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Some of you must have money trees, 36hr days, 8 day weeks, and live alone. Or just lack any experience with engineering, design, and fabrication. I have a family and a business. Both come first. It takes days weeks or months of research, hours to spec and draw a part, 26 hours of work at your day job (assuming you have no other expenses) per part to pay for one-off manufacturing costs, then assembly time.
It's time for you to stop watching car modification shows on the Discovery Channel, turn off the TV, and get your hands dirty on a project that someone hasn't built for you.
No level of your narcissistic flaming will so much as dent the pride I have in this project.
You can tell a lot about someone by how they portray themselves in public. Passive aggressive behavior is very immature. Regardless, a true car enthusiast doesn't judge someone. It's no different then a couple 16 year olds having a Camaro/Mustang pissing match. It's a sign of an uneducated mind.
lol, my friend has a rav4, i think with the same engine, and in showroom trim it runs a 14@99miles an hour in the quarter mile, which is like FD territory.
unlike the FD, there is no driver feedback in the toyota, so the black circular thing in front of the driver is terrifying to turn.
Yeah. The Tacoma is the same way. Absolutely no feedback.
Another thought. There is a TRD direct-fit supercharger kit you can buy for the Tacoma at a very reasonable price. That setup and a dead RX-8 could be a match made in heaven.
I ordered a few more parts like fuel line (black cloth), inline filter, and some more AN fittings. Trans mods were completed last year but I hadn't sealed the case yet. Should have that finished this week. I hope to have the heads cleaned and back on the shortblock this weekend. Then the valvecovers and pan get sand blasted and painted so I can get those back on. I need to examine the valve covers a bit more and decide if I'm keeping or eliminating the baffles. Either way, the engine is getting a catch can. I sent the file for the intake flanges to a shop for a quote and had the elbows in the shopping cart but couldn't check out due to the company having a $100 minimum order. I figure I have a few more months of fab before the engine goes in. Then get a custom driveshaft made, exhaust, wiring. So much to do.
Got the valvecovers stripped. Took literally hours in the sandblaster to get the old paint off of them. I started painting them with engine enamel but decided I'm going to send them out for powder coat on Monday.
Tonight I ordered the remote oil filter housing, more AN-10 fittings, the oil cooler, and a catch can.
EDIT - Monday
A second set of valve covers were sent for powdercoat this morning. They are magnesium interestingly enough. Explains why they are so light. Going with their semi-gloss finish.
I'll have to dive into the fuel pump sooner or later and started thinking about the venturi (you guys refer to it as the siphon). I wondered if I could make my own. Sure can. Works quite well.
I'll have to dive into the fuel pump sooner or later and started thinking about the venturi (you guys refer to it as the siphon). I wondered if I could make my own. Sure can. Works quite well.
nice! I have been wanting to get rid of the oem plastic venturi valve so I can fit a bigger pump in lieu of the plastic canister. how do you plan on balancing the passenger side vs. driver side tank load out with the venturi valve constantly working? I was planning on just running a line at the bottom of the tank connecting both sides, but there's always concern for catching something with the line and ripping that line out of the tank.
nice! I have been wanting to get rid of the oem plastic venturi valve so I can fit a bigger pump in lieu of the plastic canister. how do you plan on balancing the passenger side vs. driver side tank load out with the venturi valve constantly working? I was planning on just running a line at the bottom of the tank connecting both sides, but there's always concern for catching something with the line and ripping that line out of the tank.
As far as I know, the factory venturi is constantly working. It pulls the fuel from the passenger side to fill up the drivers side. Once full, it spills over back into the passenger side. Currently my DIY one is working at about 40%. For every 1 gal pumped thru the venturi, 0.4gal are drawn in the suction port. But my test methods are buckets and running water until refinement is needed.
Another thing that may be of interest to you. The Grand Prix also uses a venturi. The fuel pump has an additional outlet port with an 1/8" hose that feeds it.
Pics of the GM pump and also of a Toyota venturi (jet pump) used in some of their cars. Mitsubishi, Subaru, and many others also use jet pumps.
Since this worked so well I decided to refine the design yet keep it simple enough to use off the shelf parts. The jet I used is from a Honda lawnmower engine. Any small engine shop should have a junk carb kicking around to get the jet from. I'm not sure what size hole it is. Very small. Maybe .010".
I used an 1/8 NPT tap on the 1/8" brass T so the hose fittings would thread in deeper.
The two smaller hose fittings are 1/4" barbs to 1/8" NPT. The straight one was tapped 7mm x 0.75 for the jet. The 90 is unmodified and screwed into the side of the T and will be the suction line. The larger hose fitting is 5/16" barb to 1/8" NPT. A small section of brake line was cut and pressed into the 5/16" barb. The outside lip of the flare had to be ground slightly to fit into the T.
Sorry I don't have a more scientific method for testing this but I'm quite pleased with the results. Volumes (in the Solo cups) were after 1 minute of flow. With just the jet spraying into a cup, almost one Solo cup was filled after 1 minute of running. With the suction line connected, almost 3 cups were filled. It's drawing in more liquid then is being provided to the venturi.
Turns out that the venturi outlet is close enough to the nozzle that the brake line is not required. It had little effect on the performance and can be omitted.
The opening size of the first test jet was .026". I've drilled it to .040". I'll measure the pressure and volume tomorrow for comparison.
Anyone have a Mazda jet-pump they can send to me for measurement?
Turns out that the venturi outlet is close enough to the nozzle that the brake line is not required. It had little effect on the performance and can be omitted.
The opening size of the first test jet was .026". I've drilled it to .040". I'll measure the pressure and volume tomorrow for comparison.
Anyone have a Mazda jet-pump they can send to me for measurement?
Great info! I just drilled the opening 1/8" in my stock plastic one, through my testing it seems to work excellently, but I will be careful as I dont want to figure out it doesnt work by getting stranded lol
love it. thank you. glad you kept it up with your project. I personally really like it and appreciate your scientific methods. takes a little thick skin to ask questions and post your own work on this forum especially with a piston engine.
one thing which has been bugging me with the true fuel return conversion is that the venturi is always overworking which empties out the passenger side tank really fast. since this is where your fuel level sensor is, the fuel gauge always pegged at empty cruising around town. looking forward to your progress.
one thing which has been bugging me with the true fuel return conversion is that the venturi is always overworking which empties out the passenger side tank really fast. since this is where your fuel level sensor is, the fuel gauge always pegged at empty cruising around town.
That is interesting information. So in other words, there is a second useless gauge on the RX8's instrument cluster.
The bungs came this morning and I had them welded to the flanges today. I mentioned I'm eliminating the coolant tube that connects between the heads that normally provides a single outlet for the upper radiator hose. These adapters bolt in place of the OEM tube. The top of my radiator will also have two AN -16 ports that the lines connect to. The flanges are thick enough that I can drill ports them which will become the coolant feed lines for the turbos. The return lines tie into a tube in the valley that feeds the water pump. All the turbo cooling lines will be hard tubing that run down the valley of the engine to the rear where it'll pick up rubber hoses to the turbo.
Behold the holy oil flange of Antioch! Just sent this file to the shop. It provides the ports for my filter and cooler and also an 1/8NPT port for the turbo oil feeds, post cooler.
Valve covers came back from powdercoat. Looks good. Glad I went with a semi gloss or the casting defects would have stood out like a sore thumb. I'm getting "incorrect format" trying to upload the jpg so I can't show you. I'll try again in a bit and see if they fixed the forum.
Still waiting on the oil pump flange but I got all the AN-10 fittings for the filter and cooler except for one that got loose in the lathe. It's replacement is on the way. Still up in the air on the radiator though. May go custom.
First pic shows the water pump inlet (s). The odd looking top opening is where the thermostat goes. The round opening below it was the Isuzu heater core return. It will be ran to an expansion tank located in front of the 8's washer fluid bottle. One of the 8's heater hoses will also run to the expansion tank.
The next pic shows where the thermostat housing tube used to point. It will be routed to the radiator.
The third pic shows where it will be relocated to.
The fourth pic shows where the throttle body will now sit.
04-29-2015, 01:51 PM
