knock control

[onephatz]

I'm in the planning process for a turbo setup going into my '75 280z

 

Just some info to start:

f-54 block bored +1mm

je pistons - 8.3:1

stock rods

p90a head

n42 intake (non egr)

mits. 17g or garrett t3/t4 a/r.62 commpressor

front mount i/c

turbo/2+2 flywheel

t-5 tranny

300zxt 3.7 lsd

280zx half shafts

17" wheels

bridgestone potenza's

ect.....

 

my goal is 400 flywheel hp.

 

what I need to know is, is it possable to use any of the stock z fuel or ignition parts and still be able to control knock by controling the things that cause knock(timing,fuel,ect)

OR

do I just need to invest in a stand alone fuel system with spark/knock control(sds EM4 6F)

 

this car is not intended for a daily driver and when it is going to be driven will be driven hard.

I just don't want to have to tear down the motor in 2 months because I bent a rod or broke a piston.

[Scottie-GNZ]

IMHO, with your mods and intended use, the stock engine management system IS NOT AN OPTION.

 

Do the research on aftermarket systems and get the opinion of folks who are using them, not the speculators.

[Guest De Schmaydee]

....yeah ...it aint gonna work..... 'sposed to be able to do it w/the JWT thing..... but 400hp is really a lot.....(i think i'm the only one on here who doesnt have it....)...its the cheapest (ahem.....least expensive ...) route....you have to swap a lot less stuff.....but its still $1800 if you get the injs (420cc), cobra maf,ecu and pay a core for the z31 ecu.....

....the stock afm,vcm and knock sensor are elininated (from my understanding)......

....thats to do it on my stock 82zxt.....your motor has been modded......so it prbly wont use the "canned" version of software....and they'll have to crunch some numbers when they flash the chip........of course i bought all the stuff from them and had them supply my core.....you can get the same stuff elsewhere cheaper (but i didnt want to hear any bs about anything i bought from someone else if it doesnt work right)

.....400hp is a lot more than the tranny and clutch are gonna take on a hard launch.....

.....i kinda looked at other "programmable" controllers....i'd imagine they are better if you know what youre doing......but jeez.....by the time you buy "all" the "stuff" it takes to make it work it looked like mucho $$$......

............s

[jgkurz]

Hi onephatz, Your setup is similar to mine and I would not consider using any variation of the stock 280ZXT EFI. Yes there are ways to add more fuel, but you will have serious fuel distribution problems. At the high boost necessary for 400HP you better not go lean, even with JE pistons. The least expensive method in my opinion is to buy a used Tec2, Haltech or SDS if it's available. I've also heard good things about the Wolf3D system. The JWT system works well, but programmable is the way to go in my opinion.

 

The knock sensor is a whole different issue. I am testing a VG30ET style knock sensor with my Tec3. It is a one wire sensor as opposed to the stock two wire. It also screws into the the L28ET block without any modifications. If I get it to work correctly I will only enable it under about 4000rpm's. In the higher rpm's, the sensor will pickup erroneous noise causing retarded ignition when no detonation has occured. If my memory is correct, I think the JWT system doesn't even use a knock sensor.

 

By the way, you might consider a T04E hybrid turbo rather than the Mitsu setup. It would be MUCH easier for you.