2802NR

thought you on the front range might be interested. http://www.b15sentra.net/gallery/files/1/6/8/8/3/0505catt_new.jpg I can post more info if anyone is interested.

I heard 10.4 with a standard gasket. Anyways, Thats what I am running and I have never had a problem with detonation on 91. Just dont get carried away with your ignition timing and you will be fine on 91 octane. p.s. I am over 4000 ft. Dont know if that makes a huge difference or not. someone want to elaborate on elevation/compression? edit: I am .030 over so I am pushing even more comp than a stock L28.

I have been looking for a custom molding place as well. I need a boot that will fit a chevyTPI TB with a 90deg. bend to a 2.5 in outlet.

The stock ZX Distributor will work fine for a low compression (in comparison) NA motor. Here is a good thread about megasquirt & ignition control that helped me understand alot more: http://forums.hybridz.org/showthread.php?t=106924

I dont know about the worm gremlin. All I know is that Z looks GOOD layin out on those leaves.

bastaad is right. I'm running a .030 over flat top n42 with the stage III 270/280 .460 lift. 3 into 2 header, 2.5 exhaust. On stock FI, I put 169hp and 175ft/lbs tq at 4200ft elevation. needless to say I expected a little more but thats the way it goes sometimes. Anyway, I would bet the two cams will produce different torque curves with very similar max numbers. just my 2 cents.

I'll have a non-egr for sale in about a month or two if you can hold out that long. Its been shaved and powder-coated white. let me know if your interested.

This thread is exactly what I have been searching for. I will also be switching from the stock 77 EFI to MS soon and have been re-searching what I need/dont need. I am running a 10.4-1 CR NA motor and am going to MS and a custom Intake manifold in order to utalize my cams powerband (3K to 7K rpms) for track days & time trials. it is also a daily driver. Here are the questions I have: 1) Tony, when you say "re-curved distributor" do you mean an aftermarket unit like the mallory or can I re-curve or have someone re-curve my stock unit? (stock 77 dist.) 2) I see everyone mentioning the MSD 6A unit. Does the rev limiter on the 6AL cause problems with the MS tach signal? Or are you guys just talking about the 6A family as a whole?? If possible I would like to have a rev limiter which brings me to my next question. 3) Do any of the MS versions have rev limiters? I have read over and over the MSEFI info pages and havnt found anything. this is why I want to use the 6AL unit. 4) Wich MS version would you guys recomend for an NA setup like mine? I was looking into MS2 but if I dont need/wont gain anything from an adjustable ignition map than I would like to keep things simple. Let me re-phrase, I want to keep it simple but i want a setup that will fill all my needs for years to come. I will be making more modifications but i dont plan on ever putting it under boost.

Once everything is finished and on the car I'll have a little under 3 in. between the TB and the drivers side strut tower, but it is mostly behind the tower due to engine placement so I will probly rout it backwards and end up with a filter near the master cyl. which isn't very ideal but my header is ceramic coated so engine bay temps are reasonable. I thought about modifying a Z31T hood scoop if I end up with my filter in this location.

I'm going to use a dual 48mm TB off of a '88 TPI corvette. That way both plenums will be 100% independant of each other. Ill try to get the final cad drawing up once I re-draw it.

Cant wait to see those dyno numbers. just thinking of a stroker at 8k makes my boxers shift.

240turbo, It will be a split plenum design. My computer didnt save my latest cad re-vision but here is an older one I still have: I had to re-draw the head flange for header clearance and I made the plenum volume alot smaller than this version. The plenum also extends 1in. past #1 & #6 for better air supply in the newest version wich I'll have to re-draw again. Thanks for all the input guys!

helix, This wil be used on a 10.4-1 NA motor with a .460 270/280 cam. 1 fast z, The min. I.D. is matched to the head port dia at 1.420 in. and the entrance R is .25 so that ends up at 1.8388 runner entrance I.D. Now I had to use a harmonic pressure wave set of 4 due to limited space in the engine bay. 1.7 degrees may be an extreme amount of taper but it shouldnt inhibit airflow, it may however exceed the limit of what a taper can do to help airflow. Here is the formula I used Wich was the Grape Ape Racing formula taken directly from the intake manifolds chapter of "How to tune & modify engine management systems" by Jeff Hartman: [(ECD * .25 * V * 20)/(RPM * RV)] - (D/2) = L ECD= Effective cam Duration V = Pressure wave speed (speed of sound) RV = Reflective value (the utalized pressure wave set) D = Runner diameter (I wasnt sure on this because of the taper so I used the averege diameter over the given length) L = Runner length [(420 * .25 * 1300 * 2)/(6000 * 4)]-(1.64/2) = L 273,000/24,000 = 11.375 - .82 = 10.555 valve seat to mating surface = 3.511 (the book didnt specify on this so I used the short side radius) 10.555 - 3.511 = 7.044 runner length Now as I said earlier, There were a few variables which the book wasnt too specific on so I used some guess work but it will be interesting to see how it works out bieng my first shot at it.

Unfortunetly the port entrance-to-valve isnt a very accurate taper. I had a local machinist work it and he did a good job on the short-side radius but they ended up at about 1.42 in. entrance I.D. wich isnt very close to the 1.73 in.(is that right? I cant remember off my the top of my head) L28 Intake valve O.D. Anyways, I'm hoping this will increase my power band so I can get the most out of my cam. Right now it prety much falls on its face around 5200 r's. Ill be installing MS2 at the same time so that will help as well.

Got started on my intake manifold friday and I thought I'd post some pics. I still have to mill 4 of them for clearance between #1, #2 and #5, #6 but here are the runners: and some machining pics: The runners are just over 7 inches and are tuned in length using the grape ape racing formula for a helmholtz resonater effect. They have a 1.7 degree tapered bore which matches my mildly ported N42. Ill try to continue posting pics as I fabricate the flanges and plenum.

Thanks for the info about the SU manifolds. I have access to the equip. to make my own manifold so I am going to give it a try. I think I am going to use the dual 48mm??? TB off of an early TPI chevy. I will have an advantage over the SU manifolds though, Longer runners with a 1.5 degree taper.

Hi everyone, New user here. I'm knee deep in the Intake manifold design process and am going through the formulas for proper throttle body size in relation to CFM requirments. I found some very good info at http://msefi.com/viewtopic.php?t=9731 and Im just looking for someone to double check my use of the forumla found there. PLEASE READ THE LINK. It explains all the formulas I use here. If any one else has used this method and find any thing wrong, please corect me. I will be fabricating a dual-plenum design and using a dual bore throttle body so I figured this for half my displacement. 84.5cid * 7,000rpm / 2 = 295,750 cubic inches air per minute @ 100%VE 295,750 / 1728 = 171.15 cubic feet per minute 171.15 / 900 * 9.62 = 1.83 square inches Now I'm unsure on this part, I am suplying 3 cylinders per throttle valve so should I figure an intake stroke 16.6% of the time or an intake stroke 50% of the time? I will be supplying #1,2,3 with one valve and #4,5,6 with one. Just to get an Idea, I figured the rest for 50% with a -5% margin for blow back. (same as the example from msefi.com) 1.83 square in. /.45 = 4.07 square in. Now to convert area to diameter: Area = pi radius squared = 3.1416 r squared = .7854 diameter squared 4.07 / .7854 = 5.18 d squared Square route of 5.18 = 2.28 diameter Now convert inches to mm 2.28 * 25.4 = 58mm Throttle body per 3 cylinders. Now I know My engine will never run 100% VE but I just needed a ball park figure. All suggestions welcome and appreciated!