First time at the drag strip...had some problems.

[compactfean]

First off, car ran great but I couldnt even setup my boost controller or tune my ecu because I just barely got it up and running and ran out if time. ...next time. I had three main issues.
1_ wheel hop. I have all poly bushings in the back and those subframe insert things that came in the 240sx master kit...any good? Stock sway bars which I plan on upgrading (yes I will remove the front before hand) lowering springs with stock struts, any suggestions? (and please not "get drag struts") z32 tt bfg street tires and shimmed j30 diff.
2 trans- first gear kept popping out, clutch is brand new act which makes me think trans. Any good how to's on rebuilds or syncro replacement? If that's even the problem.
3 blow by- I've got a tiny catch can and I left the outlet open to see how much I was loosing...needless to say because of my vented hood I had to clean my windshield. I'm running open bov and someone said that that will cause cylinders to wash down. Is this true? If so that might help im sure on the blow by pressure because it only seamed to do that by like third gear. Also the blow by air id like to run it to the intake so it can be metered but dont want oil in my intake so any catch can setups that work really well? Btw engine compression tests fine and doesnt smoke or anything.

Thanks for any input and help guys.

[kingtal0n]

First off, car ran great but I couldnt even setup my boost controller or tune my ecu because I just barely got it up and running and ran out if time. ...next time. I had three main issues.
1_ wheel hop. I have all poly bushings in the back and those subframe insert things that came in the 240sx master kit...any good? Stock sway bars which I plan on upgrading (yes I will remove the front before hand) lowering springs with stock struts, any suggestions? (and please not "get drag struts") z32 tt bfg street tires and shimmed j30 diff.
2 trans- first gear kept popping out, clutch is brand new act which makes me think trans. Any good how to's on rebuilds or syncro replacement? If that's even the problem.
3 blow by- I've got a tiny catch can and I left the outlet open to see how much I was loosing...needless to say because of my vented hood I had to clean my windshield. I'm running open bov and someone said that that will cause cylinders to wash down. Is this true? If so that might help im sure on the blow by pressure because it only seamed to do that by like third gear. Also the blow by air id like to run it to the intake so it can be metered but dont want oil in my intake so any catch can setups that work really well? Btw engine compression tests fine and doesnt smoke or anything.

Thanks for any input and help guys.

I dont see what engine but I assume SR20det? Stock turbocharger?

The proper way is the valvecover -> catch can -> turbo inlet (as you mentioned) as long as the line is free-flowing (no restriction) this will work fine.
But you should not be having massive amounts of oil running out of the valve cover. that is an indication of bad piston rings or bad oil control.

What weight oil are you using?
Is the engine OEM internals? OEM oil pump? anything modified in the oil line for the turbocharger?
if you are using OEM internals and anything thicker than 10W-30 you need to switch to 10W-30 right away.

Open blow-off valves will reduce piston ring life by washing the cylinder walls with fuel, its true. By how much? No one can say... but recirculating the blow-off valve will improve engine life and fuel economy for sure, and especially oil life. Your problem with blow-by can be related to thin oil from fuel contamination due to the atmospheric blow-off valve... which is why I keep mentioning viscosity.

reply with more details about the engine and I will try to reply with more helpful information

EDIT: I just read about the 3071 and "full built" so now I have more direct questions:
What oil line are you using for the turbocharger feed? did you change or mess with restrictors?
What oil pump is in the engine? What weight oil using? what are the bearing clearances? What pistons/rods are you using? was anything done to lighten the crankshaft? What valvesprings/cams are you using? What boost settings and what brand intercooler? MAF or MAP sensor? OEM ecu or stand alone? who tuned it and how does it run? Does the engine ever smoke? Do you have a wideband gauge? what is the air fuel ratio during WOT/Cruise etc.... Does it run closed loop (narrowband sensor installed? maintains 14.7:1?)

Start with that lol

[compactfean]

Yes its an sr20det, gt3071r turbo. I have my catch can setup excactly like that but the stock one i removed....maybe putting that one back might help?, but I dont have it ran to the intake yet until I solve the oil issue.
The internals, cp pistons, hks sleeves, eagle rods, oem oil pump. Braided turbo lines with a gt dual ball bearing oil restrictor. Running 15/50 mobile which is what me and all my drift buddies run. Bearings where all stock spec acl and crank was micropolished and balanced with the rest.
Cams are tomei 260 with tomei red valve springs, bc retainers, tomei solid lifters.
Greddy intercooler, z32 maf. Boost was 14 -17 psi as far as afr, cruising is between 14-15, wot 10.5-11.3 and idle is 12-13. Ecu is an e-prom tune from e-mance and I have my emu for fine tuning. (which wouldn't communicate on race night) car only smokes on wot if afr is in the 10s. Car runs great otherwise. I ran a 13.3 and a 2.2 60 ft from the trans pooping out of first. Stock o2 is there to keap the stock ecu happy....can't think of anything else. Lol

[kingtal0n]

Youve got to figure out if you are having a blow-by issue or an oil control issue.

Inspect the underside of the valve cover. There is normally an oil control "baffle" section that allows oil to splash all over the place without getting into the breather.

IF oil is getting up into the breather then:
A: The baffle is malfunctioning / missing
B: The baffle is insufficient for the oil splash/pressure/viscosity/conditions etc...
C: The baffle is working fine and the engine is just blowing by compression into the valve cover

So I would suggest a leakdown test for all 4 cylinders while cold, then while hot. If its fairly high when cold but it drops low while hot (11% -> 4%) then its probably fine (it should do this I think those pistons are low silicone alloy).
If its fairly high all the time (COLD AND HOT) Then you may simply have wildly large clearance (such as piston/wall) or you have an actual compression leak somewhere (such as valve seal/spark plug/head gasket/stuck valve/etc...)
The leakdown will help but it still will not tell all. you can have a wide piston/wall and still get good leakdown #'s, but its a start at least.
Does the oil seem to blacken up soon after it is added to the engine? A freshly rebuilt engine should maintain new looking oil, when you pull the dipstick after 1000 miles it should look like you just changed it. If the oil is blackening up quickly, it could be another indicator that the compression is leaking past the rings. that hot combustion is burning the oil, blackening it, like charcoal. exactly like charcoal, as oil is just chains of carbon, you add some heat in the presence of oxygen and the chains break apart to bind oxygen. If it gets INTO the cylinder it can cause detonation and raise the compression ratio. if it gets into the oil you get black dirty oil.
Other conditions such as extremely rich conditions can also blacken oil quickly, so do not take this as a sole indicator of piston ring problems. We are just trying to tie the pieces together.
Since you cannot easily change rings the best idea at this point is to:
A: do a leakdown and write down the numbers and factor this to the equation
B: recirculate the blow-off valve to the intake before the turbocharger
C: utilize a catch can that is easy to see the oil level and take an accurate estimation of how much oil you are losing and under what conditions.
make sure the plumbing is [valve cover->catch can ->turbocharger inlet](just like factory) verify that the inlet is not getting oil inside it by inspecting it and the catch can often. this is a diagnostic tool not so much a permanent installation, we are trying to diagnose the actual problem.


When an engine is built with "OEM SPEC" ACL bearing basically you are adding clearance everywhere (oem is about .0008-.0012 or something like that, with ACL you probably wind up around .0022~) SO using thicker oil is fine (necessary even perhaps) but the oil pressure will help decide, and just for the sake of comparison I would try a 40W and 30W oil also to see if it makes any notable difference in anything. You should have an oil pressure gauge regardless in an engine witha built bottom end.
and THICKER OIL is not BETTER. I have seen the OEM oil pump in several engines fail (RB25, SR20) possibly due to utilizing too thick of an oil! People that try 50W racing oil with OEM bearing clearances... yikes that scares me a little.

[compactfean]

well you have brought up some great points! Some that I'm sure no one else would have brought up. There is an oil baffle type plate that I removed because of the rocker arm stoppers that were installed. Maybe I'll try making a bigger custom baffle where the stock one was...(stock one didn't fit) also the oil pan I'm running didn't allow for the lowest baffle to fit...does that one make much of difference since its all the way down at the bottom?
Also as far as the catch can, I've been trying to find a decently priced catch can that actually has screens or a filter element. The one I have now has very small inlet and outlet and spits out raw oil so its not very efficient. I got it from a friend and I think its just a cheap ebay. Any suvgestions?
As far as the bearings, they were still within spec but yes, all were .00017 to .00018. A little on the loose side.
So,
1, ill recurc the bov
2 put the stock crankcase breather/catch can back on
3 do a custom oil baffle
4 not sure what after market catch can to run from valve cover to intake
5 leak down once I have a chance to barrow my buddies gauge setup.
6 bottom baffle?
7 wheel hop?
8 trans?

[compactfean]

So I found out what was going on with the oil issue. The catch can that I was using, the inlet and outlet were too small and causing pressure in the crankcase to build up. When the pressure built up it would force oil up the dipstick tube and spray out until the pressure leveled. Lesson here, dont use catch cans with a smaller diameter than the stock setup had. And actually, there wasn't even any oil I'm the lines or anything to the catch can or in it....but it looked like from where it was spraying from, that it was oil coming out of the catch can.

This makes me much more happy, because I just built this motor only a couple years ago. What I did is used my stock catch can and rerouted and mounted it so that the valve cover has only one exit, which goes to a T in between the crankcase outlet and stock catch can. Then the outlet goes to the intake. It hasn't been very long but I haven't had an oily windshield yet! Lol
Ill eventually get a larger catch can that goes to the stock catch can and the intake so I can measure how much I'm loosing. But so far 1000 times better.
I'll let you guys know.
The other things though is the 1st geat popping, what even causes that? If I tone down the launch control will that help?
And wheel hop?

[blkvrtswp]

1st gear popping out - make sure you did not install the trans boot seal BACKWARDS. The largest one that seals the outside from the car interior and has a metal hold-down ring with 4 bolts.

It has a subtle tilt to it and if backwards the rubber actively pushes against the shift lever sometimes causing it to pop out of 1st, 3rd and 5th.

[moso]

the stock shocks are definitely the cause of your wheel hop, get stiffer dampeners, you should be able to spin your tires with no wheel hop. i run agx2 with tien s-tec lowering springs and i can free spin both tires on dry pavement (shimmed vlsd, n/a ka, es bushing kit, 350z rims w/ khumo ecsta ast ).

[compactfean]

Damn we have almost the same setup, lol. I was looking at the agx or the adjustable tanabe struts. Thanks guys, if new struts solves my wheel hop issue than all I got left to figure out is my trani. Rebuild or upgrade .