rturbo 930 Posted January 25, 2023 Share Posted January 25, 2023 2 hours ago, jeffer949 said: Cool to see where this goes. I have my 84 maxima engine apart right now prepping it for turbocharging. It has the L24e in it and has the mn47 head. Looks like there is some low hanging fruit on the head. Will be cool to see what you come up with using your friends software. I was curious how hard it would be to remove the liners. Probably not worth it for my HP goals. (That Im going to stick to and not get greedy) (I promised my wife)(Really!!!) Also. What are your thoughts on the steel liners and boost? I know people have done it but has anybody ever seen any negatives to it? My understanding is that removing the liners ruins the flow of the head since the ports end up being too big. Quote Link to comment Share on other sites More sharing options...
jeffer949 Posted January 26, 2023 Share Posted January 26, 2023 1 hour ago, rturbo 930 said: My understanding is that removing the liners ruins the flow of the head since the ports end up being too big. That was my understanding also. I guess I was thinking this was going to be a break out the tig and weld up the ports type job. I Quote Link to comment Share on other sites More sharing options...
madkaw Posted January 26, 2023 Author Share Posted January 26, 2023 16 hours ago, jeffer949 said: Cool to see where this goes. I have my 84 maxima engine apart right now prepping it for turbocharging. It has the L24e in it and has the mn47 head. Looks like there is some low hanging fruit on the head. Will be cool to see what you come up with using your friends software. I was curious how hard it would be to remove the liners. Probably not worth it for my HP goals. (That Im going to stick to and not get greedy) (I promised my wife)(Really!!!) Also. What are your thoughts on the steel liners and boost? I know people have done it but has anybody ever seen any negatives to it? One of the Maxima heads I have - might be the one on my stroker- was previously on a turbo motor . The later heads seem to be better castings and I think for low boost motors it would be fine . Quote Link to comment Share on other sites More sharing options...
madkaw Posted January 26, 2023 Author Share Posted January 26, 2023 15 hours ago, rturbo 930 said: My understanding is that removing the liners ruins the flow of the head since the ports end up being too big. One of the things I’m hoping to verify . I will be doing a head that has liners removed Quote Link to comment Share on other sites More sharing options...
madkaw Posted January 26, 2023 Author Share Posted January 26, 2023 14 hours ago, jeffer949 said: That was my understanding also. I guess I was thinking this was going to be a break out the tig and weld up the ports type job. I Not sure there is a way to weld the short side radius which is arguably the most important . I had it welded under the seat on the long side - that was tough enough Quote Link to comment Share on other sites More sharing options...
jeffer949 Posted January 26, 2023 Share Posted January 26, 2023 1 minute ago, madkaw said: Not sure there is a way to weld the short side radius which is arguably the most important . I had it welded under the seat on the long side - that was tough enough Understandable. Quote Link to comment Share on other sites More sharing options...
madkaw Posted January 27, 2023 Author Share Posted January 27, 2023 Like to find the limits of the linered exhaust port as far as flow and see what we can do with the liners pulled . My friend Andy is working on some old Volvo heads now that have a worse short side radius on the exhaust valve than what the MN has with liner pulled . He has some interesting ideas to improve the flow to get the flow around the sharp edge of the seat . Id say either subject has not been dealt with any amount of effort . Most just went on to a different head Quote Link to comment Share on other sites More sharing options...
madkaw Posted February 5, 2023 Author Share Posted February 5, 2023 Well about ready to tear things apart again . I need to cut off the mounting flange for the TB so I can get it better angled to the core support . The angle now puts too much bind on the piping leading to the core support . While it’s off I will also weld build the intake manifold flange mounting ears so I don’t have to run step washers . Very difficult to tell if I am installing the step washers correctly and it’s a vacuum leak ready to happen . Also need to church up some of my welding of the plenum . My welds sucked and left pitting that needs addressed . Im going to make all this happen in conjunction with a bigger cam . Want to get a little more duration in order to match cam to intake . I will probably bump compression closer to 11:1 also . I will also address anything that needs to be done to the ports based on finding with the CFD model . I think I can open up the ports a little more , but won’t do that unless the model suggests that. I’m about at the limit now with port size Quote Link to comment Share on other sites More sharing options...
DuffyMahoney Posted February 12, 2023 Share Posted February 12, 2023 Looks awesome! I love that intake. 1 Quote Link to comment Share on other sites More sharing options...
madkaw Posted March 23, 2023 Author Share Posted March 23, 2023 Well I am taking this opportunity to fix my intake flange position for the TB . I had the angle wrong and it made running the piping difficult . Also going to weld build the runner flanges to get rid of the step washers required with the Cannon intake . Doing all this why going with a bigger cam . While the head is out I am going to open up the ports at the neck . Currently intake runners are tapered to 37mm at the head . The head ports taper down to barely 32mm . This is one of the first MN heads I ported . You can’t hog these like some of the other L heads . I have learned after slicing up a head that I can get closer to 35mm at the smallest ID at the neck . I guess I am pleased I did 230 hp with the port pinched this much . I’ve been able to get 34.5mm just before the bowl in some of the other heads I’ve done . One person I sold a head to got 220 hp with a 2.9 running the head I built for him . This is at the tires ! Im also going to smooth out the ports a bit . I opened up the ports at the head opening to 37 - while the head was on the engine . Needless to say not optimum - but I was careful not to get shit in the motor . With it on the bench I can do a better job . Also going to CC the head and possibly do some work in the chamber . I’d like to bump up the CR to 11:1 for the next - more aggressive cam . It will be 565 lift and I believe 290 duration. I never had any detonation issues with the current set up . Once I crack the engine open I will see how the pistons look . I think with the closed chambers and 93 octane I can get away wit more CR . I can always drop some timing if needed or retard the cam timing a bit if it’s too much . Lots to do before driving season ! Quote Link to comment Share on other sites More sharing options...
madkaw Posted July 19, 2023 Author Share Posted July 19, 2023 When I finally got the head on a work bench and measured the intake ports I realized that I left these smaller than other heads . It was necked down to 32mm in most ports . So I opened them up to 35mm - which is the absolute limit based on a head I cut up . I do have Bonks- stage 2 cam on hand which is probably better suited for my intake - but I might try both . I think the Bonk -1 cam would give better numbers based on increasing my port size . I know bigger is not always better - but compared to all out porting on the N42 , my porting is conservative at 35mm. The intake has been welded on once again . Flange is in the right spot and I decided to weld steps on the flange to eliminate the step washers . Of course after all this welding I was skeptical this flange was flat anymore . I took to my friend/machinist/ welder/ CFD modeler/ and put it on his surface plate . It was bad . Because of its odd shape he couldn’t use his milk and had to hand scrap it flat . Andy is true expert at this . It took it little bit of time but he got it flat . It’s almost an art form . I also had him flatten out my flanges in my exhaust . I couldn’t get it to seal right and my attempts were sad - lol. Quote Link to comment Share on other sites More sharing options...
madkaw Posted August 28, 2023 Author Share Posted August 28, 2023 The latest . There was no signs of trouble before I found this . I was changing out cams and doing more port work when someone noticed in a pic that I had 1&3 pistons swapped - dumb ass . Look liked my front seal was leaking so I went to change that and it took my a half day to get the damper off . Decided to put some fresh rings in and found a broken ring in #6 . So here we go with a complete rebuild . The bearings had some wear and it might be from dirty air being sucked in the chambers . 4500 miles total on this I had done lots of timing changes with as much as 37 degrees total at WOT - probably too much . I drive this engine hard . Rebello told me I should have left the slinger off . Also to make sure I get 150lbs on the damper . Hope I can order 1 pistons - though mine are custom- ugh. Not sure this change the way I drive it but I will be better about the areas I messed up Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted August 28, 2023 Share Posted August 28, 2023 (edited) As a Nissan/toyota/lexus dealership technician who's seen every possible assembly mistake (mostly by fellow coworkers), I'm wondering if the loose main bolts were the result of hydrolocking of the bolts while torquing the main bearing caps. "Hydrolocking" of RTV or grease or assembly lube will give you those satisfying clicks on the torque wrench and then "bleed down"..........especially when the engine is run. Might take minutes or weeks. I'm not implying you guys are sloppy like the work I witness daily. Quite the opposite. I've spent the last 5 years doing what toyota calls "Special service campaigns" on Toyota 86/scion FRS flat four FA20 engine and it seems to be the car that separates the guys who post big hours doing brakes all day from the guys who can assemble an engine correctly. I've even seen more than 10 cars where the flat rate guys smear "FIPG" (toyota's RTV) all over the valve cover gaskets and get some into the bolt holes. Once they tighten down the valve cover bolts or cam housing bolts, enough pressure is generated to blow out where the hole ends leaving quarter sized 10mm wedge shaped chunks of cylinder head that eventually find their way to between the cam and a cam following cup. It only takes a little bit of oil to cause disaster. I've also seen it happen on crank bolts so I'm now off to repost this there. Edited August 28, 2023 by HowlerMonkey Quote Link to comment Share on other sites More sharing options...
madkaw Posted August 28, 2023 Author Share Posted August 28, 2023 I’m sorry but I didn’t say anything about loose main bolts - only the crank bolt Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted August 29, 2023 Share Posted August 29, 2023 got my threads mixed up.............replace "mains" with "crank bolt". On the VG30, some dealership guys snapped the nose of the crank off and was wondering why oil sprayed out. Quote Link to comment Share on other sites More sharing options...
madkaw Posted September 13, 2023 Author Share Posted September 13, 2023 Some good news ! Rebello will be able to come up with one piston for me ! BHJ Dynamics replaced my damper for free ! Their own investigation of the damper showed too tight of a tolerance for the press fit . That caused the initial galling and it got worse over time . I went ahead and purchased their installer to help make sure I get it installed properly . Really happy with Chris at BHJ - he stood by his product . Maybe should have done this earlier but I will be using the head cooling mod on 5&6 cylinders . Also going to be more conservative with my timing . Also installing a knock sensor - but this is a N42 block and had to come up with a location for it . This will take some serious calibration to make it work - if it will work in this location . I had the module already installed on my MS3 . This is a Bosch sensor Quote Link to comment Share on other sites More sharing options...
madkaw Posted January 22 Author Share Posted January 22 Well it’s a new year so time for a new intake - lol. I have issues with my intake so instead of fixing them right now I decided to take the easy route and buy a Protunerz intake set up. Pretty nice piece. Not many options for aftermarket intakes for our motors and glad to see they put this one together . Only found one issue with a misaligned hole that holds the IAC in place . I just altered the mounting hole on the IAC . Of course nothing is just bolt on . I have to change some fuel line placement and vacuum lines and also the CAI piping . Pretty easy stuff since I was running a similar intake . I watched a couple of you tube videos that different guys made of their install - it was painful to watch . They shouldn’t be making any How To videos and they didn’t make PROTUNERZ’s look good . I like what they did with the throttle body . There’s a port for the IAT and IAC . The plenum has a PCV port on the underside! As well as the 4 vacuum ports up top . I think the price is good for all 3 pieces - plenum, fuel rail , TB and all the hardware and fittings Quote Link to comment Share on other sites More sharing options...
Zetsaz Posted January 23 Share Posted January 23 What was painful to watch about the videos? I feel like this intake is not that much different from installing a different oem one. Only thing you have to change is where some vacuum is going to. Well, I guess other than the cable throttle needing to be installed. Quote Link to comment Share on other sites More sharing options...
calZ Posted January 23 Share Posted January 23 What were the issues you ran into with your intake? Quote Link to comment Share on other sites More sharing options...
madkaw Posted January 23 Author Share Posted January 23 13 hours ago, Zetsaz said: What was painful to watch about the videos? I feel like this intake is not that much different from installing a different oem one. Only thing you have to change is where some vacuum is going to. Well, I guess other than the cable throttle needing to be installed. Well like this video saying “issues with new manifold “ . I don’t see issues for a manifold that is NOT advertised as an exact OEM replacement . There are some other videos . Quote Link to comment Share on other sites More sharing options...
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