blake culp

mine used to do that for two reasons, first when the cpu plugs were dirty they caused all kinds of bad stuff to happen, i seriously had to floor it to get over a speed bump. Clean them first! Second after a long drive (2+ hrs) it would bog and stall when boosting, i never solved the problem but i believe it to be that my fuel cap is not venting correctly and it causes a vaccume in my tank so the pump couldnt provide enough pressure under boost, thus low fuel pressure. The reason i say i never solved the problem is becaus i went megasquirt and i havnt driven it for that long yet, although im sure it would make it as long as i stopped and took my fuel cap off ever couple hours. But if you want my opinion, get rid of all the stock ecu stuff and all that corrosion and put in a megasquirt, megasquirt is the way to go mobys write up works perfect, i love mine. Blake

i ran a turbo on a N/A block and head thus a N/A cam as well. I did have the turbo ecu and everything that went with it (afm, dist, manifold etc.) and the thing ran like a bat out of he%%, Proabbly because of the higher compression ratio. I would still be running that today but my granger style boost controller stuck and i blew it up,(every cylinder on the head cylinder gasket had blown!!) after you let it sit for a couple months you should take it easy on it before you hammer on the gas in fourth, lol but its my second driver and "experimental" car so that wasnt a big deal to me. But yeah, it might not be ideal but it will work. Blake

i second moby, a laptop shouldnt cost you more than 50$, anything that will boot windows will run megatune. The megatune program iteslf has very low cpu requirements. Furthermore, withoug a wideband you really have no idea what is going on with your motor. I tried to tune mine for a bit witout a wideband and trust me, its near impossible if not impossible. The laptop that it takes to run megatune is so old that many people have them sitting in closets and will just give them away, ask all your friends. Buy the cheapest laptop you can find and then get a lc1.

Wow, thats pretty quick. Especially with a 2.2 60' time. Thats about the same 60 i was running back when i had the stock ecu and turbo and mid 14's (82zxt though). Now im running megasquirt and a t3/t4 and havnt yet got it to the track. People have always told me that for every tenth you shave off your 60' you make up two tenths in the 1/4. Work on your launch and im sure you will break into the 12's. I cant wait to see the video!! One last thing, do you think you could send me pictures of your fuel and spark tables? we have very similar setups and i have mine running well, but i would still like to see some tables from someone who has actually ran their car. Im running MSnS extra, so im not sure if your whole msq would transfer over....but pictures would be great. Thanks Blake

Now that im thinking about it, i think it used to boost a lot better in first before i installed my blow off vavle, its a cheapie... ive been doing so much to my car lately so its kind of hard to remember how it ran before/after the blow off valve. Im going to tighten that up and see what happens. Ive been searching about blow off vavles leaking, and it seems like it is a fairly common problem...

Cygnusx, I am running the stock 3.54 turbo gears with the nissan tranny, but 1st is pretty slow im definately not blazing through it smoking the tires the whole way. 2nd gear ill get full boost but its pretty late, around 4000 and third is a monster pulling hard all the way from 3000 to readline. 240zturbo, Are you asking if i have one (electonic wastegate controller) or if thats what i would hook up to the atmosphere port on the wastegate.....no i dont have one but that is one way i could apply pressure to the atmosphere side of my wastegate, i just dont really want to spend a lot more money on it right now. The t3/t4, Tial, megasquirt, injectors, IC, and TB kinda broke the bank.

im running an external tial 38mm, it was expensive enough it better not be leaking.... but i have read about finding some way to pressure the the atmosphere side of it with 4 or 5 psi to help it stay shut untill it gets to the 12 i have it set at now. thing is im not sure how to go about regulating the atmosphere side to only 4 or 5 psi

My question is who out there can get full boost in 1st gear with a larger than stock turbo? Im running a t3/t4 with a 50 trim and a stage 3 exhaust housing and i can only get around 7-8psi in first gear, the tires are not spinning. Im running megasquirt and i think it might be a tuning issue because it seems really laggy. This cant be normal can it?

You could try shaving it, and then putting in the tower shims. But without putting in the longer valves you get different wipe patterns on the rocker arms and loose some lift because the cam is now farther away from the rocker arm by whatever thickness your shims are. but if you have a spare head....youre not really losing much if it doesnt work out, right? If you have a garage and an engine puller it might be easier to just find a NA motor with flat tops (i got one for free a while back), put the unshaved p90 on it and then you would have a solid, un-molested/shimmed setup running at the stock NA compression ratio. My furst turbo setup i ran a turbo on a NA block and head, Made it about 6 months before i blew it up (stuck wastegate/boost controler....kaboom) but it was a blast to drive with a lot more off boost power. The motor i have in my car now is a complete turbo block and head and you can definatley tell its slower off the line, kinda sad to take a step down.

Easy there killer, before you go shaving your head you need to remember that the cam is up there. What im getting at is you are going to have slack in your timing chain, not a good thing. Im not sure how much you are going to shave off but if you are wanting to up the compression im guessing you are going to shave a fair amount. However if you want to get crazy with it, you can shave your head .08in then shim the towers back up .08in and install valves .08in longer All that is good for just over a point of compression and stock chain tension and stock valve train geometry. Its a pretty big pain in the a@@ but its a trick lots of NA z guys use to increase their compression. I actually did the shave and it worked well, but that was way back before i saw the light and went turbo. I believe the complete write up on how to do the head shave with the tower shims and longer valves is on brian littles zcar garage web page.

I am running the stock one, according to my guage it runs at 30psi at idle i believe it is 32 at 0 manifold pressure. Im not sure of the technical name for the stock regulator, but the stock regulators are referenced to the manifold. The stock regulator will increase pressure evenly with the boost at a 1 to 1 ratio. For example, at 12psi of boost the fuel pressure on the rail will be 44, 32psi base plus 12psi to overcome the 12psi you are boosting. make sense? Im sure the turbo dodge regulator does the same, just with a higher 55psi base setting so at 12psi of boost your fuel rail would be at 67. I am running dsm 450cc injectors so i dont need the higher base pressure to get more flow from them, kind of overkill to begin with. However if you are planning on running smaller injectors you might want to use the 55psi regulator to allow them to flow a bit more fuel, although im sure there is a limit to how much pressure you can put on them. I always heard that FMU's were a "band aid" fix, im sure they do the job good enough, but if you are running megasquirt you are actually fixing the problem.

I have my target AFR tables set, and the megasquirt seems to be using them with no problem but how exactally do i set my VE table so it matches my target table. The way it is running now on just the target tables i would always have to have the wideband on the car, and if the wideband went bad im sure some bad things would happen to my motor. Thanks, Blake

olie, i have no idea how to tune for nitrous from what i understand with a wet kit the nitrous to fuel mixture is done by the "pills" that which are in the nitrous and fuel lines themself so by the time the fuel and nitrous gets to the jet it is sprayed in the correct proportions. Im sure you would tune with a wideband 02 sensor, keep it rich, and retard a few degrees timing. I dont know much about dry systems, mainly because i always heard wet systems were somewhat safer so thats what i planned on installing. Im really hoping that someone who has put nitrous on a turbo car will chime in with some knowledge from expierence. Len, i think i was burning out the hei's because of a bad ground or over heating, i went through three of them. (gotta love autozones lifetime warranty though, lol) This last one i ran a extra wire for an even better ground and bolted the thing to my fender well with a lot of "heat paste" seems to have done the trick. I am actually running the older megasquirt its a version 2.2 but the code i have downloaded to the ecu itself is the most recent. Mega squirt and spark is the old code, im running mega squirt and spark EXTRA. Im pretty sure once we meet up either at your place or the drag strip youre going to be hooked on MS, the install is so clean, and ultimately adjustable. The 300zx ecu may keep you happy for a while, but what happens when you max that system out...however, im not sure what the 300zx ecu is capable of.

Len, yes i got all the electrical gremlins solved. Well i think so anyway as i havnt burnt out my gm hei in say the 200miles i have put on it tuning, where before i was frying them in less than 20miles. The megasquirt n spark extra code that i am using already has provisions for nitrous. There are some mods needed to be made to the MS box itself but they seem pretty minimal. It is all described here http://megasquirt.sourceforge.net/extra/nitrous.html But as i understand it, i can switch to a whole seperate timing table (slightly retard the timing) or retard the timing by a set amount without switching to a new table when the nos is activated. i can even run a seperate fuel table, but i plan on using a wet system so i wouldnt use this feature. Furthermore i can have the nitrous system turned on (simple toggle switch) and activate it by a WOT switch but, the MS will only allow it to spray between two set MAP values. So what i am thinking is to have it turn on at say 85kpa (~-2psi) and turn off at 160kpa (~9psi) and run 12psi-15psi of boost with the turbo alone. When driving all i would have to do is open the bottle, throw the toggle switch, and floor it. MS takes care of the actual activation of the nitrous and fuel solenoids. Depending on how i have it set up i would really only use it for a second or two in first gear at the track... maybe a fraction of a second after each shift, i should be able to keep the turbo spooled and the psi up by shifting quick and my blow off valve. Another thing that i think is really cool about this feature is that the timing will be completly normal untill the nitrous is actually spraying, The instant MS sprays the nitrous it will also switch tables/retard by set amount. This would keep daily driving the exact same as before, as opposed to sluggish daily driving with the timing pulled a set 5-10 deg just in case you want to use the nitrous, that make sense? I know the idea of using nirtous to spool a large turbo has been around for a while, but it would be nice if someone has done it using the megasqurit ecu to trigger the nitrous i have been searching msefi and yet to find much info from people actually doing the mod. I like staying more on the cutting edge, not the bleeding edge.

This is still in the early, early, planning stages but i was reading about how you can set megasquirt n spark extra to trigger a nitrous system between x and y map values in order to spool the turbo faster. Anyone have any info or expierence on this? Im running a t3/t4 50lb comp and stage 3 turbine with a 360deg thrust washer so im pretty sure it can put out all the power i want on the top end, but it seems kind of laggy down low. I am still tuning my MSNS-E so im sure that will get rid of some of my lag, at the same time i have always been intrigued by nitrous. thanks, Blake

I own a zx, i think it will be close in all z's but the zx has a different (shorter) steering shaft making it an even closer fit.

I want to offer one word of caution from my own expierence. If you make a spacer like Cjarloz has pictured it will be very close or will not work on a zx. I made one identical to the one he has pictured and it put the turbo right on the steering shaft. I tried bringing the turbo up by angling the spacer, but never could get it to fit. I made mine out of three inch wide steel stock with i think 3/8 inch spacers. The steering shaft is much longer on z's which gives them less of an angle, where zx's are shorter and have more of an angle bringing them closer to the turbo. Im not trying to say it can't be done, but its going to be a close fit and it was a huge pain in the a@@, so much that i just welded my tial on the manifold.

It just died again, completly out of the blue. i was running fine, tuning it with my wideband and i pull into a parking lot to tinker with the ve table and while it is idling it died. no warning, nothing. Here is what i know so far, the ms seems to be grounding out the signal wire to the hei. I tested it by a LED and it wont turn on when the car is in the on position or flicker when cranking. the wire is getting power because i tested on the 5v side of the pullup resistor from the tps 5v vref and the light turns on. So for some reason my MS is always grounding the wire, instead of grounding it only when it should be firing. im really thinking about doing the led17 for ignition signal, but im not positive that would solve my problems. Any ideas? Im running ms1 v2.2 with the newest release of msnsE.

I didnt really think anyone would live close enough or have a free day to spend tuning, but i thought it was worth a shot, plus they could look over my setup and see if i had any obvious mistakes because this is my first shot at running any kind of aftermarket ecu. I just ordered the lc-1 for 200$, that was after calling all the dynos and finding out that a pull is 40$ not bad, but to use their wideband it is considered tuning and thats a minimum of 120$. I think ill be money ahead with the wideband.

I live in the okc area and i have my car running on msns, but im not really sure how to tune it. If anyone in the okc area has a wideband and would like to spend a day helping me tune my car i would definately make it worth your time. thanks Blake

thanks for all the replys, im still not really sure what happened, i tried to send msns extra to my ecu through easytherm and it did it successfully, but my after i changed my megatune in the settings to msns extra it wouldnt open... Not really sure why because i have the newest version of megatune 225, but anyway, i reloaded regualr msns, manually went through all my vetable, sparktable, constants etc. (didnt use any saved data, period) and it started. All i can think of is if the msq. from mobly for the 450cc injectors i sent to the ms ecu some how corrupted the program and by reinstalling msns i was able to "reformat" the chip and that cleaned it up... who knows. Blake

Im still pretty new to megasquirt, but i had it up and running pretty well for the past three weeks using mobys base settings posted in the sticky. i just got done putting in a t3/t4 and 450cc injectors got it running again and was in the process of tuning that when i thouhgt i would try using some other peoples msq's who had 450cc injectors. I had my old settings saved so if they didnt work i would just switch back to my previous settings right? nope! i downloaded moblys msq and tried to start my car and it did start although it was really rough and then died. then i reverted back to my saved msq and it still wouldnt run, every now and then it would kick and sputter but definately was not right. Here is what the car is doing now, i am getting no spark. i checked this by pulling a plug and turning the car over and looking for a spark, and by pulling the center coil wire from the distributer and placing it by the engine where it should spark it it was getting power and again no spark. The thing that is weird is when i turn the ignition off it will spark but just once.... i had my four prong gm hei tested and its good, i am guessing the coil is good but i will test it tonight if i can find my manual to get what the ohm readings are supposed to be, But i really dont think it is the coil which would mean it has to be in the megasquirt itself or maybe the wiring. one last thing, the spark angle always reads 0, before when it ran it would ready 5 when cranking, i think, and 17 at idle ,positive about that. Any thoughts?

i got a kit off ebay, im sure it was the cheaper stuff that is not fiber reinforced, but it still worked out very well for me. I got the 2.5in kit for around 100$ and then just cut the pipes and used the supplied connectors. I think the key is to cut the pipes to that they fit very close, my pipes all but up to each other. If you leave a lot of space between the pipes the connectors can balloon out. My intercooler has 3" inlet and outlet so i boiled my 2.5" connectors and they stretched enough to fit perfectly. Back to your original question, im sure just about any 2.5" connector would; 1 stretch around your 2.75" intercooler and, 2 compress around your 2.25" main pipe. Blake

Might be a bit off topic, but if you do decide to go external, i know you said you didnt...but still, if you changed your mind vinny z had a really good idea that it is pretty simple to copy if you can weld. The idea is you buy two t3 flanges and a piece of three inch wide 3/8 inch steele from any hardware store. Then you bend the steel into a box that copys the shape of the exhaust port from your flanges, basically you make a three inch spacer, cut a hole in the bottom for your external wastegate pipe, weld in your pipe and then bolt it all together. I wasnt really confident in welding to the cast iron so this solves that problem for me. I made one in a couple hours but i havnt tried it out yet because i broke off a stud in the manifold and now its in the machine shop, argh. Search around here and you can find vinny's spacer he made, i think me machined his out of a solid piece of metal. His is pretty impressive, but the one i built should work just as well, just not as pretty.

Whats so bad about the p90a, assuming the lifters still function properly and are not knocking. Reason im asking is because i have a p90a on my zxt and it seems to be working great, no loud lifters, revs smooth, etc. I have been running megasquirt with a stock turbo injectors and volvo intercooler for a few months now and am very happy with it. But of course that got old and now i am in the process of putting dsm 450cc injectors, better IC, and a t3/t4 and looking to make 350rwhp. Should a p90 mechanical head be next on my list?