In the mean time, I've had a couple of email chats with Mark Eberhardt, and one of his suggestions tickles the mind: Why not gut the webers and use them as TBs? Thinking this further, the Webers don't even need gutting (although it might improve airflow a bit when the venturi for the main jets is pulled out of the inlet area, and the main venturi is removed. The first is certainly possible. I'll check for the latter.) Then the injectors can be placed either as shower injectors inside the air filter house, over the trumpets, or could be machined into the 45 degree intake manifolds between the Webers and the engine. The shower thing is intriguing. That would make the mod 100% reversible. In fact, it would also make it 98% stealth. Just two fuel lines and a bundle of wires coming from the air filter housing would be the tell-tales. And these could be placed out of sight, in the bottom of the housing. Question is if there will be enough room over the trumpets for the injectors (when using the low-profile piëzo injectors that the Hayabusa also uses). I am definitely going to look into this option! Sean, I understood from Mark that you are going to give his multi-MAP setup a go? I want to use that one too, but will wait for you to iron out all the built-in frustrations This is fun!!!!
some info for the guys doing the multi-MAP sensors, if you run some calcs on the intake cam profiles for all the cylinders and note the lobe separation not between A-E but A-A you'll find the overlap of intake pulses. all 8 cycles occur within 360* which invariably will leave you with a fair amount of overlap depending upon profile. this overlap is where the pulses occur and with short runners on the carb setup they will be fairly noticeable at low velocity. this will also increase the scavaging of the previous cyl, for ex. cyl 1 is not complete in cylce when cyl 5 starts, if the runner is to short the lower pressure port at cyl 5 will draw flow from cyl 1, if it's longer then cyl will only see a static pressure volume. at increased rpms this dynamic changes further. also the A-E overlap plays into this as well. I'm wondering if the CPU can process the info fast enough on a mutli-map setup as these events happen in .00n seconds. this is the biggest issue to deal with on ITB's at low velocity.
Yeah that is a neat idea Mke mentioned with he shower injectors and gutted Webers. I would do that if I had Webers ... keep us posted! Ferraripilot ... you listening ? Yes I'm going to play with the multi map board. It'll be interesting to look at with a scope. I'm really curious how clean and repeatable the signal will be. It should look like some of the intake pulses guys see on their engine simulations. cheers
Once you see shower injectors in action you'll see how they got their name. BTW, isn't this usually called 'throttle body' injection? I was chasing a problem with my '91 olds wagon & was idling the engine with the cover off of the throttle body. Gas was coming out of the injectors in a smooth shower. Couldn't have been a lot of pressure behind it as it wasn't a spray, just a smooth flowing shower! Throttle body injection was short lived before it was superced by port injection. What was the big advantage of port injection had over throttle body injection?
Primary advantage->Better fuel atomization, then semi-sequential, then later sequential which all translates into more power, better fuel consumption and less emissions.
Yes Sean, I am heavily involved in the whole shower injector thing as well. I am essentially looking into mounting the shower injectors directly to the carb horns similar to how Ducati mounted theirs to the 996. We are working out height issues and fuel rail issues at the moment. Everything is on paper so far but we will post pics once something is actually done, if I do it. Still pondering. Furthermore, I did some digging on shower injectors and found a good number of Honda and BMW tuners who picked up 10-15bhp at the wheels swapping from regular ITB injection to shower injection. The fuel atomization really is that much better.
no... port injection doesnt always translate to more power compared to over throttle body injectors. at least not in purposed built race car motors and motorcycles
Which is why we see many setups with half and half. Port injecter and shower injector. The big issue with shower injection only was off idle performance until some newer gen shower injectors came out which are supposedly much better.
Hey, we're talking about replacing Webers here. It's not like these are silky smooth coming off the idle... I really like the stealth and the reversibility aspects of this idea. The only thing one can see from the outside is a bunch of webers, two fuel lines coming from underneath the air box (so invisible) and a bunch of small air tubes running to the MAP sensors. THAT would be the only thing having any impact: drilling and tapping the intake manifolds for 8 hose fittings and some air hoses. Not really a big deal, and easy to close off if for some reason one would want to step back to Webers.... Even all Weber fuel lines, fuel pump, filter, the lot, could stay in place if so preferred. In theory, the car could still be run on the webers, with simply the EFI fuel pump switched off.... (unless of course the venturis will be lifted out of the Webers, which for flow's sake will happen, naturally)
Pic of the motor in a car. This was actually a while ago when I was finishing up the dry sump tank. I would say that part delayed this project a few months. I'd never TIG'd aluminum that thin. I'll take some more pics today. Tank is all finished up but I still need to work out the venting/lid properly. I'm also waiting for a couple of air cleaner elements to show up. I found a couple oval ones from 79-80 Datsun 280z's. I'll be putting the suspension back on the car this week and hopefully get to finally put some load on 'er. She has a real quiet exhaust on 'er right now but the sound of the throttles when I rev 'er is unreal! When I had 'er running on the engine stand it was a little scarey rev'g 'er standing right next to the beast. Now that I have the throttles hooked up to the pedal (which feels sooo smoooothe) I can rev the heck out of 'er. Hopefully be pulling 'er out of the shop this week. cheers Image Unavailable, Please Login
Here's a pic from today ... a bit messy but cleaning up all the plumbing and wiring is really rewarding to me when I'm at the point where the motor lights off instantly and revs so smoothly. The air cleaners will also be a joy to fabricate . The two oval units I mentioned above capture the stacks on each bank perfectly. That secondary catch tank is off my P car ... just used it for mock up ... and I need to take a couple of lb's of material off the oil tank cap. There's a bunch of trick baffling in there for air/oil seperation. The one vent wasn't large enough. cheers Image Unavailable, Please Login
Thanks John! I was going over my finish up list and I might be going for a spin sooner than I thought ... then the fun of tuning the beast will really begin ... glad I don't have to remove jets and stuff to dial 'er in ... that would be really annoying ... you carb guys are really patient especially considering at the end of the day you always leave power on the table . cheers
Air cleaners showed up yesterday. I had a bit of time at the end of the day. Found a scab of material that was perfect for the bases and lids. Pretty much got the lids done ... should have a bit of time to finish the bases today and then it's on with suspension assembly. I just did one of the rear wheel bearings also. Whenever I'm working with aluminum and bearings I heat the aluminum to get the bearing out and in. If the bearings have been in forever getting them out might still take a light tap, but there's nothing like dropping a new bearing in a 200 f aluminum part and "feeling" the aluminum grab the bearing. I've seen a lot of gauled parts from people just using a press. Aluminum is so soft compared to steel. Hopefully next update she's off the lift. cheers Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Okay she's not off the lift, but I had to share this. My mill was all setup to finsih them this morning so I thought WTF ... the day is still young to get the paying jobs out. It is so enjoyable seeing projects like this come together ... some thing are just meant to be . Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
^^I can't find it either!! Nice! You have to shoot a vid of the engine running, I wanna hear it!! This is the same motor that you eventually want to turbocharge, right? Continued success......
Hey guys ... thanks for the positive comments! I'll try and take some today. My flip camera really doesn't have very good sound though. I have another camera that takes digital tape media. The sound on it is really good ... I'll try and dig that out. Plus, my internet connection sucks. If anyone is local and wants to film it and upload I'm okay with that. Hey Pizzaman ... I'm feeling in the Christmas spirit of giving ... you need anything to move your project forward? I'll whip you up something ... just make someone a pizza that's hungry and maybe isn't as lucky as we are ... should probably post that in your thread. I'll PM you if I don't hear from you. I got an extra pair of hands here today. I'll have him clean up the rest of the suspension parts for the beast. BTW ... 328turbo ... this is not the motor I want to turbo. It would be a PITA to plumb it all to the throttle bodies. Here is a pic of my motor I want to turbo and/or contemplating just building another one. I'm coming up on 800 hrs/6 years of run time on this engine. cheers Image Unavailable, Please Login
This is the ITB motor a few years ago! I was going to document the entire process but ... well ... I just figured it'd be another boring engine rebuild thread . Image Unavailable, Please Login
flea bay ... of course! The seller delivered it to me on a rainy day, covered in a blanket ... like it mattered. The heads were still on. I made the puller of all pullers to get the mf'r apart. I'm not sure I'd do it again ... well ... yeah I would if one came along. What is a "good core" trading for these days?
