Engine Swap

[BluAccord]

Hey guys, I have a question. Is there a difference between a 91 lx and a 93 ex. i just did a swap the lx for the ex. But on the supposed ex block its stamped with f22a1. The place i brought the engine from said they are the same.

[dj_ender]

A 93 EX should have a F22A6, which has more HP than the A1.

[wagon-r]

Technically, the engine blocks for the F22A6 and the F22A1 are the same. But the F22A6 came with a better camshaft with matching valve springs, a 2-stage intake manifold, a better exhaust header, a windage tray, and a different ECU, which were good for an additional 15 hp.

[ahdiofreak]

Did the 91 ex's have a6's? But yeah if your lx motor said a1 and your ex motor says a1, you pretty much got the same motor.

[H311RA151N]

Did the 91 ex's have a6's? But yeah if your lx motor said a1 and your ex motor says a1, you pretty much got the same motor.

USDM 1990 & 1991

DX, LX: F22A1

EX: F22A4


USDM 1991 SE: F22A6


USDM 1992 & 1993

DX, LX: F22A1

EX, SE: F22A6


In a sense, the F22A6 replaced the F22A4 in the EX in 1992.



F22A4 is ran off a PT3 ECU just like the F22A1 where as the F22A6 is ran off a PT6 ECU. The only difference in the F22A1 and F22A4 is the F22A4 has a tubular 4-2-1 manifold as where the F22A1 has a 4-1 cast manifold.

The F22A6 has a cast 4-2-1 manifold but its not tubular like the F22A4. Therefore it is widely believed by most that the F22A4 has a better factory manifold than the F22A6.

The F22A6 also has a 4B stamped camshaft as where the F22A1 & F22A4 have a 3A stamped camshaft. The F22A6 has a slightly more aggressive camshaft profile. The F22A6 also has a wideage tray and more performance oriented valve springs to compensate for the more aggressive camshaft as well as IAB's in the intake manifold.

F22A6 also has an oil cooler.

[dj_ender]

I swear the 91 SEs had an A6, could be wrong though.

[H311RA151N]

I swear the 91 SEs had an A6, could be wrong though.

I forgot the oil cooler on the F22A6. And you are correct, the F22A6 was in the SE in 1991. Nice catch!

[BreckAConner]

I swear the 91 SEs had an A6, could be wrong though.

My 91 cb9 ex has a a6. Which I thought was weird for the 90-91 cb7s not having them. You could be right about the SE I've never checked to see if they had them at the yard.

[deevergote]

Any 90-91 EX that has an F22A6 has been swapped. 90-91 EX models came with the F22A4 in the US.

BluAccord, I don't know what "DA AUG" means, but if you're from Canada, then an EX model is the equivalent to an LX model in the US. That meas it would have an F22A1 from 1990-1993.

As said, all F22A 1/4/6 blocks are essentially the same. All 3 engines have different exhaust manifolds. Other than the exhaust manifold, the F22A1 and F22A4 are identical. The F22A6 will have an windage tray in the oil pan, different valve springs, a different camshaft, a different intake manifold, and a different ECU. An oil cooler will also be found on some F22A6 engines (it may only be on automatic models... I can't recall, and I didn't look it up prior to typing this.)

If your engine is stamped F22A1, then the block at least is of an F22A1. If a windage tray wasn't added, it's not the same as the F22A6 block. If the intake manifold is a single-stage manifold (no IAB system), then that is the F22A1 intake manifold. Chances are good that the camshaft and valve springs are also F22A1.
The good news is that no extra wiring will be needed to install the engine if its an F22A1. You won't gain that extra 15hp like you would with the F22A6, but you won't need to wire the IAB system and swap the ECU, either!

[BluAccord]

engine swap

Ok guys thanks for the info. It turns out the dude at the place where i brought the engine lied about it being an EX. It is a 93 LX, the motor has a 4-1 header which we know came on the DX and LX motors. It idles rough up and down llike crazy, im thinking its a vaccum leak, we are going to put my complete upper plenum fuel rail, and iac system on it i know that there is no leaks in mine. 'any advise would be welcome. thanks

[dj_ender]

I would check for vacuum leaks before doing the intake swap. Also bleed the coolant system.

[BluAccord]

engine swap

oh yeah i forgot to include my timing is way high, when i look for it with my timing light the mark is way off it is about if i were to use inches. about 4 to 6 above the V mark used to set the time. Do you believe this is caused by the vacum leak? I sprayed carb cleaner around the vaccum lines, the plenum and the iac area no difference in idle.

[dj_ender]

Did you use the red line or the white one? You use the red one.

[BluAccord]

Hello, what do you mean red or white line? I don't see a red or white line.

[dj_ender]

Then how are you setting the timing?