Just thought I'd share a few pics now that I started the MPFI swap on my hot rod/beater 90 Cavalier.
The rundown:
Car is a 1990 5 speed Cavalier with no options. It has the manual steering rack.
For now I've decided to reuse the 1990 short block. I have a 95 roller cam 2.2 for the car, but I'll swap that in when I burn up the clutch.
I wanted to get all the bugs out before I swapped the short block anyways.
1994 home ported head.
1992 ported MPFI intake.
1990 ported exhaust manifold.
I got pretty much everything done yesterday until I ran out of parts. The only thing left is to figure out and plumb the fuel lines by the gas tank, and put the thermostat housing back on that I drilled and tapped for more sensors. I have a stock MPFI air intake setup I'll probably throw on for now, but I have the ID cold air from my old 2001 Z24 I'll make fit eventually.
Heres some pics.
Lemme know what ya think, and feel free to throw in any suggestions.
JLP
Don't forget to connect the hose clamp on the upper rad hose.
Can the fuel lines be connected to the originals near the fuel compartment?
Also, watch the pump. Some TBI pumps simply can't generate the pressure required for mpfi systems.
Have fun!
-->Slow
Got it running!
It was that dang loose hose clamp.. thanks for the heads up!
Couple quick questions though..
Whats the 4th wire for on the 1990 fuel pump wiring harness? My 1993 pump harness only had 3 wires.
Also, on the MPFI motors.. which sensor is the one that attaches to the vacuum lines for the EGR etc.? Wondering about these cause I'm trying to track down a nasty idle that sounds like the motor is dead on a cylinder.
On the road at WOT I can guarantee its not dead on a cylinder though!
This thing hauls!
JLP
GM often uses 2 grounds on the fuel sender. One will ground the metal sender assembly, the other runs directly to the fuel pump. If the sender you're using has only 3 wires then you can choose either one of the ground wires in the harness to connect to.
There's an EGR solenoid which blocks vacuum to the EGR valve. The simplest way to check for an EGR related issue is to remove the hose at the valve and plug it temporarily.
Try
this diagram. Also don't rule out the basics, like a faulty ignition coil, a vacuum leak at the intake, or partially plugged injector.
hth
-->Slow
Nicely done....
Jeremy, drop the tank and install a Z24 (V6) pump when you have the time. We did that on our MPFI swap and never had fueling issues, even with a 75HP Zex dry shot. Dropping the tank can be PITA, but it's worth the effort.
I'd block the EGR all together, and keep the recirc exhaust from gooing up the inside of the intake manifold. Check for vacuum leaks, old cracked vacuum lines,as well.
Thanks for the thoughts guys!
I changed about a billion parts to no avail tonight. The car still idles horrible and loads up.
About the last thing I can come up with is a faulty injector or two, but FWIW they all ohmed out ok... ? Can injectors still be bad even if they ohm out OK?
As far as the gas tank, I carried on the "tight a$$" theme and shoehorned in the gas tank from a parts 93 Cav I have. Not exactly a direct fit, but its in there now!
JLP
An injector can be mechanically bad even though it is electrically good. If it were sticking completely cloesed, for example, your ohm test would show no problem.
I usually try to figure out which cylinder is the problem child. If you can reach the fuel injector connectors you can try disconnecting the injectors one at a time to listen for rpm drip and increased engine roughness. The injector that doesn't make a difference is on the bad cylinder. When you find the bad cylinder, you can try swapping the injector to another cylinder and then check to see if the problem moved with the injector.
Don't forget vacuum leaks at the bad cylinder. These can be found (sometimes) by spraying flammable carb cleaner at the base of the intake near the head and listening for engine rpm to increase.
Cheaper is better!
-->Slow
Well, I changed the injectors tonight and the car responded with a much cleaner idle. I got air intake all figured out and mounted, and worked a little on cleaning up the swap.
It still has a little twitch at idle, and also cuts out if I hit the gas too hard from an idle. Now its acting like a trademark vacuum leak, but I ran out of time tonight to fiddle with it any more. At least the car is drivable now, so I plan to do a basic tuneup before I go much further.. (oil change, fuel filter change, put new plugs in it etc.) then put some miles on it and see how it does.
I'll get some more progress pics by the weekend for anyone interested.
JLP
Yep, interested. I love this type of project.
-->Slow
Not much new to report really...
I'm daily driving the car, and it still isnt running perfect. I couldnt find any vacuum leaks, and the idle is still a little wavy and I can get a little black smoke when I rev it up. I'll keep plugging away at it.... its gotta come around.
JLP
althought the air is cooler over there, if you don't plan on running a/c i recomend striping all your a/c componets and sticking the filter over in the passenger side fender weel. tons of cooler air rushes in there. and u can cut out a lil' of the plastics and get more colder air. plus it runs over LESS hot spots than yours.
but way to go on the swap. i wanted to do that with my 2g but could never find the time to drop it off at the shop
...
Great work SeriousZ. I am curious as to how you went about porting your head, intake and exhaust. What sort of tools did you use and how long did it take? How much material did you take off and did it make a noticable difference in performance? I'm considering doing something like this to my 2.0L MPFI motor. I'm looking for high rpm gains for a very low price.
Thanks for that info. It's really good to know. Did you ever bench flow the head before and after you did your porting? Did you notice a difference in power and if so, was it more in the low end rpm range or in the high end rpm range?
I really didn't touched the head except for a minor gasket matching blend and ridding the port entries of casting flash.
I spent all the time on the intake, because it was so bad. The runners were supposed to round to match the gasket/ cylinder head port, but looked like a cats eye ( ). Over an 1/8" mismatch in some areas.
My apologies but, before and after flow numbers were not taken, and i'd be the first to say bigger is not always better when porting. On the other hand the manifold was not even in the right zip code compared to the cylinder head, shape and cross section wise.
I never trust butt dynos, but the car picked up a few tenths on a 1/3 mile oval.
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Project S-Bird
Yes Michael, this is the same Jeremy. Very nice work on the intake manifold you did, I cant take credit for that!
As for the head, I went at it with the above mentioned S-A kit and a pnuematic die grinder. Being that this was my first cylinder head I've ported, those basic tools worked well for me. I didnt alter any shapes in the head, but rather worked on cleaning up A LOT in the bowls and gasket matching. I also polished the complete exhaust port and all the chambers. Going on the cheap factor also.... I reused the stock 7mm valves and had my builder put a backcut on them. The tight budget didnt allow for flowing the head either.
Whether it be a factor of the car not running perfect yet or just how the setup is acting... the motor is a lot stronger on the bottom through mid-range. The cold air totally changes tone at about 5200 RPMs, and thats all she wrote as far as top end power.
Once I get everything dialed in perfect, or whenever I nuke the stock clutch(whichever comes first)
thats when I'll swap in the roller cam 95 2.2 I have for it. Hopefully that will perk it up a little too.
Thanks for the interest guys!
JLP
good work, i did all this myself on my 94 which is mpfi but i ported everything and added some 1.6 roller rockers and i felt a difference. Definitly block off the egr so you don't dirty up the intake manifold. I got some extra roller rockers and egr block off and other things if interested.
cavaliers been laid to rest
The saturn is being born
a new cavalier is in the mist
hmm perhaps i should do this to my 90 4dr..any better gas mileage with it?
FDP 62MM TB, FFP Performance Chip, FFP Underdrive Pully, WAI, Hi Flow Cat, 2.5" Catback, Functional Ram Air Hood, Centerforce Dual Friction Clutch
