14 replies to this topic

[Lev]

hello dear All i would need some SOS info on this: - boosted z22se (mine is turbo converted  but possibbly it does not matter if yours is SCd) - wiseco 9.8:1 pistons + eagle conrods z22se head just cracked apart so bought a whole b207l saab lump. but as budget is unfortunately limited i would just swap the saab head over to my z22se with the forged internals...but: -i have about 1.3-1.5 bar boost and z22se as we all know does not cool the piston by sqirting oil under it, so anyone out there using a similar boost on z22se bottom with wiseco+eagle internals whol could provide trustworthy info on how reliable this setup is? will the lack of piston cooling put such heat stress on the wiseco with this amount of boost so eg pistons would dilate so much they would stuck or would lead to exstensive wear thus pretty much they would die or kill some other part in say next few K kilometers/miles? so make it simple: anyone using this kinda specs and for how long? any issues in meantime? thanks ahead Lev

[Nev]

I doubt (am guessing here) that lack of under piston oil jets will be problematic. Remember that the crank case of most engines is completely awash with both liquid oil and oil gases that splash about every where. For example, on the Z20LEH engine, the jets were installed simply to help the mappers improve idle emissions (running more lean), and the jets would allow the pistons to cool under sustained idle periods. HTH.

[speedster]

Some opinion state side

Ok, here's what I learned. I spoke with Bates Engineering today about this at length. He produces many of the smaller internal parts for GM racing. He's got stuff like tool steel oil gerator pumps, timing chain tensioners, improved valve spring kits, very plugged in. I love talking to him. Anyway, every engine he has built (hundreds by the way) have all been off the L61 engine block, and not a single one of them had the oil jets installed. He runs a 1000+ HP drag car without them. Then, I sat down with my guy Bobby at the GM Goodwrench parts counter at the local chevy dealer and looked up the parts. We had to look at LSJ engine parts of course since the oil jets are not a part of the L61. The computer did list the jet assembly, but showed it as a non-available part for ordering. Couldn't even get a suggested retail price on it. The assembly is actually a rail that has all four cylinders on it and it plugs into an oil tap on one end. So I decided not to bother with it. I have the GM build book telling me I don't need it, I've got Bates engineering telling me I don't need it, and it doesn't even seem like I could get it unless I tore it out of a busted up SS engine.

L61 is a Z22SE, in Detroit.

Edited by speedster, 22 February 2015 - 07:30 PM.

[Lev]

ok thats a bit reassuring. some backgound info to see clear why i wonder...:

 

About 2K miles ago the whole z22se bottom internals got changed: brand new oem gm rod bearings, wiseco + eagle forged internal (main crank bearings were ok so left them unreplaced). as my liners looked intact and measured also just oem values no rebore was done, only a slight honing just to make sleeves "shiny" and got the standard sized wiseco pistons (86.0)

 

 

However my oem z22se head craked like a week ago and it came off and revealed there are slight scratch marks on the sleeves...so dunno if scratch marks are due to too much heat stress and pistons dilated too much or what the heck could cause it..

 

so i needed a replacement head and i  managed to get a used full b207L lump (~90K miles, but looks like it has not seen frequent oil changes or it simply got crap oil but nevertheless not too much wear (eg my oem z22se cams came out at ~40K miles and looked like crap compared to this 2nd hand saab lump..though my oil got changed like every 5K miles as per prev owner..)

 

so due to other recent unexpected failures too much money went in this project (well, 3x the anticipated one) and my last issue was the engine would not rev over 6500rpm...that's eventually boiled down to my new garrett gt2560 turbo which spools extra quick but about 6500rpm it chokes itslef as so much exhaust gas coming out it simply cannot pass thru the tiny turbine wheel..so we fitted a valve that would simply open the wastegate at ~6000rpm to bypass the extra stuff.. and it worked, car revved again to 7000 and we measured 330bhp/400Nm....with a busted hose...so after the hose replacement boost popped up like a good 0.3-0.5 bar and that possibly also brought a good 50nhp/50Nm...so as per my tuner car performance was just spot on, small blip on the gas pedal in 3rd gear at ~ 50mph and the car's rear just stepped out aside... but the head gave up with nice long cracks bolting out from the spark plugs area..

 

so now i need a reliable "budget" solution, and obviously best were to simply move the b207 head over to my z22se bottom and deal done, ready to drive again..but my tuner who was not aware the z22se does not have oil jets to cool pistons  - (well, my original conversion from NA to turbo was not done by them so they assumed if this is already turboed possibly such deatils are in place...not sure though why they never asked or read my links with loads of z22se info...they are mainly a bike tuning shop and they put hayabusa engines everywhere, they do turbo convert those as well etc and lately started to manufacture some kit cars (sonic) as well) - scared me off that with this ~1.5 bar boost there ill be such heat accumulating that even the forged wiseco will wear off in a few K miles...

 

so if after all, with the b207 head, boost at 1.5bar, rev limit at 7000rpm, and wiseco+eagle in a oem z22se bottom can cope fine for like a few years (or say 60K miles) without any further issues (i do not really track the car, only spirited road use) and it will nor fail with a big bang killing the whole stuff then i simply just swap the head and in next few years spare up for the full b207 conversion with the z22se crank...or if the b207L with OEM internals can reliably cope with ~350bhp/400Nm i may simply use it as 2l b207 without any further performance mods

 

share your thought on this please as i need to decide which way to goo next morning...ie to start stripping the engines or simply move the b207 over to my just rebuilt z22se bottom..

 

cheers and thanks

Lev

[Lev]

and an after thought: i understand there  were no performance issues on the Bates drag cars...but i would need this engine running not only for 2-3 quartermiles but for at least a few years (100K miles) without additional service bills..only the usuall consumable bits like oil changes were acceptable so please conside this aspect, too.

 

cheers

[fezzasus]

However in contrast to the above views, Mahle believe that you typically pull away 20% of the heat on the piston with under piston oil jets.

[FLD]

Piston oiler jets are great for cooling pistons, especially on cars where emissions are important and they run slightly lean.  Drag cars will run richer so less risk of melted pistons.  However, if your car is running fine then I'd be very surprised if you 'needed' them fitted.  What concerns me more is your liner scratches.  It suggests to me the rings have too small a gap and are / have been very tight in the bore.  Boosted engines require a larger ring gap.

[Lev]

oki so if my pistons are a tad bit tight then possibly oil squirt were good to have (maybe that extra heat dissipation were enough not to get the pistons "over-dilate") but maybe even the oil squirt may not guarantee this. what i do not really understand if wiseco makes standard oem size pistons for the l61/z22se how come that the clearance is not ok on their low comp pistons which are certainly for boosted applications...

 

but still the question remains: anyone out there with this sort of z22se bottom end , standard size wiseco 8.9:1 low comp pistons running on say 1.3 bar boost that could share their experience? for how long they run like this setup and any issues?

 

cheers

[FLD]

It's not the pistons that are too tight, its the ring gap thats too small.  When the rings expand they close up that gap.  The hotter the engine, the more they expand so the bigger the gap required.  It's down to the engine builder to spec the gaps so you might want to check what gap was put on the rings.  They aren't gapped from the factory.

[Lev]

well, if the wiseco not standard size but still no oil squirt i am still interested in what experiences user have with them on that 1+ bar boost over the long run

[speedster]

What running temperatures are you getting. Are they higher than normal. Also what oil and grade are you using.

[Lev]

temp is normal if you refer to the coolant temp. my fan is set to kick in if coolant temp reaches 85C...only happened even on hot summer day if i was sitting in traffic and hardly moving. as i do not have an oil temp gauge cannot tell about that.

 

oil is Motul 8100 X-cess 5w40

[Lev]

ring gap should be ok but as the block now comes apart as I decided to move all stuff over to the b207 block we will doublechek that too

[vocky]

Some opinion state side  

Then, I sat down with my guy Bobby at the GM Goodwrench parts counter at the local chevy dealer and looked up the parts. We had to look at LSJ engine parts of course since the oil jets are not a part of the L61. The computer did list the jet assembly, but showed it as a non-available part for ordering. Couldn't even get a suggested retail price on it. The assembly is actually a rail that has all four cylinders on it and it plugs into an oil tap on one end.  

L61 is a Z22SE, in Detroit.

 

the oil jets are available seperately (I have bought some) and the block is machined to allow to to be fitted, certainly not mounted on a rail 

[speedster]

Good to know vocky . Do you have part codes for the mod?

Edited by speedster, 23 February 2015 - 05:32 PM.