EFI head on carb engine ?

[Whistler225]

will this work? Are the heads the same or not? Someone on here is selling a head, and I need a new one. His came off an LXI, I have an LX.

Any insight would be appreciated......

[Whistler225]

that doesn't help me lol.....are you saying it will work, or not? I looked at Majestic Honda's website last night and the cylinder head part numbers are different, but the head gasket and every single other part on those heads are the same part numbers between the two....

[MessyHonda]

yes it will work. all you got to do is change your valve cover. they are the same engine expt that the Fuel injected has a higher compression...and the cam is more agressive....i got a fuel injected cam for my carbed since to change the whole head would be a bitch....il see when i can install it so i can tell you how it worked.

[Whistler225]

thanks. Is the FI engine higher compression because the head is shorter, or because the pistons are taller? If the head is shorter I can see that causing problems if your timing belt snaps.....which won't be an issue for me since the timing belt will be getting changed at the same time as the head.

So the FI head has the same mounts for intake as the carbed head? I know this might sound stupid but I just want to make sure. I would like to be able to just take the head up to the shop where the work is going to be done, hand it to the guy and say "ok I want this on my car, and please change the timing belt at the same time," and not have the bill skyrocket because the guy had to do something wierd to get the intake manifold on it....

[Jasonf860]

Ok, I know they are probably exactly the same head except for the cam, but I just want to be sure before I go swapping them. A budy of mine has a fully rebuilt head from his 89 LXi sitting in his garage since he junked the car a year ago. (It's a bone stock rebuild btw) Since my lx started leaking oil from the head gasketand I plan on changing the gasket, I thought it might be a good idea to swap in this nice rebuilt head since I can get it free. Not to beat a dead horse if it's already been asked, but I want to be sure it will bolt up and work, and what , if any gains I might see from the cam.

[MessyHonda]

yeah you can use the same head....the only thing is that you might have problems with the dizzy...you might want to get the EFI one since you can mod it to work with the carb.

[Jasonf860]

Good question, i just posed it a few ago without a proper search...... My bad. So Whistlers question about compression... Is it the head is shorter or the pistons taller?

[A20A1]

I think they said the valve stem length is different in the carbs.

I would keep the Carb head and run an EFI A20A3 block and get a stage II colt Triflow Regrind

[Whistler225]

I haven't really posted much since getting my work done:

The FI head works fine, though I should have had the valves done before it was installed. They make a bit of rattling noise which is kind of annoying. The original valve cover fits it fine as well, though I suspect the mechanic didn't install the gasket properly because it's leaking.

I also had the carb rebuilt, a new intake gasket installed, along with a new timing belt, water pump, and serpentine. I had the AC compressor removed.

My only real complaint is that now the car seems to have lost a little of its juice. I don't know if the leaking intake manifold gasket was allowing more air into the intake and giving me better HP, or if it was something else. I did find that the mechanic disconnected the vacuum line from my secondary (the car was completely gutless when I got it back). Putting the line back on helped a little, but not completely. I also learned that I have a minor lower engine knock, which is depressing after putting about 1300 dollars into the top end of the engine.

[Jasonf860]

So basically your saying your getting LESS HP with the efi head? Seems you should be making more with the difference in lift and duration being higher/longer on the efi cam....

[Jasonf860]

Ok, based on what Whistler said, has anyone just used the EFI cam in the carbed head? Also, my question is this- since I'm not rebuilding the head right away, will putting the cam with higher lift etc in damage my vales as they have 210k on them with the lower lift and duration cam?

[smufguy]

Ok, based on what Whistler said, has anyone just used the EFI cam in the carbed head? Also, my question is this- since I'm not rebuilding the head right away, will putting the cam with higher lift etc in damage my vales as they have 210k on them with the lower lift and duration cam?

Alex put just the efi cam on his A1 head and he said he felt the difference. No your valves will not hit the pistons when they are @ TDC nor will ur valve stems get damaged, u will be fine. The lift is minimal, around 0.4mm higher lift if any.

[Jasonf860]

Awesome Exactly what I wanted to hear!

[Whistler225]

So basically your saying your getting LESS HP with the efi head? Seems you should be making more with the difference in lift and duration being higher/longer on the efi cam....

I don't know if I'm actually getting less hp or not. All I know is that the car struggles more on hills now than it did before I had the work done. The trade-off to all the work was that the car idles perfectly now, though it still vibrates at stop lights because I haven't done the motor mounts yet.

I suspect my hp issues may have more to do with an ignition issue than fuel delivery. My hot lead is corroding badly around the battery terminal, and sometimes the car won't even start unless I bang on the terminal clamp to move it a little and get better contact. I've tried cleaning it up but it just comes right back. I think I have a short somewhere (hell, I know I do....there's a fuse in the box under the hood that drains the battery if I leave it plugged in. It doesn't seem to do anything else, so I leave it unplugged), and I think it might be draining current from the ignition circuit.

I also discovered that the guy who put my head on disconnected the vaccuum line from my secondary and plugged it. I took the plug out and reconnected it (not entirely positive I connected it to the right place though), and it helped a little, but the car still doesn't get much boost when I kick it down a gear.

I'm going to have to wait to try and work out my hp issues, as I'm redoing the front brakes this weekend. Maybe over the next few weeks I'll get into it a bit more.....I'll let you guys know what I find.

To address the higher/longer lift on the efi head: if the valve lift is longer, wouldn't that mean the head is actually a little taller than the carb version? If that's the case, I would be getting less compression from my pistons, since they are the originals and are leaving more space in the cylinder, wouldn't I?

[smufguy]

To address the higher/longer lift on the efi head: if the valve lift is longer, wouldn't that mean the head is actually a little taller than the carb version? If that's the case, I would be getting less compression from my pistons, since they are the originals and are leaving more space in the cylinder, wouldn't I?

The lift is the specs on the camshaft, not the head. the head height is the same for the carb and efi. As i have mentioned before many a times, the valve length on the carb head is a tad bit longer than the efi. and thats the only difference between the both heads.

[FyreDaug]

Your power "loss" could be due to the fact that the head was replaced and the ditributor (ignition timing) isnt set the way it was before. I know if I advance mine I get more juice from it. Check that out, if you can compare the location of the dizzy on both heads you might be able to tell if the old one had more advance


[[[surprised no one else said this yet]]]

[shepherd79]

plus you said that your battery terminals are corroded. well take them out and clean them. you probably not getting enough power to the coil.

[alboy86]

hmm well if ya put the efi head in there will it still pass smog and everything live in cali i was reading about it maybe gunna give it a try since i cant rebuild the head or get a cam grind well i could but i dont want to spend the money doing it then just taking it in to have them fail it plus i was figuring while i was at it i could p&p it

[MessyHonda]

hmm well if ya put the efi head in there will it still pass smog and everything live in cali i was reading about it maybe gunna give it a try since i cant rebuild the head or get a cam grind well i could but i dont want to spend the money doing it then just taking it in to have them fail it plus i was figuring while i was at it i could p&p it

dude just get a lx-i you can do more mods than a carb

[Whistler225]

yeah, I kinda figured part of the problem was the fact that I'm probably not getting enough current to the coil....but I haven't checked the timing yet. I guess I trusted the mechanic to set it properly when he installed the new head. I know the vacuum lines to the distributor are ok, as I've checked them already. I bought a new wire for the hot side of the battery, I just gotta get it put in. I also have to re-tighten the alternator belt. For some reason, it's come loose after being installed.....boy is it a pain to get to! I'd imagine it can't be helping that the alternator isn't turning like it's supposed to.