z-ya Posted September 8, 2007 Author Share Posted September 8, 2007 Haven't done much with them lately. They may end up on the race car along with a Rebello head this winter. If this is the direction I go, I'll post photos and dyno results. Quote Link to comment Share on other sites More sharing options...
Daeron Posted September 8, 2007 Share Posted September 8, 2007 Haven't done much with them lately. They may end up on the race car along with a Rebello head this winter. If this is the direction I go, I'll post photos and dyno results. yuh, the REST of the engine was what I was curious on. I think I am more interested in what they sound like than anything else; all other questions are beyond satisfied in my mind. Quote Link to comment Share on other sites More sharing options...
RacnJsn95 Posted September 13, 2007 Share Posted September 13, 2007 Wow, looks great! Can't wait to hear for it performs! I was making one for my Z when I still had it, but I sold the car. I still have it running around somewhere... Long ago TonyD gave me the idea to use the throttle bodies, and linkage off a Z32, just shorten the linkage down. If I ever find myself a 2 door 510 around here, I'll probably do that. Quote Link to comment Share on other sites More sharing options...
SHADY280 Posted September 15, 2007 Share Posted September 15, 2007 well now i know what to do with my su's i was gonna throw away or sell. and my spare tb's i was storing for something. how did you do the injector bungs? weld on a efi manifold to the flange area? Quote Link to comment Share on other sites More sharing options...
z-ya Posted September 15, 2007 Author Share Posted September 15, 2007 well now i know what to do with my su's i was gonna throw away or sell. and my spare tb's i was storing for something. how did you do the injector bungs? weld on a efi manifold to the flange area? It is basically SU manifolds grafted onto a severed EFI manifold. I cut the EFI manifold just after the injector mounting screw. Quote Link to comment Share on other sites More sharing options...
TABrinn Posted October 27, 2007 Share Posted October 27, 2007 :2thumbs:I've been looking for ideas on how to do do this for some time now. Looks awesome! On mine I want to gut out the SU's and use them as throttle bodies only and have the multiport injection like yours. Would the zxt throttle bodies offer any advantages in performance over hollowed out SU's? How much more power do you speculate your setup will have over the stock EFI? Once again, awesome work! Quote Link to comment Share on other sites More sharing options...
z-ya Posted October 27, 2007 Author Share Posted October 27, 2007 These people are making a conversion kit. They supposedly have a kit in works for the Hitachi SUs. You might want to check with them. http://www.sidedrafttbi.com/index.htm Quote Link to comment Share on other sites More sharing options...
TABrinn Posted October 28, 2007 Share Posted October 28, 2007 Yes, I put up a link to their site in another thread a while back. Which do you think will work better, 2 injectors in each throttle body or the 6 injector direct port injection? From what I understand, having the injectors closer to the port gives better drivability around town and the throttle body injection would be better at higher RPM's. For all out performance you could use both with your ECU programmed to fade out from one to the other over a given RPM. This would provide the fuel more time to vaporize at the higher engine speed. More efficient burn= More power. But for me that might be a little overly complex. I just want my Z to breath as freely as possible without blowing my entire engine budget on the intake alone. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 28, 2007 Share Posted October 28, 2007 These people are making a conversion kit. They supposedly have a kit in works for the Hitachi SUs. You might want to check with them. http://www.sidedrafttbi.com/index.htm Actually, the question has come up on their forums and it's still open-ended if they will fit or not. I have offered to send him 'one of each' so that they may check fittment on the Round-Top 46mm Hitachis, Flat Top 46mm Hitachis, and the smaller 38mm SSS/Roadster Hitachis. No takers as of yet... So if someone wants to actually BUY a set and try them... I would think offerring postage one way to try, and postage back to me would open up a whole new market stream to their product and they would jump at it... Maybe during the winter he will get back to me on e-mail and do it then. Who knows. Quote Link to comment Share on other sites More sharing options...
Daeron Posted October 29, 2007 Share Posted October 29, 2007 I can't see any reason, other than the "stealth" desire, to go for the SU body. Try the TB from an SPFI 80s Subaru: times two. You might need to upgrade the injector in the TB, and I know nothing about possibilities for that, but I don't know... i cannot recall the flow rate on the injector at the moment. I had honestly come across the idea for doing the exact setup Z-ya has done, when he did, FROM having thought and spoken extensively with my uncle, about making a setup for one of his roadsters, using MS, SU manifold, and two subaru throttle bodies. If not the subaru piece, then find one thats more appropriate; there are thousands of TBI cars in the junkyard. Quote Link to comment Share on other sites More sharing options...
TABrinn Posted October 29, 2007 Share Posted October 29, 2007 I can't see any reason, other than the "stealth" desire, to go for the SU body. The biggest reason being that it fits with no modification, and I wouldn't need to fabricate any linkage. Besides just from looking I'd say a hollowed out SU would flow more than that Subaru TB with that big obstruction stuck in its throat. What is that, a MAF sensor? You could do better. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted October 29, 2007 Administrators Share Posted October 29, 2007 Try the TB from an SPFI 80s Subaru: A couple of day's ago I was combing a JY and spotted the same thing. What detracted me from it was the throttle size. I didn't measure it but it struck me as quite small. Quote Link to comment Share on other sites More sharing options...
Daeron Posted October 29, 2007 Share Posted October 29, 2007 The biggest reason being that it fits with no modification, and I wouldn't need to fabricate any linkage. Besides just from looking I'd say a hollowed out SU would flow more than that Subaru TB with that big obstruction stuck in its throat. What is that, a MAF sensor? You could do better. It is the fuel injector. A couple of day's ago I was combing a JY and spotted the same thing. What detracted me from it was the throttle size. I didn't measure it but it struck me as quite small. Well, after posting last night I dug out my FSM and couldn't find a throttle diameter or injector flow rate, but just now I stepped out front and measured it. 60mm opening. It tapers down at the actual throttle plate to something like 40-45, and thats being conservative. Times two, even with the restriction caused by the schnozzle for the injector, I think should be ample, certainly for a roadster (maybe a turbo roadster??) and possibly, use roadster SU manifolds on a Z to use three??? Potentiometer-style TPS fitted, IAC fitted, cable throttle drum...... it wouldn't be difficult to drill up some holes. I will have to look further into the size and shape of the footprint, but... Overall, my point was that through some simple junkyard picking, ideal throttle bodies would probably start to fall in your lap. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted October 29, 2007 Administrators Share Posted October 29, 2007 It tapers down at the actual throttle plate to something like 40-45, and thats being conservative. Hmm.... well, I could be mistaken. I'll check next time I'm out there. That's an EA82 you're looking at correct? Times two Its not that simple. Only one intake valve is open at any given time, so separating the cylinders into two banks and using two TB's, doesn't change much. Adding six, one per cylinder, gains you little. Also, even if the throttle is 45mm, an L28 intake valve is 44mm. While the valve doesn't open completely, and has a stem, don't dismiss the throttle shaft/screws. Its quite restrictive. My point is, even at 45mm its cutting things a little close, in my opinion. I'd like to see about 15-20% more flow through the throttle than the valve. Thats a reasonable compromise between 'enough' and 'too much'. Overall, my point was that through some simple junkyard picking, ideal throttle bodies would probably start to fall in your lap. Point taken... and its a good one at that. Some of the best ideas have sprouted from the JY. Quote Link to comment Share on other sites More sharing options...
TABrinn Posted December 6, 2007 Share Posted December 6, 2007 Any news on the intake? Quote Link to comment Share on other sites More sharing options...
Tony D Posted December 6, 2007 Share Posted December 6, 2007 The Injetor being where it is doesn't affect flow like you would think. Air comes in from the edges of the port, not directly down the center of the hole. It's why full radius horns flow better then straight hole walls. Quote Link to comment Share on other sites More sharing options...
frank280zx Posted December 6, 2007 Share Posted December 6, 2007 haha i have exactly the same thing laying at my workbench lol Quote Link to comment Share on other sites More sharing options...
Daeron Posted December 6, 2007 Share Posted December 6, 2007 haha i have exactly the same thing laying at my workbench lol an SU/EFI hybrid manifold, or a subaru EA82 intake? Back to the greater topic at hand, One could always go with a TBI off a V8 RS camaro, fitted onto a four barrel manifold.. hmm. I am The Junkyard Warrior, aren't I? I just want to see a Datsaru, thats all. One way or another, I want to give my uncle a fuel injected roadster before he leaves us. The old man deserves to have one good, reliable vehicle... He gave my brothers and I so much more than my dad could, just in terms of "room to grow" with cars.. Dad couldn't have the nice shop, with drill presses and a big air compressor and things like that, because he had us to feed.. bah, I am waxing sentimental. Must be past my bedtime, I'll shut up now. I just cant resist ANY temptation to post in this thread Quote Link to comment Share on other sites More sharing options...
TABrinn Posted December 7, 2007 Share Posted December 7, 2007 Did Z-YA make any progress? I didn't meen to start up the jy throttle body debate again. Just want to know how well it runs. Quote Link to comment Share on other sites More sharing options...
z-ya Posted December 7, 2007 Author Share Posted December 7, 2007 I'm still in the process of deciding what motor to put it on (NA, turbo, twin turbo). as soon as I make more progress, I will post it. Quote Link to comment Share on other sites More sharing options...
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