Fineline Posted October 12, 2008 Report Share Posted October 12, 2008 Those look good. If your looking for injectors try the rx-7s at the J/Y. They came with large sizes (I have 460cc rx-7 injectors) and are fairly easy to find. Send them out and they can be rebuilt for $25ea. or so. If your going n/a you probably wont need that big of injectors anyway. Start reading the megasquirt website now and the transition wont be as painful. If you need any help with it drop me a line. Quote Link to comment
datzenmike Posted October 12, 2008 Report Share Posted October 12, 2008 (edited) The TBI intake at the beginning of this thread allows adjacent cylinders to draw through the same throttle. The intake is the same as ignition 1,3,4,2. OR as the as the TBI might see it 3,4,2,1. 3 would draw followed 180 later by 4 then 2 followed 180 later by 1. This means that every time #1 intake valve opens the previous intake valve (#2) is still open for another 68 degrees! Likewise when #4 opens #3 is still open for another 68 degrees The cross over manifold would pair cylinder #1 with cylinder #4 which is 360 crank degrees away from an intake. #1 and #4 won't fight each other, same as with #3 and #2. Edited October 12, 2008 by datzenmike Quote Link to comment
510rob Posted October 12, 2008 Report Share Posted October 12, 2008 (edited) disclaimer - don't call me a hater, I am merely playing devil's advocate here... You bought a single sidedraft manifold designed to accept a DCOE/DHLA/PHH pattern carb, but you are planning to buy a single downdraft throttle body designed to replace an IDF/DRLA carb?!? I don't know that a IDF fits onto the pattern for a DCOE - better find that out before you buy a problem instead of a solution. MS will run a pair of injectors just fine (current generation MS systems only have two injector drive circuits anyway, so there's no harm there), certainly you need to calculate the required fueling, but there again, no real problems... Seems like a fair plan to me, but I wouldn't do it myself. Then again, some people don't think I do anything already - why let them down! EDIT - make you own manifold. It's easy. All you gotta do is just... Edited October 13, 2008 by 510rob cause I'm a prick Quote Link to comment
Cuts metal like mad Posted October 13, 2008 Report Share Posted October 13, 2008 YES! Now we're talkin, that manifold will definately sort out the 2 vs 4 injector issue. The z22 crank bolts in... but you will need different pistons to use it, I don't have my book in front of me to check rod lengths but I'll let you do your own leg work there... heres the link; http://www.ozdat.com/ozdatonline/enginedesign/ Its about 95% accurate... but it'll get you close enough since your not building a race motor here. As far as injectors, I would wager a guess here but for fuel economy over HP I wouldn't use anything bigger than a 310cc injector... and that would supply all the fuel an NA L motor could use even up to 2.4 liters... with the lynx mani it would work out great! Quote Link to comment
Orange620 Posted October 13, 2008 Author Report Share Posted October 13, 2008 (edited) disclaimer - don't call me a hater, I am merely playing devil's advocate here... You bought a single sidedraft manifold designed to accept a DCOE/DHLA/PHH pattern carb, but you are planning to buy a single downdraft throttle body designed to replace an IDF/DRLA carb?!? I don't know that a IDF fits onto the pattern for a DCOE - better find that out before you buy a problem instead of a solution. EDIT - make you own manifold. It's easy. All you gotta do is just... I do really appreciate the specific constructive criticism. I hadn't considered whether the IDF and DCOE had the same base pattern. I did a quick search though and found this throttle body base plate which says it fits both patterns, so I have to infer the Lynx will also. http://www.extrudabody.biz/servlet/the-133/Base-Plate--dsh--45mm/Detail I also came across this, made for L20s on the same website. Nice but not cheap. http://www.extrudabody.biz/servlet/the-225/Kit-cln--Datsun-L20B%2C-L18%2C/Detail This one looks like a real good deal but it would have the same overlap problem. http://www.extrudabody.biz/servlet/the-135/Twin-SU-SU%27s-MGB/Detail Edited October 13, 2008 by Orange620 Quote Link to comment
Icehouse Posted October 13, 2008 Report Share Posted October 13, 2008 Mike I forgot to tell you I finally remembered to look at my ECU on my KA, its an 11 write that down so I don't forget!! :D Talking about EFI reminded me. All you gotta do is just... Haha some how I knew you were going to say that :D Quote Link to comment
datzenmike Posted October 13, 2008 Report Share Posted October 13, 2008 Thank you Jeff. I thought it would be a 15 digit number... that's easy enough. Thanks again. (now where's Beebani???) Quote Link to comment
Llittle_Llama Posted October 14, 2008 Report Share Posted October 14, 2008 wow...that last manifold you have listed is NICE!!!! i want, i want.... Quote Link to comment
whisper3H Posted October 14, 2008 Report Share Posted October 14, 2008 I'm looking at using a single Weber DCOE type manifold with a throttle body injector on on L20 in a 620. Does anyone have experience with a DCOE or equivalent sidedraft Mikuni in a 620? Will it fit in there with the brake booster and master cylinder? i say go with American carbs.... i made an adapter plate on my car to mount a Holley 2 barrel carb off a '77 Vega wagon... Quote Link to comment
Orange620 Posted October 14, 2008 Author Report Share Posted October 14, 2008 (edited) wow...that last manifold you have listed is NICE!!!! i want, i want.... Their throttle body looks like its more compact than the CB Performance one and would clear the 620 Master cylinder better. You can get it with different bore sizes too. http://www.extrudabody.biz/servlet/the-90/2-dsh-ITB-dsh-KIT-dsh-40-fdsh-45mm-or-Single-DCOE-fdsh-IDF/Detail Edited October 14, 2008 by Orange620 Quote Link to comment
BarryA Posted October 15, 2008 Report Share Posted October 15, 2008 Weber replacement downdraft 2 bbl / 2 injector TBI unit available. We were at a vintage BMW event in LA over the weekend, and looked at the unit in their vendor booth - should be a relatively easy way to set up a basic EFI system on an engine where retrofitting injection from a later version of the same basic engine design isn't a viable option. Quote Link to comment
Z-train Posted October 15, 2008 Report Share Posted October 15, 2008 i say go with American carbs.... i made an adapter plate on my car to mount a Holley 2 barrel carb off a '77 Vega wagon... That Holley can't hold a candle to a Webber 32/36. Quote Link to comment
Z-train Posted October 15, 2008 Report Share Posted October 15, 2008 Their throttle body looks like its more compact than the CB Performance one and would clear the 620 Master cylinder better. You can get it with different bore sizes too. http://www.extrudabody.biz/servlet/the-90/2-dsh-ITB-dsh-KIT-dsh-40-fdsh-45mm-or-Single-DCOE-fdsh-IDF/Detail What's stopping you from welding injector bungs on a manifold and then using a Megasquirt with a TB.Keep in mind a TBI system is just glorified computer controlled carb. The comparison to American V-8s doesn't fly as there is a plenum involved which changes the whole equation. Quote Link to comment
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