner to check it would have been a good idea!

 

Does nobody know anything about these cars other than owners?

 

------------------

"Polished on drive"

"Dirty at 156mph"

---------------

Z first and anything else is secondary and live life a quarter mile at a time!

John Newcomb (NukeEm)

www.geocities.com/jn300zxtt

.

 

[This message has been edited by marczxt (edited 24-06-2002).]

dont mean to scare you but detonation can cause the engine to go bang like in these pics of this 300 engine VG30DETT

and

and

and

and

and

and

 

The rolling road session probably caused the damage as they can can't flow enough air with those fans to ran high boost safely.

I feel for you John bad bloody luck.

 

[This message has been edited by marczxt (edited 24-06-2002).]

Originally posted by jvnewcomb1961:

Rolling road was in Tamworth, Sid's Tuning Shop, good gear but not very confident tuner. The engine has JWT sports 500 turbos, 555 injectors and a JWT ECU and

 

Sorry again John dont mean to kick you while your down but I wouldn't risk 20psi on that setup ! I would seriously not recommend anyone run over 17psi even with bigger injectors and turbos for a prolonged time in this country ! Additional Intercooling would have helped as the sport 500 turbos will not push that much air with a great deal more efficenct than Stock turbos

 

 

I am guessing that getting a secondhand engine and making one good one from the two may be the cheapest option. But thinking of doing that and selling it for a TVR or a Viper as they seem to be more reliable!

 

Not a bad idea - if tuned correctly these cars are ok - altho it takes a helluva a lot of money and know how to tune them to not blow up ! a Good TVR or Viper will make more reliable HP for a lot less Cost - ASSUMING you pay the same money for the car ?!?!

 

Mike Feeney/MJPAutos suggests uprating the camshafts, valve springs and lifters if the heads have to come off. I don't want to go any further as I want to still be able to use the car every day and then drag and trackday it occassionally too.

 

Hmmm camshafts - Yeah a way to go - you genearlly loose soo much bottom end with the aftermarket camshafts out their it aint worth it unless you want a drag car ! waste os money in this country IMO. Lifter - why in gods ass would you want to upgrade those ?!?! Springs - Yes a good idea

 

 

Does nobody know anything about these cars other than owners?

 

 

It is looing increasingly like NO is the answer to that question - I seriously recommned against people that dont have a lot of money , knowhow and time or on there side going above stage 3 with their cars in this country !!

 

Good luck with the rebuild and let us know what they reckon has blown !

 

 

------------------

Z ya

 

Nico91TT

 

 

God is coming ...and he dont have stock turbos . . .

Actually a good point was made by Tonycarter, 300z owner there on saturday, that just occurred to me the fans were sucking not blowing! BASTARD!!!! F*****. I swear I will never go to another rolling road ever again! Fu****g useless tossers! Nice Posrche 928 S4 and a red Viper for sale -I'm bloody tempted!

 

[This message has been edited by jvnewcomb1961 (edited 24-06-2002).]

Originally posted by jvnewcomb1961:

Actually a good point was made by Tony that just occurred to me the fans were sucking not blowing!

 

Who is Tony??

Yeah Rolling Road sessions can be dangerous to Engines cos of the air flow problems also they show up a weakness in an engine quite quickly, my mate blew both crank case oil seals straight after a rolling road session

 

I kinda feel a little defensive now. The 1.35 bar setting was used only on the EVC scramble mode and ran only for 13 seconds at a time, eg. for drag runs. During the last 2 months of running it that way neither I nor anyone else hearing the car rev hard ever heard any pinking from it. On normal day to day I would use the high setting on the EVC which was 1.2bar/17.4psi. Now I am not a stupid person and I understand how easy it is to damage an engine with detonation which is why before I set the EVC up I asked the question what have people set theirs to, which I was told by many people set their EVC to, and not just here in the UK but also contacted owners in the US and telephoned JWT and Stillen. I was told numerous times that setting the EVC 1.1/1,2 would be fine considering my setup and fuel I was running. Now in hindsight I should have just shot myself for being a prat rather spend money on a car I loved.

 

The trouble with upgrading your car is that it is all so much guess work. Guess what bits are right to fit, guess whether the tuner actually has a clue what he is doing, guess what settings to use and guess which garage to go to for the work. Of course in hindsight everyone can tell you what you did wrong.

 

Anyone who buys a 300TT as a performance car rather than just a "get me about in a class piece of bodywork" must be a certifiable f*****g lunatic. Everything you do to the 300 will make it break faster than before, everytime you fill it with petrol you get closer to the next breakdown and everytime it goes near a garage the thing it goes in for fixing comes out the same and something else has gone wrong with it whilst it was in there. Where is the fun in owning a car that spends so much time off the road?

 

Recently I was speaking with a group of performance car owners (TVR/Viper/Porsche/Cosworth, etc) and was getting a bit of light joking thrown at me after I said what car I drove. I was angry and very defensive at the lighthearted abuse the 300TT was getting and argued with them all about the great things the car brings when driving it. Now I would just agree with them, it is a piece of badly designed, badly engineered, badly serviced and beautiful looking but expensive piece of crap! And if I am stupid enough to get it repaired rather then towed to a scrap yard cutting my extensive losses then I can honestly say that I am one of the most stupid people on the planet.

Yours some f*****g idiot.

 

------------------

"Polished on drive"

"Dirty at 156mph"

---------------

Z first and anything else is secondary and live life a quarter mile at a time!

John Newcomb (NukeEm)

www.geocities.com/jn300zxtt

M8, cosworth and TVR owners suffer the same stuff as us. A brand new TVR owner drove his car out of the showroom and a few miles down the road broke down, he phones the garage where he bought it from, to be told on the phone "Welcome to the TVR experiance!"

High HP Cosworth engines need to be rebuilt every few thousand miles. Really the most reliable performance car would have to be a Porsche 911. So if u got the dosh buy a newish one of these.

 

[This message has been edited by marczxt (edited 24-06-2002).]

No way, even though with all the money I have spent on the 300zx I could afford a new boxster I wouldn't be seen dead in a Porsche! I would prefer to be recognised when parked on the back of an AA recovery wagon, as usual.

 

[This message has been edited by jvnewcomb1961 (edited 24-06-2002).]

well first of fuelling in the UK and The states are two different things, secondly it takes less than 13 seconds of detting to make a right mess of your engine. My car was detting yet it was not very audible.

You simply ran to much boost.

 

 

Again the place you had it dynoed are twats sorry but they knew obviously not a great deal about what they were doing.

 

[This message has been edited by 300z (edited 24-06-2002).]

I agree with Warren they should have warned you of running high boost in this warm weather, rolling road on warm days big bad idea espcially on turbo cars.

Were you doing just a power run to see what power you were running or were they tuning your car?

I was there as a rolling road/dynomometer first timer. I wanted the car "tuned", whatever that means these days, and assumed that a tuner would know everything about every type of performance car and would be kind to it, rather than revs the crap out of it blowing it up. I was also interested to find out what power it was putting out as everyone and their dog seems to ask me that question and I wanted an answer.

 

Of course the answer is easy now, 22bhp if I'm lucky at it runs at all. Ah well you live and learn. If I ever get it back I will immediately take everyones advice, that probably means setting it up 14 different ways and taking it to SE Nissan for 4/5 months of treatment.

 

------------------

"Before it blew up"

"Now driving a Celica - great NOT!"

---------------

Z first and anything else is secondary and live life a quarter mile at a time!

John Newcomb (NukeEm)

www.geocities.com/jn300zxtt

What bunch of muppets, if they were suppossed to be tuning the car I think they might be liable. They should have wound the boost down to its lowest setting first if they were tuning. Did they check your fluid levels first before the run. If they didn't you might have a case against them for not taking necessary precautions.

john,

it sounds to me like you maybe able to have them for it. the car was in their hands when it went bang. I have just had nelson maindellas pay 3k towards a rebuild, after they made a mess of changing my cambelt. you have nothing to loose.

I totally agree with wild turkey. I don't know anything about r/roads (it seems they didn't either) but after reading what's been said through this post, it seems that someone with a bit of knowledge would have worked from a lower boost up. You've got nothing to lose with complaining.

 

Good luck,

 

Vijay

Originally posted by marczxt:

Who is Tony??

Yeah Rolling Road sessions can be dangerous to Engines cos of the air flow problems also they show up a weakness in an engine quite quickly, my mate blew both crank case oil seals straight after a rolling road session

 

Indeed I did mate. If you remember correctly the guy who dyno'ed our cars stated quite clearly the following:

 

A turbo car should be tuned on the road with a wide band o2.

 

Rolling roads do not give accurate power figures.

 

Rolling roads put a much higher mechanical strain on a car then normal driving ever will.

 

I won't take responsibility if your car breaks.

 

===========

 

My car blew a front crank oil seal after one dyno run. If there is a weak point in your car a dyno will probably find it.

 

I for one will never put my car on a dyno again.

 

 

John, bad news about your engine mate

 

BUT, over the past few years, I have seen quite a few TVR's on the hard shoulder. Not much more reliability than Zeds.

 

If the cooling fan was blowing backwards, I can't believe how negligent the R/R people were. Also, as GavinL said, they may take no responsibilty for your engine giong pop.

 

I have seen a carbon dioxide fire extinguisher being used on intercoolers before a run to cool them down, maybe this would help on hot days??

 

 

Robert.

 

 

P.S. Don't beat yourself up about it. It can get fixed. At worst, engine swap and put all your performance bits on new lump.

------------------

 

I only use the brakes so I can accelerate all over again.

 

 

[This message has been edited by dunk300zxtt (edited 24-06-2002).]

Well called in to see the engine as it was taken out yestyerday. Loads of oil from turbo and other places. Heads off today but no 1 piston may be holed and I suppose that means replacing all of them, and more?

 

Option 1. rebuild existing engine. (forged pistons this time?

Option 2. buy s/hand engine.

Option 3. buy recon engine.

Option 4. buy new engine.

 

If I decide to go for rebuilding my engine do I upgrade to better internals or stick with Nissan OE? Do I get Nissan to do it so I get a guarantee/warranty or do I take the engine somewhere else to get it done?

 

Nico, you seem to be the most knowledgable persion round here, if not on this continent, what do you suggest?

 

Oh and I intend to immediately and disappointingly reduce the boost settings on the EVC when I get the car back:

Low - 0.5bar, High - 1.0bar, Scramble - 1.15bar for 20 seconds and Warning - 1.2bar.

 

I'm now gathering opinions ready for decision day tomorrow. Wish I was a little technical.

 

 

------------------

"Before it blew up"

"Now driving a Celica - great NOT!"

---------------

Z first and anything else is secondary and live life a quarter mile at a time!

John Newcomb (NukeEm)

www.geocities.com/jn300zxtt

OK the heads came off and some damage to both sides as you can see from the pics below:

 

The rebuild requires:

Only 1 piston was damaged but will be replacing all 6 pistons @73.70 each.

A piston ring set @132.00.

One set of crank bearings @32.60.

A full set big end bearings @19.20

An engine gasket set @232.00.

12 inlet valves @13.70each.

12 exhaust valves @27.40each

Only 1 hydraulic lifter damaged but considering replacing all 24 @46.70each.

New oil pump as it is 11 years old @151.

 

Whilst this is being done do I pay for forged pistons instead of Nissan OE and uprated valve springs or stay with Nissan OE?

 

It is far less damage than I expected. So a little less unhappy!

Most importantly no damage to the new turbos! Hooray and thank god!

Yes get forged pistons!

£132 for piston ring set sounds far too much.

my set of Hasting Rings (top quality) for my 200sx we £33 + VAT.

 

If you get a forged piston set they shouldcome with new rings, gudgeon pins and pin clips.

 

Deffo go with the oil pump, and perhaps get some thicker Greddy metal HG's, and some decent cold plugs to help avoid the same demise again.

 

RE valves, someone on our board just got some inlet ones for £9.50 each, might be worth trying where he got his from.

 

"...I got them from Stockport Engine Centre who got them from GTI in London I think. I'll tell you all I can find out when I pick them up tomorrow.

 

Nissan want £17.50+vat each, whereas these were £9.50+vat, which is about normal(ish)..."