I've tried searching for a few days about details about a smallport swap but I couldn't really find a definite answer.
I'll be using my largeport electronics, tvis intake w/t3 adapter, 7 rib largeport bottom end with rwd parts.

I do know that i need to cap off the oil return line on the head, but what about the fuel injectors? Should i go ahead and source a set of smallport injectors(but i'm assuming that this requires the smallport fuel rail and maybe a new fuel line?) and modifying my harness to accept the smallport injectors? Any other parts/mods that i have to make in order to accept the smallport head?

Thanks!

The Robot Cow wrote:I've tried searching for a few days about details about a smallport swap but I couldn't really find a definite answer.
I'll be using my largeport electronics, tvis intake w/t3 adapter, 7 rib largeport bottom end with rwd parts.

I do know that i need to cap off the oil return line on the head, but what about the fuel injectors? Should i go ahead and source a set of smallport injectors(but i'm assuming that this requires the smallport fuel rail and maybe a new fuel line?) and modifying my harness to accept the smallport injectors? Any other parts/mods that i have to make in order to accept the smallport head?

Thanks!

Your largeport injectors and ECU should work just fine.
Your largeport cams, BTW, originally had a smidgen more lift and duration than the smallport cams, so you may want to switch those over.

When you get into an aftermarket ECU you might do well to find more modern injectors, which are new or remanufactured. Enjoi!

burdickjp wrote:
Your largeport injectors and ECU should work just fine.
Your largeport cams, BTW, originally had a smidgen more lift and duration than the smallport cams, so you may want to switch those over.

When you get into an aftermarket ECU you might do well to find more modern injectors, which are new or remanufactured. Enjoi!

Thanks!
I was thinking about switching my cams over, but i think i'll leave the stock smallport cams in untill i get poncams later on.

You will need a smallport fuel rail (works with bigport injectors).

Cheers... jondee86

**IF** you find you need more fuel then the stock injectors supply....

mid to late 1980s Honda Accord, Prelude with the 2.0i engines have beige jacketed low ohm injectors that are rated @ 240cc. Stock 4AGE injectors are either 185, or 210.

smallport injectors are high-ohm and rated @ 250cc.

ariel_86 wrote:smallport injectors are high-ohm and rated @ 240cc.

There is some confusion over this, no doubting they are high impedence but it is the cc thing.
Some say 235cc and others 250cc
Does anyone know the answer to this ?

My research suggests the green small port injectors are 250cc, based on the Nippon Denso part number and various online resources that claim to have flow tested or have original documentation to go from.

ariel_86 wrote:My research suggests the green small port injectors are 250cc, based on the Nippon Denso part number and various online resources that claim to have flow tested or have original documentation to go from.

Hope you understand that I'm not suggesting that you are wrong and if you are correct I will reset my ecu to 250cc injectors instead of 235cc

totta crolla wrote:Hope you understand that I'm not suggesting that you are wrong and if you are correct I will reset my ecu to 250cc injectors instead of 235cc

I understand sir and hope I didn't come across as argumentative.
Unfortunately, I can't recall how I found the specs I quoted, but I feel it can be replicated with some effort. I'm pretty sure I googled the part number visible on my injectors, 23250-16110, and also used a parts cross-reference & recommended OEM type replacement parts list through O'Reilly Auto Parts to verify the flow rate.

If I am wrong, I respectfully ask to see evidence that suggests the correct flow rates. I regret that I can't provide more concrete evidence to my claims.

Here's a pic of one of my injectors.