HowlerMonkey
-
Posts
1451 -
Joined
-
Last visited
-
Days Won
1
Content Type
Profiles
Forums
Blogs
Events
Gallery
Downloads
Store
Posts posted by HowlerMonkey
-
-
Just busy preparing the current world record standing mile holder for the texas mile.
Actually.....just seeing how far getting the last word in will continue.
-
The down side is getting stranded when it fails.
This is why toyota had a throttle cable on most of it's drive by wire engines for a few years after they were introduced.......so you could still get 20% throttle if it failed.
Straight drive by wire with no other systems affecting throttle would be ok but most every OEM version I have seen spends way too much time interpreting what it thinks you want it to do.
Manufacturers have done some strange stuff concerning the actuation as controlled by the ecu such as.......
1. opening the throttle more than the amount you are commanding to make the car feel more powerful that it really is.
2. Closing the throttle during upshifts to save a weak tranny which allows it to get through warranty period.
You should watch scope on the throttle body....it will surprise you what really is going on.
RE: the toyota thing.
There have been no cases that have even made it to court.
Toyota is around 12th on the list of "sudden acceleration" complaints based on brand with volvo being number one.
-
Hey!
Where's the 3.4L whipple?
-
Do those rods have the oil squirters that spray the bottom of the piston?
-
I was wrong and I sure don't deserve the ad hominem crap spewed in earlier posts on this thread.
I as wrong because I forgot to figure in the other "bellcranks" in the stock linkage which change the "curve" and possibly nullify the progressive nature of the geometry concerning the bellcrank at the throttle body.
Sure there is an area difference between the 60mm and 50mm throttle bodies at very small openings but the difference is just not enough to cause a huge driveability issues listed by others above since those same "surging" issues exist with the stock 50mm throttle body.
The perception of difference between the two is usually a problem since most "upgrades" that include going from 50 to 60mm usually include much more than just the throttle body alone.
Compare the difference back to back on the dyno and you find very little at same measured throttle angles.
I will get back to this at another date and prove my points with potentiometer tps data corrected to true throttle angle data with two back to back dyno runs (dyno dynamics twin retarder) on a stock L28et with both 50 and 60 but I'm very busy changing upwards of 240 valve springs per week at lexus while finishing the current official standing mile record holding car for october's texas mile competition.
Come on by and see us at the Texas Mile on october 16.
-
-
Stock linkage is not linear.
It is impossible for it to be linear through it's near 90 degrees of throttle shaft movement.
On the 280zx throttle body linkage, it starts out with the minimum authority and gains authority in relation to the throttle pedal movement the further it is opened.
-
I've replaced a VG30 with a L28et but it was in an Infiniti M30.
runs great.
-
You might be suffereing form Diabetic Nuropathy...If you can't tell the tip-in characteristics are different from a 50 and 60mm T/B using stock linkage. There is most definately a change. It's what all the butt-dyno experts attribute as 'horsepower increase' after installing the 60mm.
But this is straying from the OP's issue of on-boost modulation which is a VERY sensitive subject compared to ANY N/A car. A larger T/B will make the tip-in touchy and more power will exacerbate this. If you can feel it in a stocker with 140HP, it's worse on a turbo car with 300+!
My experience with both the 60mm and the 50mm showed me that the biggest difference in "tip in" response is the changing from the stock progressive linkage to a linear linkage......or someone modified the stock linkage to the point that the lesser authority at the beginning of the travel has been moved or negated.
-
So ColdFusion will be Cold Molding with a vacuum bag....or will you use an autoclave?
-
The stock linkage gives the pedal much less authority at the beginning of the travel and much more authority as the throttle is opened more.
I am quite fond of how it works.
When using the same articulation of the linkage, I notice no difference in response between the 50 and the 60.
Perhaps the people noting too much response at low throttle openings have swapped the stock linkage "throttle curve" with a truly linear cable....which opens the throttle "faster" than the stock linkage at the beginning of the throttle movement.
The porsche 944 has a pretty progressive throttle cam and may be a source for a more driver friendly curve.
I remembered this because I worked with Al Collins at autothority to make a linear cam for quicker throttle response on the 944 back in 1985.
-
I've seen two different crank pulley bolt lengths.
Just though I'd throw that in.
-
If I had a LD28, I would bolt up the stock 280zx turbo manifolding, swap to a 280zx turbo rear sump pan and pickup, and use the stock 5 to 6 pounds of boost to net what would be a pretty peppy yet very frugal engine in a Z car.
-
LD28 complete is worth far more than the sum of it's parts.
-
The turbo distributor could really use a counterweight on the rotor.
I use the crank trigger setup when I run a 280zx turbo ecu but now must use the distributor when using the M30 sequential ecu.
-
Just to further muddy up the topic, I had an 83 turbo and an 85 turbo, both of which had the injector cooling fan removed. I never once had a hot start issue. Both cars were daily drivers. I live in Houston, which is almost as hot as Hell in the summer
Both cars mentioned also had the hole in the hood to allow hot air to escape the engine compartment which keeps underhood temperatures drastically cooler in the case of a hot soak.....though nissan felt the need to go a step further since the repeat Z car customers have always lived with vapor lock going back to the days of asbestos covers over the fuel lines of the 260z.
Nissans reasons showed up in the new car literature at the time of manufacture both for the fans and the dual feed injectors negating the need for the fan.
I've had the ZX turbo setups (both V6 and L6) on cars that don't have a vented hood and the vapor lock issue is bad enough to prevent starting at times.
-
Carbon is building up on the valve stems which sticks them open on the -fse and -gse (direct injected) versions of these engines.
Since it happens on both of the direct injected V-6, then I assume that it's not a case an injector blowing onto the back of a hot valve since only the IS350 has both port and direct injectors....the is250 has only direct and no port injector.
My theory is that the cam timing wizardry they went through to get rid of the egr system has something to do with it since they use reversion to achieve egr.
Don't get me wrong....the IS350 screams but it's complexity tells me that it will be quite a chore to extract more hp from one.
I did dyno a IS-F that put down 500hp at performance power (owners of the 253mph ford gt) but the factory ecu did what it could to pull power above that.
It might have been trying to keep power down for the benefit of transmission longeivity, though.
I've only been back with lexus (after 5 years away) for a few months so I am still learning what issues we are having with the newer cars.
-
You might want to wait a bit on these engines and see how things go since I am replacing cam actuators, valve springs, and valves on many of them at the lexus dealership.
-
There's a reason nissan put a scoop on the turbo ZX from 1981 to 1985....and it's not there to get air in.
It's there to let air out.
The hole is there to allow convection to send hot air out the top which draws cool air in from below...the same cool air that is drawn in by the inlet of the cooling fan.
Nissan didn't need them on the 1986 and later turbos because they went to dual feed injectors that constantly returned fuel through the injector body which kept them cool.
If you have a vg30et or L28et in a car that does not feature a hole in the hood, you will experience vapor lock issues much like I experienced in my Infiniti M30 with a L28et swap.
If I went into a store for 10 minutes and came back out, the car would be unbelievably difficult to start and exhibit very rough running until I got it out into moving traffic.
After I added the cooling fan, I get no vapor lock issues after a hot soak.
-
I second the bpr7es plugs but make sure they aren't the ones with the V in the ground electrode.
My new theory is that broken piston skirts with no other damage to the pistons is from pre-ignition most likely ignited by the hot spark plug.
This pre-ignition damages very differently than detonation in these engines where you see broken ring lands or the piston top burning around toward the rings.
Every broken skirt I have seen is on the driver's side while the spark plug is on the passenger side....Hmmmm.
-
LOL....just noticed the "kaboom".
-
I've seen skirts slapped off of more than a few engines whether turbo or not.
The non-turbo car did it because some kid got the car hand me down from mom and proceeded to run to redline only seconds after starting the high mileage engine....with the engine at about 11 degrees F.
One turbo engine I had did this because the thermostat stuck open in the dead of winter while I was on the highway running hard.
I saw the temp gauge go down but that's pretty common since the temp sensors are easily stressed when pulling the connector off and will exhibit intermittence.
I figured it was the intermittence and kept at running hard and the car changed how it ran as the engine cooled rapidly.
When I pulled over on the side of the highway, the side of the block seemed to be about the same temperature as a beer out of the fridge.........guess the L28 cooling system works pretty well in 10 degree weather.
I am swapping the longblock today and may have pics of mine later on tonight.
I'll run lower boost and bring the timing back until I confirm the path from the ecu to the injectors is no longer weak causing lean condition in a cylinder or two (this is a sequential infiniti M30 ecu).
-
The inside tripod joint of the axles seems to be stock since you have to cut the metal collars to service them....and you have to change to a different style of boot retention once they are apart.
The outside could very well be non-stock and I'll bet the stub axles are improved.
-
The L24e front sump pan has the windage piece and a single strip of about 45 degrees from vertical right where the pan transitions from sump to the flat portion.
I'm swapping short blocks today and will confirm though this information probably does no good in this scenario.
removing exhaust liners?
in Nissan L6 Forum
Posted
Original poster has to ask himself why the liner got so hot that it came apart?
Does his exhaust have a restriction?
Is the timing retarded?
Time for an egt probe.
I say this because I am also running a f54 with p79 head and, even though the performance seems identical to the p90 head, I am hearing evidence of excessive heat while running low load and 4000rpms.
I'm going to swap the rods out for the ones with the oil squirters and see if this changes anything as well as hooking up egr since low load highway driving uses a bit of egr to keep combustion chamber temps down in the stock usage.