R88RPE Posted September 6, 2015 Share Posted September 6, 2015 (edited) Hello, recently I have been looking at adding some more mid range torque to my GT4 . Im not one to be bouncing off the rev limiter when I drive hard so I feel im not getting the most out of this engine (I would prefer a extra 10tq lower down than a extra 10hp at 7000rpm) With this in mind I have been doing some research into the mrev2 lower plenum (http://www.motordyne...pID=149ℑ=0) which is basically a moddified pre 05 lower plenum. I have been trying so find out what these modifications are and so far I have found out from a few american owners clubs that 5mm is shaved off the two "snouts" to aid airflow to the front two cylinders. Has anyone else done this to a stock revup? and will it make any difference without a remap (im not going to remap until I have exhaust ect fitted in a few months time). I know that the plenum spacers have no effect on the stock revup engine, this has been proven a few times in america but they apparently do make a difference with the pre 05 collector or mrev2 fitted. Is it worth fitting a spacers while im fitting the lower collector? They are sold together here with 'substantial' power gains http://torqen.uk/ps/...pacer&results=9 This is the spacer on its own http://torqen.uk/ps/350z/engine/plenum-spacers/264-350z-de-motordyne-engineering-516-basic-plenum-spacer-md-ps-b.html?search_query=plenum+spacer&results=9 Here is a dyno print out I found with a stock run, with mrev2 and then with mrev2 and spacer. As you can see the car with the mrev2 does have more power through the range until it drops off at 6000rpm, this is where the mrev2 and spacer come in. So basically... can anyone on here confirm that there is some benefit to fitting a modified lower collector or mrev2 to my uprev engine without a remap, and if there is, should I fit a spacer to. Thanks! Edited September 6, 2015 by R88RPE Quote Link to comment Share on other sites More sharing options...
Paddy78 Posted September 6, 2015 Share Posted September 6, 2015 I've got one fitted, but I had mine done at the same time as a spacer, sports cats and remap, so difficult to pinpoint how much this added (if anything). I think you need a spacer to get any benefit from it and probably a remap is required too? Quote Link to comment Share on other sites More sharing options...
KyleR Posted September 6, 2015 Share Posted September 6, 2015 (edited) According to the graph, it'll only gain you about 6 bhp over stock, so for £500+, I wouldn't bother. Edited September 6, 2015 by KyleR Quote Link to comment Share on other sites More sharing options...
R88RPE Posted September 6, 2015 Author Share Posted September 6, 2015 Thanks guys. How much power did you make Paddy? Im planning those mods eventually. Has anyone fitted a pre 05 lower collector to a uprev engine with or without spacer? I have a pre 05 collector sat here, im going to mill 5mm off the first two cylinder snouts as per mrev2 and port and polish it at work. BUT i only want to do this if its beneficial, if its going to have a negative effect I wont bother. Quote Link to comment Share on other sites More sharing options...
Paddy78 Posted September 6, 2015 Share Posted September 6, 2015 Thanks guys. How much power did you make Paddy? Im planning those mods eventually. Has anyone fitted a pre 05 lower collector to a uprev engine with or without spacer? I have a pre 05 collector sat here, im going to mill 5mm off the first two cylinder snouts as per mrev2 and port and polish it at work. BUT i only want to do this if its beneficial, if its going to have a negative effect I wont bother. I made about 283 WHP, which I think is around 310 engine once you minus what you lose from the drive train... I think I also gained about 30 Torque. Not huge numbers, but you can't really make big numbers on an NA Zed. Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted September 6, 2015 Share Posted September 6, 2015 I do not have the exact numbers for you, however, what your are proposing is not cost effective, however shaving 5mm off the two "snouts" to aid airflow to the front two cylinders as a DIY is cost effective. I have done a few and the bench work is circa 1 hour. Quote Link to comment Share on other sites More sharing options...
R88RPE Posted September 6, 2015 Author Share Posted September 6, 2015 (edited) 310bhp are great numbers for a na z I'd be over the moon with those! What exhaust do you have paddy? I haven't had mine on the dyno yet but I'm going to do it before I change anything so I have a rough baseline figure. Zmanalex, did you do this to your own cars? Any noticeable diffences regrading power loss or gain? Edited September 6, 2015 by R88RPE Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted September 6, 2015 Share Posted September 6, 2015 Zmanalex, did you do this to your own cars? Any noticeable diffences regrading power loss or gain? Customer's cars, and all were well happy. Quote Link to comment Share on other sites More sharing options...
R88RPE Posted September 6, 2015 Author Share Posted September 6, 2015 Zmanalex, that's good news! Did you fit them with a spacer or literally just the collector? Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted September 6, 2015 Share Posted September 6, 2015 Some with a 5/16 spacer and some with out. Quote Link to comment Share on other sites More sharing options...
daveallen1999 Posted September 6, 2015 Share Posted September 6, 2015 Hi Zmanalex, I am interested in this. I have send you a PM. Zmanalex, did you do this to your own cars? Any noticeable diffences regrading power loss or gain? Customer's cars, and all were well happy. Quote Link to comment Share on other sites More sharing options...
R88RPE Posted September 6, 2015 Author Share Posted September 6, 2015 I may pm you for some tips on modifying my own then Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted September 7, 2015 Share Posted September 7, 2015 I may pm you for some tips on modifying my own then No need, a lot of info here: https://www.google.co.uk/?gws_rd=ssl#q=modify+350Z+lower+plenum Quote Link to comment Share on other sites More sharing options...
R88RPE Posted September 8, 2015 Author Share Posted September 8, 2015 (edited) I think im going to get a dyno done as standard, then one with the lower collector fitted to see what the gains and losses actually are on a stock revup. Would anyone else be interested in these results? Edited September 8, 2015 by R88RPE 1 Quote Link to comment Share on other sites More sharing options...
d95gas Posted September 8, 2015 Share Posted September 8, 2015 Loads of links but no real specifics on "How-To" for us "novice engineers" Quote Link to comment Share on other sites More sharing options...
R88RPE Posted September 8, 2015 Author Share Posted September 8, 2015 There's a right mixed bag of results to depending on who and what's been done. I'm struggling finding actual facts lol 1 Quote Link to comment Share on other sites More sharing options...
flyboy Posted September 13, 2015 Share Posted September 13, 2015 Loads of links but no real specifics on "How-To" for us "novice engineers" 1.Take it off the car 2.Take a grinder to it. 3.Make it look like the modified one. 4.Put it back on the car That's about it really. Quote Link to comment Share on other sites More sharing options...
MrG13 Posted February 15, 2016 Share Posted February 15, 2016 I think im going to get a dyno done as standard, then one with the lower collector fitted to see what the gains and losses actually are on a stock revup. Would anyone else be interested in these results? did you get around to this? any numbers orr...... Quote Link to comment Share on other sites More sharing options...
fake ben taylor Posted February 15, 2016 Share Posted February 15, 2016 Pre revup lower plenum has different length runners than the revup I believe and its that that gives the differences, shaving the snouts is just a little extra and very easy to diy. I have a spare lower, pm me and ill check which it is and can do the mrev mods for you if you like if its previous and then post if off to you, obvioualy youd have to pay me for the lower though Quote Link to comment Share on other sites More sharing options...
Karl92 Posted February 20, 2016 Share Posted February 20, 2016 (edited) i made 315 on a revup with a motordyne plenum stillen filter berk decats and a miltek system i wouldn't bother with a pre revup lower plenum its not worth the cost karl Edited February 20, 2016 by Karl92 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.