Twin Turbo LSX Datsun 280Z
04-19-2015, 04:52 PM
#722
9 Second Club
Bigger isnt always better. Longer stroke isnt always better. 408 sounds like iron, which apparently have shorter bores which on a 4" stroke again isnt always ideal
408 will push the turbos that little bit harder and away from their comfort zone.
It would be worth reviewing all datalogs, I just find it hard to believe a single incident could cause the damage, especially as oil pressure doesnt really seem to have been that low ?
Just to be sure about what the cause was
04-19-2015, 05:07 PM
#723
It's been covered in quite a few threads.
Bigger isnt always better. Longer stroke isnt always better. 408 sounds like iron, which apparently have shorter bores which on a 4" stroke again isnt always ideal
408 will push the turbos that little bit harder and away from their comfort zone.
It would be worth reviewing all datalogs, I just find it hard to believe a single incident could cause the damage, especially as oil pressure doesnt really seem to have been that low ?
Just to be sure about what the cause was
Bigger isnt always better. Longer stroke isnt always better. 408 sounds like iron, which apparently have shorter bores which on a 4" stroke again isnt always ideal
408 will push the turbos that little bit harder and away from their comfort zone.
It would be worth reviewing all datalogs, I just find it hard to believe a single incident could cause the damage, especially as oil pressure doesnt really seem to have been that low ?
Just to be sure about what the cause was
04-19-2015, 05:09 PM
#724
Oh and I know some of you may give me **** for this but I just sold my T56 super magnum and my MN12. That means I have no transmission.. I'm going auto, final decision. Well I don't know which auto but it's going to be auto for sure. I'll never get where I want to be with a 6 spd so I pulled the trigger.
04-19-2015, 05:15 PM
#725
9 Second Club
Are the auto boxes not a lot bigger physically ? How much room is there underneath ?
As said before, I've raced and driven hundreds of miles before with less than 10psi oil pressure, and all things considered bearings were good ( they were bad, but nowhere near as bad as you'd expect after cam bearings walked )
Yes I'd expect damage, but from one single incident ? You'd would need to have had no oil pressure/flow at all I'd have thought.
And if it was that bad, I'd also be concerned about the turbochargers.
Have, or can you review all datalogs ? How often was oil pressure very low ?
Right and I've read most of them. I'm aware of the benefits and drawbacks I was just making conversation. I ended up deciding on the stock stroke. I'm not sure why you think even wear across all mains and rod caps can't be caused by a single event. I think this fact is a sure fire sign of oil starvation. Regardless new bearings are in order and a new forged crank is on the way. Oil pressure safeties have been set so hopefully I don't cross this bridge again anytime soon.
Yes I'd expect damage, but from one single incident ? You'd would need to have had no oil pressure/flow at all I'd have thought.
And if it was that bad, I'd also be concerned about the turbochargers.
Have, or can you review all datalogs ? How often was oil pressure very low ?
04-19-2015, 05:47 PM
#726
It's been covered in quite a few threads.
Bigger isnt always better. Longer stroke isnt always better. 408 sounds like iron, which apparently have shorter bores which on a 4" stroke again isnt always ideal
408 will push the turbos that little bit harder and away from their comfort zone.
It would be worth reviewing all datalogs, I just find it hard to believe a single incident could cause the damage, especially as oil pressure doesnt really seem to have been that low ?
Just to be sure about what the cause was
Bigger isnt always better. Longer stroke isnt always better. 408 sounds like iron, which apparently have shorter bores which on a 4" stroke again isnt always ideal
408 will push the turbos that little bit harder and away from their comfort zone.
It would be worth reviewing all datalogs, I just find it hard to believe a single incident could cause the damage, especially as oil pressure doesnt really seem to have been that low ?
Just to be sure about what the cause was
Are the auto boxes not a lot bigger physically ? How much room is there underneath ?
As said before, I've raced and driven hundreds of miles before with less than 10psi oil pressure, and all things considered bearings were good ( they were bad, but nowhere near as bad as you'd expect after cam bearings walked )
Yes I'd expect damage, but from one single incident ? You'd would need to have had no oil pressure/flow at all I'd have thought.
And if it was that bad, I'd also be concerned about the turbochargers.
Have, or can you review all datalogs ? How often was oil pressure very low ?
As said before, I've raced and driven hundreds of miles before with less than 10psi oil pressure, and all things considered bearings were good ( they were bad, but nowhere near as bad as you'd expect after cam bearings walked )
Yes I'd expect damage, but from one single incident ? You'd would need to have had no oil pressure/flow at all I'd have thought.
And if it was that bad, I'd also be concerned about the turbochargers.
Have, or can you review all datalogs ? How often was oil pressure very low ?
Honestly these bearings are not as bad as they look. The coating is worn off which is normal and on some spots the babbit started to ball up. To be honest I could put it back together and probably be fine as it still maintains 35-40 psi hot idle. However I already have the engine out so I'm going to throw new bearings in and call it square.
04-19-2015, 06:57 PM
#729
Launching!
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Yes the 4L80E is larger but guys have made them fit. I haven't actually decided on a transmission yet as I don't know squat about autos unless it's for a diesel truck. I don't think my BTS 4R100 will fit in my Z though
Honestly these bearings are not as bad as they look. The coating is worn off which is normal and on some spots the babbit started to ball up. To be honest I could put it back together and probably be fine as it still maintains 35-40 psi hot idle. However I already have the engine out so I'm going to throw new bearings in and call it square.
Honestly these bearings are not as bad as they look. The coating is worn off which is normal and on some spots the babbit started to ball up. To be honest I could put it back together and probably be fine as it still maintains 35-40 psi hot idle. However I already have the engine out so I'm going to throw new bearings in and call it square.
04-19-2015, 09:40 PM
#734
Launching!
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Mine is different from yours, but in this picture you can see the bottom of the pan is 6"(measured) from the ground with the engine out of the car. Once bolted to the motor it will be about 1/2-3/4" higher relative to the bottom of the frame, but adding the motor will obviously drop the whole front end down.
04-19-2015, 09:43 PM
#735
If you're gonna drag race more, glide wouldn't be a bad idea since you are irs right? Would soften the launch load a lot.
04-19-2015, 09:51 PM
#736
First gear doesn't matter for top speed. It's the 1:1 without od that will cripple your top speed. Also don't forget converter slip, which means you will lose a few mph to that too. If you're going to do top speed racing still you either want to gear down quite a bit (I run a 3.25 with a 28" tire for mid 170s traps) or run something with a really strong od. The 4l80 is insanely heavy and will eat a lot of power but for an auto and your power/goals its probably your only option.
If you're gonna drag race more, glide wouldn't be a bad idea since you are irs right? Would soften the launch load a lot.
If you're gonna drag race more, glide wouldn't be a bad idea since you are irs right? Would soften the launch load a lot.
Ability to control it with the Holley but damn it's heavy. Can the glide be fit with an overdrive? Also yes I am still on the IRS and plan to keep it for awhile. Unfortunately the gear options are non existent for the R200.
Are the 4L65/70 transmissions as shitty as the 60's?
04-19-2015, 10:02 PM
#737
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Not going to lie I like the 80 for the OD/toughness and
Ability to control it with the Holley but damn it's heavy. Can the glide be fit with an overdrive? Also yes I am still on the IRS and plan to keep it for awhile. Unfortunately the gear options are non existent for the R200.
Are the 4L65/70 transmissions as shitty as the 60's?
Ability to control it with the Holley but damn it's heavy. Can the glide be fit with an overdrive? Also yes I am still on the IRS and plan to keep it for awhile. Unfortunately the gear options are non existent for the R200.
Are the 4L65/70 transmissions as shitty as the 60's?
04-19-2015, 10:06 PM
#738
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You can always run a non-OD trans & back it up w/ a GearVendors overdrive unit. Not sure what your budget is though.
Also, there are some things you can do to the oil pump to bump pressure & flow up given you're running twins now.
Also, there are some things you can do to the oil pump to bump pressure & flow up given you're running twins now.
04-19-2015, 10:10 PM
#739
Pretty sure the gear vendors is impossible to fit. Our trans tunnels are extremely small past the trans.