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AndrewS13
02-12-2020, 07:40 PM
I just bought a 1993 240sx with a sr20det swap. Here are the specs that I know of-

ISR 3871 turbo
Built/ported head 7500k miles
Built block -cp pistons, eagle rods, new crank, tomei procams 7500k miles
Stock ecu
Stock injectors
Stock maf

The problems I've noticed so far- rear main seal leak, running super rich, boost leaks, an exhaust leak I havent tracked down yet, antifreeze in the oil, and a bunch of oil in the inlet of the turbo and intercooler.

Since theres antifreeze in the oil, im thinking I'm going to have to redo the headgasket. And since I have to get to the rear main seal anyway, I figured I'd just pull the engine. This is only my 2nd turbo car and 1st rwd and I could use some advice as to what else I should replace while I have the engine out?

Parts I already have-
Apexi pfc with datalogit
Enjuku 750cc injectors
Z32 maf

Obviously I need a head gasket and a rear main seal, but am I best off getting an entire engine gasket rebuild kit? Or are there just a few that are important? Thanks.

S14rebuild
02-12-2020, 08:06 PM
Pull motor out, invest decent $ into proper measuring equipments and check all tolerances and spaces of the motor..
Go from there


Or find a machine shop that has years of knowledge/experience with your specific motor and have them tear down the engine and check everything and go from there...


Either way be prepaired to pay and invest $

jedi03
02-13-2020, 09:27 AM
also get the full engine gasket set...this should include the DP gasket iirc, get a seal for good (stupid thick gasket at autozone, think permex? makes it...have used them and they are great!) for the elbow to DP, measure and put some new bearings in it...but like stated above would be good to bring to machine shop that can do it and they should help do it correctly...would recommend someone who works on race engines as a lot of the others tend to mess things up...

AndrewS13
02-13-2020, 05:05 PM
also get the full engine gasket set...this should include the DP gasket iirc, get a seal for good (stupid thick gasket at autozone, think permex? makes it...have used them and they are great!) for the elbow to DP, measure and put some new bearings in it...but like stated above would be good to bring to machine shop that can do it and they should help do it correctly...would recommend someone who works on race engines as a lot of the others tend to mess things up...

When you say DP gasket, are you talking about the downpipe? And put new bearings in what?

So far my plan is to pull engine, inspect, and rebuild with a gasket kit. Thoughts on this one?
https://www.enjukuracing.com/products/isr-performance-oe-replacement-engine-gasket-kit-nissan-sr20det-s13.html

I'm also going to rebuild the turbo as there is a decent amount of shaft play. I can just use a rebuild kit for a gt2871r right? Im pretty sure they're essentially the same turbo just ball bearing vs journey bearing.

This isn't my first turbo engine rebuild and I'll have help. Its just my first sr20 and s chassis

TheRealSy90
02-13-2020, 05:47 PM
I'm also going to rebuild the turbo as there is a decent amount of shaft play. I can just use a rebuild kit for a gt2871r right? Im pretty sure they're essentially the same turbo just ball bearing vs journey bearing.

Ball bearing CHRA's aren't really rebuildable.

AndrewS13
02-13-2020, 06:00 PM
Ball bearing CHRA's aren't really rebuildable.

So do I have any options here other than getting a new turbo? If I need to get a new turbo am I best going back to stock turbo and keeping stock ecu set up? Im only looking for 300-350hp

mechanicalmoron
02-13-2020, 06:23 PM
Does the turbo made bad noises, or turn hard, or have any scoring or fin damage?

Not saying cheap out on a turbo and risk your motor eating it, but oil in the intake and being able to wiggle the (smooth and nice feeling, unchipped) compressor wheel a bit is par for the course with any vehicle with a turbo.

If you need a head gasket you need a gasket kit or the balls and experience and materials to make and fake the gaskets you need. If you've rebuilt motors you should have some sort of feeling about all these questions you're asking...

S14rebuild
02-13-2020, 07:25 PM
Worryn bout a turbo when the motor has issues.....

AndrewS13
02-13-2020, 08:41 PM
Does the turbo made bad noises, or turn hard, or have any scoring or fin damage?

Not saying cheap out on a turbo and risk your motor eating it, but oil in the intake and being able to wiggle the (smooth and nice feeling, unchipped) compressor wheel a bit is par for the course with any vehicle with a turbo.

If you need a head gasket you need a gasket kit or the balls and experience and materials to make and fake the gaskets you need. If you've rebuilt motors you should have some sort of feeling about all these questions you're asking...

Thanks. Definitely more play than the t25, 14b, and 20g turbos i've had. And wayyyyyyyyyy more oil EVERYWHERE. I have a feeling there's a bunch of engine blow by, going to do a compression test to confirm. I just don't trust this turbo so i was asking if they were able to be rebuilt like my td05... I think the turbos still good but I don't trust it long term especially on a freshly rebuilt motor.

AndrewS13
02-13-2020, 08:42 PM
Worryn bout a turbo when the motor has issues.....

Just trying to plan my rebuild. Thanks for the input.

jedi03
02-18-2020, 03:18 PM
look at twisted motion for help on lower cost for turbo...tear it down, measure it correctly and put it back together!

AndrewS13
02-18-2020, 04:31 PM
look at twisted motion for help on lower cost for turbo...tear it down, measure it correctly and put it back together!

Thanks. Engines ready to be pulled and should be on a stand this weekend. I have the s14 sr20det FSM downloaded so i'll most likely just do the measurements myself. If anything looks odd I'll be taking it to a local machine shop that did work on my 4g63 to check it out. Couldn't find anyone that has a lot of experience with sr20s.

I definitely think the turbo can be salvaged at least temporarily until im ready to upgrade to a bigger turbo. Thank you for the twisted motion tip. I'll look into them.

jedi03
02-19-2020, 10:43 AM
if you have a good micrometer like https://www.grainger.com/product/2ZTX8?cm_mmc=PPC:+MSN+PLA&s_kwcid=AL!2966!10!8973609251!1102900009041&ef_id=Xk1h6gAAAcT0vGcR:20200219162722:s and know how to use it definitely! I would also suggest a bore guage (think that should be able to measure the crank journals too) so that you can tell if the block has had the bottom end machined as well...if it didn't spin a bearing or the bearings don't look to worn sometimes you can get away with just measuring the bearing and get a same size set...also don't skimp on the replacement of wear parts...they aren't that expensive, also would suggest re-do freeze plugs, and actually remove them, not just push them in...its been recommended to me to use bronze as they don't weld themselves in like the steel ones do