Hi everyone, I ran with 15psi last year and blew my piston apart, next year I am hoping to get it back upto 15psi. But not before making sure the car can take it safely. What exactly should I be doing and getting fitted? Sorry guys I admit I am no mechanic and have very limited knowledge of engines...

 

Thanks for the help :-)

 

Dan

you will need exhaust, good filter, better intercoolers. injectors and a remap :wink:

not to mention uprated tubs as stock become inefficient after 14psi, then forged bottom end to cope with the power

Eagle rods sounds like a good idea going above 14psi, bigger turbos or at least hybrids. Bigger injectors, uprated inter-cooler, better brakes to help stop the thing.

internals should be alright if everything is healthy. i doubt he would get over 400hp with these mods

internals should be alright if everything is healthy. i doubt he would get over 400hp with these mods

 

If i went above 14psi, id definitely consider getting eagle rods, even a Nissan mechanic i spoke too who was trained on the 300zx said that's the weakest part of the engine.

 

 

The damage from the last time, 2 conrods failed on my 300zx lol

now that pic looks familiar!!!

 

 

eagle rod...

 

14 psi isnt even 1 bar, Ive been running that for the past 4 year. not sure what i am at now think 1.1 or 1.2 bar. Like i said bepends on the condition of the engien

 

Think stock tubs run out at 16/17 psi injectors 15/16 psi

now that pic looks familiar!!!

 

 

eagle rod...

 

 

lol mark, its like that scene out of jaws where they are comparing scars

 

Didn't take a photo of the conrods as i couldn't get them out from the side of the block. i cracked the block in 2 locations as well, destroyed half a counter weight and totally mangled that frame that runs around the bottom of the engine that helps hold the crank in place.

Hats of to you Vods and Bullit. If your going to do it, do it properly.

The state of that rod mark.

Im running 14psi on stock internals, its plenty quick enough, but agree it must have something to do with engine condition.

Hmmm interesting, I know obviously the more boost the more stress the engine is under, so to run something like 12 psi is more reastic on stock internals? tbh I thought I would only need to change injectors, decat and remap to run 15psi

Hmmm interesting, I know obviously the more boost the more stress the engine is under, so to run something like 12 psi is more reastic on stock internals? tbh I thought I would only need to change injectors, decat and remap to run 15psi

 

You could, but then the more you up the boost, the more stress as you say, the internals will be under, look at it this way, you have already blown one engine, the pictures of mine were from a N/A with no upgrades, so apart from the odd foot down here or there, not really under any more stress than what it was designed for, yet it still failed. so id definitely uprate the rods if anything.

 

If uprating the rods is going to make my engine last longer then its sure worth it.

 

Just remember though, Marks rod failed on track use.

Erm, im on 18 psi and as far as i know its got stock internals and turbos, bigger injectors JD ecu and lots of fancy exhaust stuff, i hope a disaster isnt imminent

sparky when are you going to pop over to me lol your bloody close enough

Haha, yeah i know, im at uni in leicester aswell. Its just not big enough for me to take up there, im in the renault 5 for the uni run :D

I thought z32s had forged rods as standard .

Ian how the hell did you blow up an NA :lol:

Ian how the hell did you blow up an NA :lol:

 

 

Haven't got the foggiest lol i bought it with a top end tap, and it was just that, sounded like noisy tappets, that must have developed into a bottom end knock when i was driving around Scotland. next thing you know, crunch and bang, and ala end result, 2 broken con rods lol

Haven't got the foggiest lol i bought it with a top end tap, and it was just that, sounded like noisy tappets, that must have developed into a bottom end knock when i was driving around Scotland. next thing you know, crunch and bang, and ala end result, 2 broken con rods lol

 

I've told you to use gears in the past ;) lol I suppose any engine can let go if its been starved of oil or something in a past life! Hell someone I was talking to a few weeks ago had a 57 plate astra, done 40k and had put a rod through the block. 1.6 petrol nothing fancy, the lass was a home carer nurse so didnt give it a hard time. The worst bit was that Vauxhall refused to replace the engine as good will because it was just out of warranty.

 

Anywho back on track, Ive always been advised not to go above 14psi with standard injectors, and that standard turbos cant do more than 15/16 anyawy without just blowing hot air. It all depends how often yo use it I suppose though. If you drive everywhere at full bore than your going to cause more damage than someone like me that might do 1 balls out overtake a week or so and the rest of the time rumble round at 2500rpm off boost.... I like having the power in reserve LOL

If you drive everywhere at full bore than your going to cause more damage than someone like me that might do 1 balls out overtake a week or so and the rest of the time rumble round at 2500rpm off boost.... I like having the power in reserve LOL

 

Thats how i drive chris. Just there when you need it :cool3:

Thats how i drive chris. Just there when you need it :cool3:

 

It is a smug feeling more than anything... LOL I love being overtaken of a roundabout or something, then you get to the motorway and just go howling past awesome.

 

Infact the best one was a few years ago with my old grey LWB (manual at the time). Vectra GSI was next to me coming onto the (private) motorway at blackpool. Two roads onto the slip road. Zed was in 3rd @ 30 mph so hardly in its stride. So we both floored it down the hill and I though to my self. Hell these vectras arnt so bad, make a lot of noise but yeah going okay. Suddenly bababaababbaaba gear change. Realised that the vectra had been in 2nd... LOL so He changed just as mine was getting into its stride. The poor vectra just went backwards!

yeah the gsi are alright. They would pull on a na well mine would but the tt are in another leauge. DOnt think i have raced a single car in my zed :confused1:

i guess the answer is dan

 

make sure your engine is in good health then stick a decent decat/exhaust on it, better filter, perhaps cooler plugs and a remap from john dixon or zedworld then run 14-15 psi and enjoy.

 

going above this is an expensive jump as you will need bigger injectors/turbos/intercoolers but will get you alot more power, there is no middle ground really as one of the above mods without the other will result in no real power increase or a dead engine.

 

technically speaking a boosted engine will put less strain on its rods (up to a certain limit) the highest stress on a rod is in tension at tdc after the exhaust stroke, if there is a turbo pressuring the combustion chamber at this point the stress will be less than on an equivalent N/a engine. obviously wack a load more boost on and you will load the rod higher at another point in its cycle.

 

its dett that will kill an engine, not just by burning through a piston but the sudden shock loading it places on the rods/big ends. by limiting to 14/15psi you should be keeping the engine away from it detting. if its coked up, with bad timing, bad plugs or breathing heavily it may well dett which is the real engine killer.

just been for a drive, mine isnt at 18 psi, its 15, its been running like that for a while, so i guess thats safe

Its not the rods that caused the failures in the pictures,The bearings seized,spun in the rod then welded the crank and rod together,the fact that Marks was an eagle rod proves It can happen to any rod,corrillo etc doesnt matter how good it is.The stock rods are not weak and are forged as previously stated.They will withstand 500hp no problem.im running just under this and use the car in anger regular at 18psi and the bottom end is perfect after 400o miles.

exactly that Jimmer, it was the bearing that disintergrated through excessive heat, caused the big end to "rattle" on the crank, snapped a rod bolt and threw the big end out.....

 

now, where did i put that scavange pump???:whistling: