Tony D
-
Posts
9963 -
Joined
-
Last visited
-
Days Won
74
Content Type
Profiles
Forums
Blogs
Events
Gallery
Downloads
Store
Posts posted by Tony D
-
-
It all depends on what speed and load they are generating.
Do a dyno pull from 1000 rpms in 4th gear and look at the power generation of that engine. Plot 25HP.
Then extrapolate 5th gear and 25hp. That's as low as you can go and likely keep forward momentum on a level highway at 65-70mph.
Now, put a load like a 5% grade. Just add boost. Right?
It's an extreme, but demonstrates that while you might be able to do some things, it may not be best advisable.
Shifting to 5th gear at below 45mph is lugging the engine. But you can do it. Now climb a hill with it. Just add boost, right?
-
You going to try and take away a bat from an unstable teen...
WATCH ME!
I've taken bats away from a lot bigger people than some spoiled brat on a rampage...
-
I've never seen a better commercial for spanking your kids than some of these videos...
Actually, I was thinking more on the lines of condom commercials than spanking...
-
Good point on the distributor. I cut my plate to allow reverse rotation so underboost the breaker plate moved backwards and retarded timing. I think I was set at 24 total under 10psi of boost. That was pretty agressive, I ended up dialing it back to 18 and could run on normal gas then.
I got 5mpg on boost as well...17 in daily commuter duty though. Not bad for as heavy a foot as I have.
-
"Shifted to second gear at 7000 rpm and then the engine surged, suspected vapor lock. Stopped car, looked at the float windows and as I suspected from the engine reaction they were empty, no fuel. Back to the garage again adjusted the fuel pressure regulator to the maximum pressure setting, tried the same drive again and vapor lock a second after shifting to second gear at W.O.T."
I agree with yerbetten! You need something that will produce at least 3.5 psi more than the boost level you intend to run. I know a kid in AZ that was going through L28ET's like there was no tomorrow runing a Holley Red...everytime he got to 12psi of boost, BOOM the thing ran lean and detonated to death!
Holly only produces 15psi at best conditions! HE was overpowering the fuel pump with boost and the air was going backwards down the fuel line!
This is the same scenario with yours. If you look at the Lotus Esprit Photo I posted, you will see in the lower right hand corner a small pressure regulator, that is what you need. It will reference boost pressure and keep fuel pressure a set delta-p above it to prevent gradual running lean as boost comes on...
This was a very common occurance in the VW world decades ago---there was a misconception that you couldn't run boost more than 2-3 psi because 'the fuel pump won't keep up'---wrong. They are sealed on the VW, and you can vent boost to the lower chamber of the fuel pump to make the mechanical unit boost regulated to 3.5 psi over boost pressure on them, no problem! But if you don't they only make aroudn 5psi terminally and once you hit 2-3 psi you start running lean. Do it hard run style and you blow air into the tank! (Or at least stop it from entering the carb at all as the pump can't overcome the air pressure!)
YOU GOT LUCKY THIS FAR! IMO you're running on borrowed time, runing dry on a turbo causes exactly what yerbetten stated: "ping bang boom!"
That's just about all the warning you will get one of these times. Could be the next time, the time after, but eventually it WILL happen if you don't get a pressure and flow capable pump. Most carb rated pumps are only good to 9-12 psi because they are terminally rated to produce 12-15psi. EFI pumps are great because they're everywhere flow like crazy at 20 psi, and are quieter than most carb pumps. Hell, a stock N/A pump works GREAT! (Cheap, and readily available, too!)
-
I learned years ago to carry an extra pair of socks in the car...
Sometimes you get this feeling at a remote desert filling station about how often their premium tank is actually turned over...
So you whip out the old nozzle, slip a double sock on it, and GO FOR IT! Live life on the edge...
Later, as you realize the red stains on the socks were not from the last time you walked barefoot from the tent to the Z in a stupor...as the car vapor locks and comes to a stop on the hills outside ABQ NM... That maybe, just maybe you got a bad tank of gas. And even going in with protection didn't stop the gas crabs from making your day terrible.
Then you get to lie on your back changing the large filter you just installed before the trip, thinking it was big enough to 'last a lifetime' but in reality it only took one dirty deed in the remote desert wilds of Arizona to make your nozzles do nothing but drip drip drip with a reddish tinge and a full heart of regret for what you did the night before...
-
1
-
-
Mr. Bell and I have some disagreements on other aspects of his published works...
-
I've run N42 stock Nissan Pistons in my turbo car for over 40K miles...
If you are sinking rings and lands, it's NOT the pistons' fault!
I've run 21psi on the stock N42 pistons, though most of the time I'm running in anywhere from the 12 to 17psi range. The engine started at 12psi, and it's the lowest boost it's seen since startup. This is a JDM engine, that came out of a car, so it's not like these were new parts I was starting with, either.
I think the point XNKE makes is valid. Sometimes people get blinders on to the forest, and then can't see it because of all the trees in the way!
-
Do you have the steel pan reinforcements in place?
Critical for a proper compression of the gasket. The MSA super duper gasket is more designed for rigid cast pans than sheetmetal ones. If you insist on using it, you need the rail reinforcements.
Frankly, I cut and made my own out of strap steel, from Lowes (Or Home Depot, I forget now) Combined with the stock L28ET reinforcements the entire pan is girded with a nice thick support. It sandwiched the pan and gasket against the block.
I also made my own stud kit, and use flanged-headed nuts with serrated anti-loosening feature so once they were tight, they didnt' slacken off.
Worked well to this point.
Then again, I believe I used a cheap cork gasket like originally in place and that worked for 100K plus miles before I opened it up!
I got a super dooper MSA gasket hanging on the wall---they make a GREAT pattern for transferring bolt patterns when you make your own pan stiffener rails!
-
Lotus did it better, though, and more completley dominating! Everything you want to know about blowthrough applications can be learned from closely studying the BiTurbo and especially the Turbo Lotus Esprit!
-
"This posting has been deleted by its author."
Too late for me, I guess!
-
We had a 240Z that was vapor locking in daily driving only after highway runs. We put a makeshift fuel cooler into the car that was constructed out of a one-gallon igloo cooler and copper coils, we could put a whole 7# bag of ice in there, and it would prevent (ABSOLUTELY) any vapor locking of the vechile under any conditions. One thing we noticed was that after 2 hours of highway driving the ice was totally gone and the water was up to near ambient temperature in the engine bay (around 140 on a 90-100 degree day). We realized that as the tank got lower, the ability of the fuel in the tank to act as a heat sink and dissipate absorbed heat picked up from the engine bay was less and less.
People with EFI cars have noticed their AFR's go crazy sometimes when they operate high specific output cars with less than 1/2 or 1/4 of a tank. The fuel heating affects the heat content of the fuel (BTU's)---this is the impetus for requiring fuel dispensers to be temperature compensated. Fueling stations make money selling 'hot fuel' later in the day than they do in the morning and overnight when the fuel can be as cool as 58F. Even small changes in gasoline can make for a large (up to 10+%) difference in volume. When everyone says their injectors are 550cc, do they mean at 60F, or a 160F. The heating value of the 550ccs delivered at 60F will be far different than 550CC's at 160F. We generally use volume delivery systems, which are uncompensated for temperature (air temp on EFI helps). When you do that, your power levels are inconsistent. Drag racers chill the fuel not only for maximum density, but for maximum consistency---taking fuel temperature out of the equation leaves only air density, and they measure that and jet accordingly. No cool can and your air density measurement is a guess in the dark!
Depending on the temperature of the fuel delivered, it's heating content can vary GREATLY! Combined with air density that will not be changing at the same relative rate... and you have an issue.
Small power steering coolers were always on my mind as fuel coolers. The factory rally cars in European Winter Campaigns had differential coolers in the fuel tanks! Helped keep the fuel warmer to prevent icing of the tripple carbs in winter rallys.
In short, if the cooler is on the return, the goal is to lower the temperature on the return and keep it from rising above ambient (the assumption that fuel in the tank is at ambient temperature is seriously flawed, get a temp gun and take a reading sometime, the only time It's at ambient is before you start the car in the AM. After that, it is consistently, and in some cases considerably above ambient temperature!)
If the cooler is on the fuel feed side, it has to incorporate some sort of artifical cooling (running the line along the A/C Cold Line, inside the insulation for instance, or ice bath coolers) to lower fuel temperatures for highest density and consistent fuel delivery temperatures.
Note the Z31 computer uses a fuel temperature sensor, and has a compensation table to go with it... Even Nissan acknowledge there was an effect on emissions and power that is related to the temperature of the fuel.
-
That's a generous and flawed assumption to make based on an engine output plaque.
Manufacturing difference can mean as much horsepower is lost in transmission as from production tolerances.
Taking a factory HP rating from an era when there were no standards for measuring it, and then comparing the results to current dyno comparisons is foolish.
What if the rear wheel said 127HP, then this car only lost 23HP---then how do you account for a 45 HP loss on one vehicle, and another identical vehicle in similar trim makes 127 on the same dyno, or on a different dyno for that matter? What of a power peak different than claimed on the factory documentation, frictional losses building as speeds climb skewing it downward (if I'm reading your post correctly)?
The rating on the plate is useless. And certianly is not a basis for making a claim of 45 HP lost through the driveline. That is just foolishness.
Good to see the OP got the thing dialed in, looks like it was a Tachometer Error.
As for loafing along at 2800 in a turbocharged car, hope your oil pump is up to the challenge. Most people are looking for a 2000 rpms cruise speed, and that just doesnt' supply required oil flows for longevity IMO. You can do what you want, but oil pump performance curves and bearing loads are very definite science. And lugging an engine is lugging an engine.
-
... Including donating their penile skin as seat coverings!? Whiskey Tango Foxtrot! In all my reading of nature books in and out of school, I never saw anything about whales giving up the skin from their weiner to be used as leather.
Jobs nobody talks about but someone has to do: Wale Moyle.
Pay isn't great...
BUT THE TIPS ARE BIG!
Yadayadayada, I'll be here all week, you've been a great audience, don't forget to remember your table attendants, I get a cut!
-
Computer Lab...LOL
As someone who watched that at a Chrysler Training Seminar (and it was old then!) finding new life makes the thing a living entity amongst people doing mechanical work.
This made the rounds at Honeywell Engine Boosting Systems about 10 years ago as well (then Allied Signal / Garrett).
Anybody remember the 16mm Training Movies with "Primitive Pete" in them, the guy who could fix anything with his big, rock hammer? Apparently that was not just a military thing as well---Ford used that training film in corporate training to great effect on RCSM's.
-
I must put Y0RGO onto this thread, just so he can use that photo later elsewhere.
It is truly worthy of repititous posting...
-
Yeah real gangsters shoot semi-automatic SKSs...
Yeah, I don't see the 'keyhole' in front of the trigger guard.
Not that I have any knowledge other than entertainment indulgence in such a modification for an SKS...
-
I'm in line with Braap's comentary. My only caveat would be idle vacuum. With the MAP based system you have now, you will need some idle vacuum to get the requsite resolution to have an engine that will idle well while on computer control. If you go too radical, the vacuum won't be there, and idle quality will suffer.
As you suggest, Megasquirt would be the next step, and it would suffer the same from lack of idle vacuum (there is a big resolution difference from 35-105kpa, as opposed to 60-105kpa, as a 'big lopey overlapped cam' might give you)
But luckily, the MS comes with an Alpha-N mode, so you can tune based on throttle position and rpm...works fine on the track and with the expanded maps you have plenty of resolution for tuning drivability to and from the track.
Now that you have mentioned this, I need to drop Rick Patton an e-mail. He's got 50# of my SU Carbs for about a year now (all the Datsun SU's, 65-78) so he could make up appropriate drop-in Injection Kits for all of them. I need to see where he's at on that, and see when my stuff is headed back my way. I need to put some of that stuff back onto cars!
Good to see your car is working out well after the conversion Caen! Sorry I didn't drop you a line, I was at Spa again last month for the 6 Hour Oldtimer event. Maybe next year!
-
BOLLOCKS! (like the local lingo attempt?) There were at least a Dozen of them in use at the muscle car weekend at Eastern Creek last month. They have to be getting them from somewhere. If all else fails Demon Tweeks out of the UK sells them.
Also JC Whitney sells one, not the Weber/SK unit, but very similar (gauge and needle design) --- JC Whitney will ship as well, and the one they sell is probably about half the price that Demon Tweeks wants for the Weber one.
I have had the JC Whitney one since 1986, and it hasn't failed me yet.
Matter of fact, I stand corrected, I just googled "jc whitney synchrometer" and it pops up with the SK/Weber one for $88 US, and the other one for $55 is the crappy uni-synch. I searched one back from the page with the Weber Synchrometer on it, and up pops my old favorite the Schleyer one that I bought from JCW while I was stationed in Japan in 86---it's a whole $40 US, and I can attest it works just as good as the one costing twice as much, and 1000X better than that overpriced piece of die-cast sh*t sold by Uni-Synch!
Weber One:
JC Whitney P/N 14219G
Schleyer One:
JC Whitney P/N 1JA882792 Schleyer P/N 200+H10+18
Not all the Webers will have the air bypass equalizing screw. That is a later model response to Dellorto which had them, and allows for compensation of a twisted throttle shaft and butterflies that aren't quite in line after sticking and throttle stomping too much...
-
Either I missed the earlier post showing the 50mm Stocker Cross section...or someone edited it to include it afterwards...
That shows the 50mm unit is considerably larger cross-sectionally than the smaller pairs. This tends towards the 'sport feel' of the Earlier Cars versus the JDM later version ZX's with more of a GT Tuned Feel (or a Cedric/Gloria for that matter.)
Strong tip-in response makes for a more sporty feel and the perception that there is more power there than there really is!
-
"Engine speed is over 9,000 Revolutions per Minute (RPM)."
So much for that crank harmonic, huh?
I have one of the old heads off that boat. No, you may not have it.
LOL
-
Man, leave for a little while and this pops up?
But a nice spunky conversation going on...
Soon all the excitement will cease, and it will shrink back into the shadows...
-
A Datsun in a Motorboat? Say it ain't so!
Check out a search for a small Hydro that ran in the UNlimited 2.5L Class called the 'Sho Nuff'...especially if you can get video clips. I can't link any now due to sucky internet. You should pull a ski fine!
-
At the Dennys once a month. San Diego Z Car Club, they're online.
Whiskey Tango Foxtrot! In all my reading of nature books in and out of school, I never saw anything about whales giving up the skin from their weiner to be used as leather.
Found Something to Replace the Mini Bike of Death
in Non Tech Board
Posted
This link, of course, has been forwarded to The Boy under the subject heading "Why aren't you doing something constructive like this?"