Hey fellas... I just aquired a 99 prelude H22A4 motor with 27,000 on it to replace my tired and true 93 H22A1.. The new motor comes with EVERYTHING from the axles, ecu, tranny and even the throttle cable from the 99 prelude.. I need to change this motor to OBD1 for performance purposes. What do I have to swap from my old motor with the new one. Distributor, ECU, Injectors... What else??

Thanks guys!

Also, do the 4th gen preludes have different gear ratios from the 5g preludes? Or is the difference just in the bigger wheels?

 

In addition to what you listed already, you need the complete engine wiring harness. I think this is all one piece. But if not you need specifically the ECU harness, fuel injector harness (including resistor pack!), and distributor harness. All are wired differently on the 5th gen so you need the 4th gen ones.

You will also need to keep your 4th gen exhaust manifold and dp because I think the 5th gen has a different length unit...

4th gen VTEC 5spd tranny has tighter gearing than the 5th gen. I used to own a 4th gen VTEC, and now I have a new 5th gen... Trust me, you want to keep the 4th gen tranny gearing...

Andrew

 

First of all, CONGRATS COREY! That's great. I'll miss your smoke and pops and bangs though.
Sounds like between you and aklucarits you've got it all down. I've heard some folks are able to do it without getting an entire distributor. I don't know how though. I've also heard the ratios are higher on 5th gens.
Here are the ratios from my 5th gen Helms:
1st 3.285
2nd 1.956
3rd 1.344
4th 1.304
5th 0.812

R 3.000

Final drive 4.266

I dunno what the 4th gen ratios are. By the way I'm quite sure the 5th gen axels are longer so you'll need 4th gen axels.

HTH

Edit: me you've already got your 4th gen axels!


[Modified by 4doorH22, 10:26 PM 9/22/2001]

 

Thanks fellas for the help!!

Here are the gear ratios for the 4g VTEC Vs 5g

1st 3.307 vs 3.285
2nd 1.950 vs 1.956
3rd 1.360 vs 1.344
4th 1.071 vs 1.034
5th .870 vs .812

Final drive is the same

Looks like im gonna stay with my 4g tranny, lower gears across the board, I would like to have the higher first gear though... If 5th wasn't so hi in the 5g lude I would use the 5g tranny.. I really need a good 5th though because I get into 5th at most tracks..

I can't use the 5g axles? Well ****! I wanted to use them

 

Well do try to use your 5th gen axels.
Man I'm looking at these ratios and I'm getting dizzy.
I forget. Say for first gear, for every turn of the input shaft, does the output shaft turns 3.307 times, or vice versa?

 

Something like that, i know is the higher the #, the lower the gear, as in you would have to have more RPMs to roll at the same speed..

 

Looks like the 5g has a lower 2nd but the 4g is lower in every other gear.
Lower ratios mean you can't go as fast in each gear, right?
But you do get better acceleration at the expense of longer legs and you're revs don't drop as much so you can stay in the powerband more.

 

Well Cory, I just got my ODB II converted to ODB I. I too am using the 4th Gen VTEC Tranny instead of the 5th Gen. When you switch over the wiring harness there are a couple of wires that need to be made a little longer. One is the O2 sensor, if I am not mistaken. The ODB I wiring harness is a little short to connect to the H22A4. Then there was one more wire and I can't remember what it goes to, it is late, I will look tomorrow and tell you. I think you might be able to re-route that wire though. Congrats on the motor! Let me know when you get it going.

 

Oh hey also unless you want to make your fuel line longer you'll need to use your 4g fuel rail (the 5g rail exits on the opposite side).

 

Well...there goes Corey's trade mark as the three color smoking prelude. I will miss it as well. E-mail me with the funeral date. I think that engine kind of grew on us all a little bit.

 

We are gonna revive that motor, might have to go in Morgan's Accord...