jeephack

88 cherokee non high output 4.0, obd1. I'm making a custom manifold, then grabbing a turbo off a eclipse, talon, or laser. Injectors are on it are 19#, has a knock sensor, compression 8:1, only one o2 sensor on the exhaust pre-cat on the current header, with a gutted cat and glasspack (trail vehicle) has an external FPR, looking to do a turbo set-up for cheap, for fun. My friend has a few turbo vehicles and when i brought it up to him he was in for helping but started talking about piggyback programmers and air fuel ratio guages, 24# injectors, things that would kill the budget. I would rather spend the money throwing some rings and bearings on it. I remember a guy a while ago had a similar setup with no comp. Mods. said he was running 8 psi. Just to keep the top end from blowing i would want 6 psi. Fab is no issue, at all.ive got benders, welders, about 6 years of metal working experience. Issue is computer stuff, since its obd1 and really has no sensors how would i keep it from running rich? Is an old renix smart enough to know the difference if i keep the psi down? Do i need those huge injectors and better fuel pump? Need a summer project since we had another baby and cant venture to my wheeling haunts till he gets a bit older. Advice is welcome and appreciated, if i can do it ill make sure to post up the build for reference.

busa4

my advise to you is shitcan the stock computer and purchase a megasquirt 2. this stand alone computer will do it all. it has a 2.5 bar map sensor built into it so its easily tuneable for boost.
you will need a larger injectors based on hp needs, a tps(throttle position sensor), and a wideband a/f ratio gauge in order for this setup to work. wiring the system is easy. since your using an older obd1 system the computer may not be able to process fast enough for boost and the stock computer needs to be chipped.

if there is a performance company that can chip your stock ecu with a custome tune for your setup this will be the cheapest way to go. im not familiar with jeep vehicles so hopefully someone may be able to steer you in the right direction.

personally i would use the megasquirt 2. you can get it unassembled for ~200.00 and build it yourself or assembled for ~400.00. it uses a laptop to program the tune.

laith

get your self a mechanical fuel management unit. they are fairly cheap, and will raise fuel pressure in the fuel rail according to boost. thats pretty much your only alternative to electronics/tuning.

buy a bigger fuel pump, the fmu, retard timing a couple degrees, make sure you have a newer tune up, put a check valve inline with the map sensor so it doesn't go ape ---- when it see's boost. and run an oil catch can.

at 6psi, it's not necessary to go all out with a standalone ecu.

roman

did you finish the project?