cooling system upgrade

[dohcfiend]

i recently put a 50 shot on my z34 and when i use it my engine generates more heat than the cooling system can compensate for. the temp guage goes to halfway after 15 sec. of using it. any idea's on the direction i should take on upgrading my cooling system and are there aftermarket hi flow water pumps for this motor?

FYI: the jets i was told to use were 37 n2o and 22 fuel. and i have sprayed it 2 times. probably won't use again until i can increase the efficiency of my cooling system.

[SappySE107]

Are you sure its not running lean? I really don't see how a 50 shot is going to increase the temps that much without running on the lean side. I could be wrong though, since I don't know how well the fiero cooling system is compared to the W body. Maybe you need a better radiator, or you have a lot of rust/scaling buildup in the block.

[dohcfiend]

don't know either but my car is a w-body; i have a 94 z-34. after i am satisfied with the engine output and it will go in a fiero, but no time soon.

i will check it out though i will hook my scanner up and have a friend monitor the 02 sensor readings while i do a 10 sec squeeze.

also my car will heat up during stop and go traffic. other than that during normal operation my engine runs quite cool. your input is greatly appreciated, thanx.

[jmgtp]

I don't think the heating up is that unusual. Exactly how hot? Half way on my dash gauge is 220* F. I also have an aftermarket digital readout gauge for water temp. Once the thermostat (I have a 180*) opens it usually sits right at 182* during cruise, idle will creep up to 190* or so at a long traffic light. But at full throttle for 15 seconds or so it gets up to about 200* and on hot summer days it'll get into the 210s on a lengthy WOT run. I think 200s would be normal for full throttle runs, especially with nitrous => but thats just speculation

[dohcfiend]

you are right sappy it does go lean on n20 but that is expected right? it is an oxidizer? would you recommend larger fuel jets or is it just normal for the application? well on the run i did today it was about 7 sec and it was about 38* outside but the guage moved v/little. the last time i did the n20 it was for 15 sec and it was about 65* outside. just for speculation i think the n20 screws up the o2 sensor because it will stay on lean(usually it will change from rich/lean) until i cut the car off and restart it. also would you recommend that i read the plugs? would that determine if any damage has occurred? if not what other test can i do to check things out?thanx every1.ltr.

[LowSC2]

If it's definately running lean you should richen it up a bit. I'm assuming you're using a wet kit right?

[dohcfiend]

If it's definately running lean you should richen it up a bit. I'm assuming you're using a wet kit right?

yep, should i use larger a fuel jet, smaller n20 jet or both?

[dohcfiend]

i pulled and read the plugs. i am running lean and i thnk i need colder plugs. i need a n20 guy to tell me what to do on the jets. i have 37 n20 and 22 fuel.thanx.ltr.

[pocket-rocket]

I have read up some on N2O, but I am not an N2O pro. You should always run a little on the rich side though, never lean! If you keep doing it, kiss your pistons and valves goodbye. If you stay with the 37 N2O jet, change to a 25 fuel, or if you keep the 22 fuel, go to a 33 N2O jet. too keep the 1.5:1 ratio of N2O to fuel (which should keep you in a slightly rich state, or safe).

[dohcfiend]

thanx. i don't have a 25 how about a 26? i have also went to a colder sparkplug, flushed the rad, removed the condensor(a/c didn't work anyway), installed a homemade cold air kit, which reduces intake air temp(which in itself doesn't do too much but the ecm will change a/f mixture and or timing based on the colder sensor readings) i am considering installing a 160* stat 1. it will run a little cooler and 2. the ecm will richen the fuel mixture a little. but i will only do this if the changes don't yield the results i need.

i am going to put a few miles on these new plugs to check for fouling if they don't i will burn a little n20 and check them again for a lean condition. and go from there. and i will also monitor everything via aldl scanner.

give me about a few days-week and i will have the results.

[pocket-rocket]

26 should be fine, better rich then sorry, lol.

[dohcfiend]

well, the new plugs aren't fouling and i sprayed the n20 and the sensor readings are good . i have to read the plugs tomorrow but i am confident. now comes the final phase of fine tuning. which consist of backing off of the fuel jet until the lean condition comes back and go 1 step up. what is the signifigance of the 1.5 ratio? cause as of now mine is 1.1!!! should i continue tuning until i can achieve 1.5 n20 to fuel ratio and sacrifice driveability? i gotta giv a shout to pocket-rocket. thanx.

[pocket-rocket]

All of the charts I have seen keep it at a 1.5:1 ratio, which keeps it slightly rich so your engine doesn't go into meltdown mode. Carbon is easier to clean then changing parts I would just run it at the 1.5 ratio instead of messing around with a possible lean condition just to stay on the safe side. All of the horror stories you hear come from people that didn't set up their system right, and blew their engines (read ran them too lean). N2O is very safe power when set up right. It has been used for over 50 years now, and anyone who has had it that long that sets their sytem up right will swear by it that it is not a destructive way to get more power. Also it is not recommended to go more then 33% of your stock engines power if you haven't upgraded the internals to stronger materials, like forged pistons and rods. Everyone I have heard from on the DOHC feels that a 75hp shot is the limits of safe reliable use on stock internals, so I would stay at 50 if I were you. Thanks for the shout out, lol. Glad I could help and that you didn't blow your engine

[dohcfiend]

the 1.1 i was talking about is on the rich side i have a 37n20 and a 26 fuel jet. should i keep trying to tune my engine richer and try to get my fuel jet down to 22 to get a 1.5? or will the setup make the same amount of power with the 26 instead of the 22? in which case i should be happy with what i have. ok, that wasn't very clear here it is again, increasing the fuel jet size(going from 22 to 26), does it decrease the power increase gained from the n20?

i will however try to go to the 22 again because i did 3 things at once, increased the fuel jet, went to colder plugs, and installed a cold air intake. which changed the sensor readings and in effect changed the a/f mixture and the timing.

[dohcfiend]

SUCCESS!!!!!

it is done!! i dropped it back to 22 jet and it still didn't go lean. so i consider that matter finished.thanx to every1 that gave their 2 cents.ltr.