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ho converion help

if anyone could give me a list of what i need to do this i found a mark VII in the junk yard untouched so what all i need to get out of it to do it and if there are any extra's that would be a huge help ...sorry i don't know everything about this i work on i-6's all day and haven't had as much time to learn the 302 but give me a couple of months and i'll be there so any help on this subject would be great thanks

ho converion help

Reply #1 –
Just buy the Mark VII engine and get the computer.You're good to go.If your car is a 5.0 car already,that is.If you can get the engine cheap enough,just drop it in if it's running,swap the computer and exhaust,and call it a day.It really is that easy.Otherwise,you'll need the upper intake,cam,heads,throttlebody and spacer,computer,fuel injectors and some time and gaskets.It would be a lot quicker to just swap the engine,though.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

ho converion help

Reply #3 –
thanks guys that was a huge help i'm not sure if it runs or not if it does i'll find out the miles cause if there lower then mine y not just get the lower milage block but if not sunday will be a fun day in the junk yard

ho converion help

Reply #4 –
If can't get it to run for any reason, crank the motor by hand by sticking a socket on the crank pully and turning it. Nothing should hang up and everything should move fairly effortlessly.
This will at least tell you if the motor is siezed or if there are any 'major' internal problems.

ho converion help

Reply #5 –
I've done a partial conversion on mine... I didn't know back then that there was a difference in the H.O. TB, EGR spacer, upper intake, etc.  I just shoved a H.O. cam into my '88s block, stuck on a couple heads from an '89 F-150, and went with that.  The catylitics were clogged from previous issues with the car running with a collapsed MAP sensor hose (it ran VERY rich, belching black exhaust all the time) from when my mom had it.  I chopped the exhaust off, not having the money to get the cats replaced ( I was 17, and unemployed) and noticed a bit of an increase in acceleration at higher RPMs, which was what my dad, who gave me the cam, told me to expect.  It came out of his '93 Mustang LX.  THat was after replacing all the vac. lines, etc.
Now I've decided to get the thing running again after a few years, and went and bought a used upper intake, EGR, TB assy off Ebay from what the item description says was a '94-'95 H.O. Mustang motor.  It's got the elbow between the TB and intake, and don't even know if it'll fit, but for the money... Anyway, I was wondering if this thing is the same size as the H.O. TB and intake.  I'd assume so, but have a strange feeling I've learned to trust.  Oh yeah, is the computer swap that vital?
 I didn't mean to hijack the thread, but it's on the same topic, and I figured starting another thread would be redundant.

ho converion help

Reply #6 –
Welcome, this will help you out greatly.
http://www.coolcats.net/tech/advanced/ho_conversion.html

You'll have running problems primarily due to the cam swap.
Here's what you need to get straightened out.
1- '87-'88 Mustang or '86-'92 Mark VII computer - yes this is a necessity.
2- 19lb per hour injectors
3- rearrange plug wires to for the HO firing order

That intake may or may not work. I'm not sure. The bore should be like all other HO intakes at 60mm though.

ho converion help

Reply #7 –
Thanks for the welcome!  I'm glad to see some people not completely absorbed in Mustangs!

As odd as this may seem, the car ran fine with the stock computer, and seems to have been equipped with the 19lbs injectors...  Odd, but that's what it had in it.  I found 14 of the orange/grey injectors, some my dad gave me, and some I pulled when I started the last head swap.  I discovered the firing order changed a while back... it took a good portion of head-scratching, and a couple calls to my dad, who gave me the cam.  The computer was something i wanted to put off replacing as long as possible, being the most expensive part so far.
I'll get the intake in about 4 days or so, and am waiting on a set of heads to come back from the machine shop anyway, it should all be here just in time for the weekend.

ho converion help

Reply #8 –
Cool, double check the part number on the computer. If the car already had 19lb injectors on it and the HO firing order, it might have the right computer in it. It is kind of odd. I wouldn't think the car would run well or even at all if it has the stock S.O. computer.

If not, they really aren't that expensive. I'm sure a couple guys around here have some they'd sell. Make a 'wanted' post in the wanted section and someone might be able to get you one.

Other than that, a junk yard would work fine. Just shop around if you can because one place might sell it for $70 while the next sells it for $20.

ho converion help

Reply #9 –
Maybe I should have been a bit more specific... As far as I know, before I started working on this car about 8 years ago, it was stock, with the exception of the 19lbs injectors... Maybe a former owner had to replace a bad injector or 3 and the shop just installed a set of whatever they had, or could get cheap.  4 years ago I slapped a H.O. cam in and different heads, and it ran fine for a couple years.  I ran the numbers from the sticker on the computer yesterday, and it's a plain stock one.  The only difference I could tell when I put the new cam in, that could have been caused by the computer was that it didn't ramp up to a 1000rpm idle on startup.  It always did that, and would drop once the engine warmed up a bit... it stopped doing that when I put the other cam in but I think it was a sensor problem more than a quirk that came up with the cam swap. 
What's funny is looking back, I could have gotten the entire manifold and injector setup off a mark VII for $50 6 years ago.  It was sittting in the junkyard that I bought my '65 Fairlane from.  The guy said the computer would be an extra $100 (I suspected computer problems with mine back then, I was wrong tho) which is normal around here.  Any kind of ECC is like gold in this area, not sure why.  Finding a car more than 3 years old in a junkyard here is rare too.  The guy that owns the yard also owns a towing service, and I used to drive for one of their competitors.  Up until a year or so ago he would call me up and let me know they had a T-bird in the yard, and that if I wanted anything off it to get up there and get it, because in 2 days it would be crushed.  Sad, eh?
Oh yeah, almost forgot... When I put in the cam I added a set of Crane Cams 1.7 rockers arms, and added a set of hich-rise valve covers, to prevent any clearance problems.

ho converion help

Reply #10 –
Quote from: 5.0willgo;135470
It is kind of odd. I wouldn't think the car would run well or even at all if it has the stock S.O. computer.
 

Most cars built in the same era of our Cougars would from the factory have the injector firing and intake stroke just as much out of sync as a HO cam with an SO EEC. Batch fire systems (all 80's GM's) had two injector drivers, not eight as our v8 EEC Fords do. Half the injectors fired at once. So you can imagine that couldn't be optimized for 4 cylinders on one side of the motor.
One 88

ho converion help

Reply #11 –
Quote from: Rwm8082;135469
The computer was something i wanted to put off replacing as long as possible, being the most expensive part so far.

I bought an '86 5.0HO SD 'Stang EEC from a guy on EBAY for less than 30 bucks shipped..'86-'88 EEC will work, at which point the switch to Mass-Air was made.  They're cheap if you just look a little, guys on the stang forums sell em perty cheap too.
Don't forget the headers and dual exhausts!
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

ho converion help

Reply #12 –
There are a couple ECCs on Ebay I'm watching.  Ebay is a life-saver.  My dad offered me his ECC from his '93 mustang, but as you said, mass airflow...  I've got a set of Hooker shorty headers I bought used a few years back, been running it with 18" flex pipe coming right off the manifolds, and aside from running the risk of ruining a valve, the O2 sensors read a lean mixture.  That's what the Snap-On computer read when I checked the codes last... 3 years ago.  GOt an H-pipe from my dad... another hand-me-down from his mustang.  Wondering how well it'll fit.  Got a good friend that owns an exhaust shop, so that'll help.
Before I start a new thread to ask this... how hard is it to replace the oil pump and/or pickup tube with the pan in?  I know the pickup screen is clogged, my mother drove the car for 3 or 4 years before i had it and had the oil changed TWICE.  THere was sludge all over the engine when I tore into it the first time, and last time I ran it, it held about 10lbs on cold startup, and dropped to 3lbs at hot idle, going up to 5lbs while driving.  Before I write off the main bearings, I want to try replacing the pickup tube and maybe put in another oil pump to see if it goes up any.

ho converion help

Reply #13 –
Well doin it on the ground sucks,if you got a lift it still sucks.double sump!.It can be done ,pull the rad.jack that moter up till you can't jack it no more then some.You could stop before pullin the pan,and switch everything.But it's not the best way,because of the cleaning of the gasket.That oil pan does not come out easy.but it does.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

ho converion help

Reply #14 –
Wow... I was under the impression that the oil pan couldn't be removed without pulling the motor.  It needs a new oil pan anyway, so if it comes out, great!  The stabilizer bar is bent a bit, and pushed against the front drain plug and sump (the result of an unintentional jump) and the rear sump is dented badly, might as well replace the pan too. 
I'm getting a sinking feeling that the main bearings are going to go, and it'll all be in vain.  But, if that's the case and it slings a rod after I get it all done, I've got another 302 non-roller block, with a Lunati cam, an extra 429 and a 390 bored .30 over sitting in the carport doing a whole lot of nothing.  Reading on here what the horsepower gains are after the H.O. conversion, I kinda want to know how the car will act with the H.O. motor.  I guess I'll take the old EFI setup, get a few more injectors, a wiring harness, and put the old EFI system in my Fairlane.  Or, if the bottom end of the 'bird's motor goes, I could just do it all again, on the Fairlane.