EMWHYR0HEN Posted February 23, 2006 Share Posted February 23, 2006 i've read up on some online posts about people w/rb25det's swapping the stock over the cylinder head type intake manifold for an rb26dett one w/ ITB's . However, those guys are tossing the ITB's and i guess run the large Q45 Trottle body. I understand that the manifold doesnt bolt right up, and does require some modification to bolt up to an RB25 head. But, no one really went into detail about how much modding there is as far as coolant lines, fuel rail, and that stuff goes. What I plan to do is use the RB26 ITB's possibly without the plenum, and just with some air horns attached to them. (My current engine is an RB25DE). if i do decide to toss the plenum, i'd have to go with a MAP sensor setup right? because i'm also getting rid of the MAF. My question is, what's required to run a MAP sensor setup? Standalone? or is there a way to modify my stock ECU fo that setup? feedback? and by the way is there anyone whos already done this swap that has rb26 ITB's laying around and wants to sell? Quote Link to comment Share on other sites More sharing options...
240Z_Master Posted February 23, 2006 Share Posted February 23, 2006 i've read up on some online posts about people w/rb25det's swapping the stock over the cylinder head type intake manifold for an rb26dett one w/ ITB's . However' date=' those guys are tossing the ITB's and i guess run the large Q45 Trottle body. I understand that the manifold doesnt bolt right up, and does require some modification to bolt up to an RB25 head. But, no one really went into detail about how much modding there is as far as coolant lines, fuel rail, and that stuff goes. What I plan to do is use the RB26 ITB's possibly without the plenum, and just with some air horns attached to them. (My current engine is an RB25DE). if i do decide to toss the plenum, i'd have to go with a MAP sensor setup right? because i'm also getting rid of the MAF. My question is, what's required to run a MAP sensor setup? Standalone? or is there a way to modify my stock ECU fo that setup? feedback? and by the way is there anyone whos already done this swap that has rb26 ITB's laying around and wants to sell? [/quote'] You can run a Power FC J-Jetro (which uses MAP sensors). The standard D-Jetro systems run off of MAF sensors. You can also use a standalone, but make sure the stand alone works with the 6 coil packs which is a problem for some standalones unless you use the coil packs that the standalone provides, which to me defeats the purpose of having stock coil packs. Also, there have been people that made adapter plates for the RB26DETT manifold and ITB's, but I have yet to know who can make one. Maybe we should give Pete a call! Quote Link to comment Share on other sites More sharing options...
cheftrd Posted February 24, 2006 Share Posted February 24, 2006 The easiest, least expensive way I've found to do it is with SDS efi. If you get the 6F system, and order it to drive the MSD DIS4, you can use the stock coils. By deleting the coils that come with the system and not having to buy quality plug cords, the price comes out to about the same, including the DIS, as the standard F system. Plus you end up with a high-power ignition system. Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted February 24, 2006 Author Share Posted February 24, 2006 The easiest, least expensive way I've found to do it is with SDS efi. If you get the 6F system, and order it to drive the MSD DIS4, you can use the stock coils. By deleting the coils that come with the system and not having to buy quality plug cords, the price comes out to about the same, including the DIS, as the standard F system. Plus you end up with a high-power ignition system. Sorry to be such a kook in this subject, but can someone explain to me how an SDS system works? would i be getting rid of my entire stock engine harness? would the sds system still be able to manage the VTC, TPS, Air Reg. , idle control, and other stock equiptment? another question is what other components are needed for an SDS? Quote Link to comment Share on other sites More sharing options...
cheftrd Posted February 24, 2006 Share Posted February 24, 2006 Sorry to be such a kook in this subject' date=' but can someone explain to me how an SDS system works? would i be getting rid of my entire stock engine harness? would the sds system still be able to manage the VTC, TPS, Air Reg. , idle control, and other stock equiptment? another question is what other components are needed for an SDS?[/quote'] SDS is stand alone engine management. It has an RPM switching capability that will control Nissan single stage variable valve timing, VTEC on Hondas, etc. It also has idle control for warm up, AC, etc. As it is stand alone, it requires the TPS to work. Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted February 24, 2006 Author Share Posted February 24, 2006 SDS is stand alone engine management. It has an RPM switching capability that will control Nissan single stage variable valve timing, VTEC on Hondas, etc. It also has idle control for warm up, AC, etc. As it is stand alone, it requires the TPS to work. sweet, thanks chef. Hey Q, who's Dave, and what does he do? Quote Link to comment Share on other sites More sharing options...
alexideways Posted February 28, 2006 Share Posted February 28, 2006 What I plan to do is use the RB26 ITB's possibly without the plenum' date=' and just with some air horns attached to them. [/quote'] Hi, don't whant to look stupid but, how will the Manifold Absolute pressure sensor work if the throttles are'nt connected to anything. Quote Link to comment Share on other sites More sharing options...
240Z_Master Posted February 28, 2006 Share Posted February 28, 2006 Hi, don't whant to look stupid but, how will the Manifold Absolute p[/u']ressure sensor work if the throttles are'nt connected to anything. There should be vacuum ports that it can read off of after the horns. Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted February 28, 2006 Author Share Posted February 28, 2006 Hi, don't whant to look stupid but, how will the Manifold Absolute p[/u']ressure sensor work if the throttles are'nt connected to anything. I dont think the MAP sensor has to read pressure from all six inlets (on ITB's), but what 240zmaster said is correct. Quote Link to comment Share on other sites More sharing options...
240Z_Master Posted February 28, 2006 Share Posted February 28, 2006 Okay, so I was tinkering around my friend's shop some more today and realized a couple things that I didn't remember before. The plenum bolts onto the ITB's, and the ITB's bolt onto another manifold, and that thin manifold bolts onto the head. Now the piece that needs to be made, is the piece between the ITB's and the head. It's basically going to have to be a two sided adapter, one that works with the RB25 head, and the other face for the ITB's to bolt up to. Also what makes this more complicated is the water ports that go between each pair of intake runners. Quote Link to comment Share on other sites More sharing options...
Ed260Z Posted February 28, 2006 Share Posted February 28, 2006 It seems like a lot of work to go through for not much more gain in performance. But I guess it depends what your going to use the car for. ITB's are great for auto-cross type events, and the TB is great for Drag. Either way there is not much of a difference, until you start making Mega HP. Quote Link to comment Share on other sites More sharing options...
240Z_Master Posted February 28, 2006 Share Posted February 28, 2006 It seems like a lot of work to go through for not much more gain in performance. But I guess it depends what your going to use the car for. ITB's are great for auto-cross type events, and the TB is great for Drag. Either way there is not much of a difference, until you start making Mega HP. Honestly, I don't care with either ITB's or Huge TB. My main goal is to do this because on the GReddy intake plenum on the RB25DET, with the Q45 throttle body on it, the throttle goes almost right up to the fenderwall (due to it's angle). The RB26DETT's plenum is pointed forward a little bit more (less angled), and is not as wide (as the GReddy manifold) allowing more room between the fenderwall and the plenum. By allowing the use of the RB26 style plenum/ITB's, it will free up more room in the engine bay. Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted March 1, 2006 Author Share Posted March 1, 2006 Unless your aiming towards BIG amounts of power, like 900+, then I think the RB26 manifold setup is more suitable compared to the greddy. Heck, it might even end up being cheaper to go with the RB manifold. plus, like Q said, more room for the engine bay. Additionally, ITB's in almost any application = good throttle response. so Q, know anyone who can Fab up an adapter?! Quote Link to comment Share on other sites More sharing options...
alexideways Posted March 1, 2006 Share Posted March 1, 2006 My main goal is to do this because on the GReddy intake plenum on the RB25DET' date=' with the Q45 throttle body on it, the throttle goes almost right up to the fenderwall (due to it's angle). The RB26DETT's plenum is pointed forward a little bit more (less angled), and is not as wide (as the GReddy manifold) allowing more room between the fenderwall and the plenum.[/quote'] Would'nt it be easier to just cut or have cut your greedy rb25 TB flange, rotate it until you get a more favorable placement and weld it back in place. No extra material involved, very low fabrication costs and a proven desing. Quote Link to comment Share on other sites More sharing options...
240Z_Master Posted March 1, 2006 Share Posted March 1, 2006 Would'nt it be easier to just cut or have cut your greedy rb25 TB flange' date=' rotate it until you get a more favorable placement and weld it back in place. No extra material involved, very low fabrication costs and a proven desing.[/quote'] The GReddy intake manifold uses the Q45 throttle body, and nothing else. I don't know about you, but I wouldn't want to cut up a $600 dollar manifold and weld somethign back on. For $600 I would just build me a new manifold. Also, I don't mind the Q45 throttle body, I made some mods and it fits pretty good for me now. (STILL IN SKUNKWORKS) Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted March 1, 2006 Author Share Posted March 1, 2006 Hey Q, what clearence issues are you talking about? it looks perfect to me?! or it close enough where it might hit the body if the engine twists under load? I agree with you on not cutting a greddy manifold though..... rather sell it, and make a custom one. if you do decide to sell it, and i consider buying it from you, can i still use my stock TB on the greddy? or if i have to use a Q45, think thats just too much for an N/A application? or even a better question, is that manifold specifically for TURBO application? Quote Link to comment Share on other sites More sharing options...
240Z_Master Posted March 1, 2006 Share Posted March 1, 2006 Hey Q' date=' what clearence issues are you talking about? it looks perfect to me?! or it close enough where it might hit the body if the engine twists under load? I agree with you on not cutting a greddy manifold though.....rather sell it, and make a custom one. if you do decide to sell it, and i consider buying it from you, can i still use my stock TB on the greddy? or if i have to use a Q45, think thats just too much for an N/A application? or even a better question, is that manifold specifically for TURBO application?[/quote'] I think the manifold works on RB20/RB25, However I do like my manifold and am going to use the hell out of it! Haha. Quote Link to comment Share on other sites More sharing options...
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