If you are rebuilding;
Have forged expensive pistons at 86 or 86.5mm, then rebuild the 3sgte,
Otherwise don’t bother with a 3sgte block, get a cheap 5sfe block (around $100) and get pistons to suit (either 3sgte at 87 or better 87.5, or better again however more machining costs (small in comparison to total costs) + stroker forged pistons though are similar cost to 3sgte forged pistons). Both 5s builds will need this head gasket
http://www.atsracing.com/...etails/E-5S-HEADGASKET . No power gain 5sgte but more power at lower rpm, more torque, stronger block to tolerate track abuse.
Second, sump. Gen 3 sumps are hard to get, oil pumps etc can be hard to get as they are only for that gen. Gen 3 Oil pump runs a smaller cog (you need to buy separate generally) and will need a Gen3/4/5 timing belt. That leaves you with a slightly higher running pump than the gen2 due to the cog not the pump.
Gen2 you can buy a 5sfe (currently $150 delivered)/highflow/ats racing oil pump (15.x gator)
http://www.atsracing.com/Parts/Details/E-OILPUMP that will outflow the Gen3 pump (13.x gator). Must read
https://mr2.org.nz/forum/viewtopic.php?t=8741 to understand the pumps.
However gen4/5 sump has a larger gator/pump at 15.x the same as the highflow, running the smaller cog and outflows the others, has a camshaft sensor (need to buy camshaft pulley, sensor and ecu to accept crankshaft signal). This ends up being the same as the highflow pump with smaller cog so 26% greater flow than Gen2.
All oil pumps have a relief valve, depending on factors, the oil pressure at mid-high rpm is bled off from increasing.
ACL high volume pump - what’s the cost listed by the mechanic / more than $150. The shop has great reviews and look after mr2 however the supplier list passenger vehicle pump for 3sgte
http://www.raceseriesoilpumps.com/oil-pump-applications.html Unless they have a listing on how they engineered it to be better than toyota solutions available and specify their race series specs for 3sgte.
None of the above sumps will help with g-forces of serious track work. Other solutions from supply canister (pressure valve) through to dry sumps however more expensive.
There is also the moroso sump that is very popular with the gen2 highflow (ats Racing/5sfe) pump used on mr2 that track. The moroso sump offers a higher capacity of oil and baffling.
https://twosrus.com/catalog/product_info.php?products_id=807 lots of suppliers out there just a quick google grab. Again not saying a toyota or moroso sump is the be all and end all to solve oil track issues - but it’s improvements.
Lastly what camshafts are you running. Camshafts, turbo, boost pressure, various factors that create an unbalanced engine lead to quicker death.
Blocks; 3sgte Gen 2 is delicate, 3sgte Gen 3 is stronger, Gen 4/5 (caldina) is the later design, 5sgte (aka 98+ block
https://www.mr2oc.com/61-3sgte-turbo/395274-how-build-5sgte.html ) is the strongest of the series for race/pushing.
post edited by TonyMR2 - Monday, July 01, 2019 7:59 PM