PreludeOnline.co.uk
Honda Enthusiast web site .
Welcome to PreludeOnline.co.uk
Modifying, Tuning, Information
Welcome to my site
for the Honda Prelude VTEC
Tuning
Rather than tuning the original H22A2 engine fitted to UKDM versions of the Prelude, I decided to source a used H22A7 engine from the 212ps Honda Accord Type-R.
This has now been professionally installed by Richy at Performance Autoworks for over 2 years.
This is not a direct swap, but Performance Autoworks have done this conversion several times so are familiar with what needs to be done to make this a smooth conversion.
To keep the swap as simple as possible you will need to keep the Prelude intake manifold and distributor, and use the Prelude engine loom and NOT the Accords OBD2B one.
The reasons for using the Prelude parts is because the wiring on the H22A7 engine loom is different, and the crank trigger is near the oil pump not in the distributor. You will need to remove the crank trigger sensors from the engine.
Also, although the H22A exhaust manifold from the Accord is a much better item than the Prelude one, it can't be fitted directly to the Prelude without some fettling of the front crossmember and engine mount. So again, the Prelude exhaust manifold will need to be re-used.
Once the engine is fitted and running you will benefit from the higher compression (11:1) pistons and the higher flowing head and even more aggressive VTEC cams.
If you do this conversion you can continue to run the Prelude P13 ecu with this setup, although a Hondata or Neptune RTP setup would allow you to tune the car on the dyno and unlock the engines full potential.
One last thing which will cause an issue is if you are fitting the U2TQ LSD gearbox from the Accord. The Prelude VSS sensor cannot be used with this gearbox, and the Accords PS gearbox drive and VSS sensor does not use the PS lines for the speed sensitive power steering. So the PS lines have to be looped on the Prelude rack to get around this problem.
This will leave you with a slightly heaver power steering at slow speeds but will obviously feel normal at higher speeds. You may hear the PS pump whine a little at slow speeds or whilst parking, this is just because the pump has to work a little harder and will not cause any long term damage.
Other options are to tune the engine you have, or go for a rebuild using uprated parts.
If you decide to tune with bolt on bits, then look to replace the exhaust manifold with a good one (can be expensive) and the complete exhaust system. You can also experiment with the intake, but you will find eventually that the standard one isn't bad and a replacement drop in element is all you need.
If you do decide to replace, then stick to branded items like AEM V2, Comptech etc. and avoid cheap ebay items. These make the intake roar sound awesome, but you will find they lose torque at the expense of maybe 1-2hp at the top end.
If you decide to have engine work done then I would highly recommend you use a garage with the necessary skills and experience and who will guarantee their work. Ask for at least 3 customer referrals, and contact them to talk about their experiences dealing with the company before you do anything. I have made this mistake before when choosing Inline Motors of Wolverhampton to do an engine rebuild. Do not make that mistake!
To keep the swap as simple as possible you will need to keep the Prelude intake manifold and distributor, and use the Prelude engine loom and NOT the Accords OBD2B one.
The reasons for using the Prelude parts is because the wiring on the H22A7 engine loom is different, and the crank trigger is near the oil pump not in the distributor. You will need to remove the crank trigger sensors from the engine.
Also, although the H22A exhaust manifold from the Accord is a much better item than the Prelude one, it can't be fitted directly to the Prelude without some fettling of the front crossmember and engine mount. So again, the Prelude exhaust manifold will need to be re-used.
Once the engine is fitted and running you will benefit from the higher compression (11:1) pistons and the higher flowing head and even more aggressive VTEC cams.
If you do this conversion you can continue to run the Prelude P13 ecu with this setup, although a Hondata or Neptune RTP setup would allow you to tune the car on the dyno and unlock the engines full potential.
One last thing which will cause an issue is if you are fitting the U2TQ LSD gearbox from the Accord. The Prelude VSS sensor cannot be used with this gearbox, and the Accords PS gearbox drive and VSS sensor does not use the PS lines for the speed sensitive power steering. So the PS lines have to be looped on the Prelude rack to get around this problem.
This will leave you with a slightly heaver power steering at slow speeds but will obviously feel normal at higher speeds. You may hear the PS pump whine a little at slow speeds or whilst parking, this is just because the pump has to work a little harder and will not cause any long term damage.
Other options are to tune the engine you have, or go for a rebuild using uprated parts.
If you decide to tune with bolt on bits, then look to replace the exhaust manifold with a good one (can be expensive) and the complete exhaust system. You can also experiment with the intake, but you will find eventually that the standard one isn't bad and a replacement drop in element is all you need.
If you do decide to replace, then stick to branded items like AEM V2, Comptech etc. and avoid cheap ebay items. These make the intake roar sound awesome, but you will find they lose torque at the expense of maybe 1-2hp at the top end.
If you decide to have engine work done then I would highly recommend you use a garage with the necessary skills and experience and who will guarantee their work. Ask for at least 3 customer referrals, and contact them to talk about their experiences dealing with the company before you do anything. I have made this mistake before when choosing Inline Motors of Wolverhampton to do an engine rebuild. Do not make that mistake!