ECU help!

I just purchased a 93 GS-R with a “poor mans type r”. It consist of a b18c1 block, PR3 head, ITR intake manifold, and all OEM ITR internals minus the crank. The motor is mated with the 93 GS-R YS1. I am currently running on the stock p61. (The previous owner was running a p28 chipped with a hondata s300 running on a Type R base map un-tuned) I want to run it on a Type R base map also to get out the motors potential. (I am not tracking this car, it is more a less a weekend driver occasionally a weekday when needed) I am new to understanding ECU set ups and programming so any help/ education/ or guidance is much appreciated. I live in an area where emissions is required so that is a consideration. Cost is also a big consideration as of right now. From the research that I have done, I think that I roughly have 3 options:

  1. Run a USDM P73 with a OBD2 to OBD1 jumper harness.

  2. Run a JDM P73 with a OBD2 to OBD1 jumper harness. (I have read that this ECU is a OBD1 in an OBD2 case. I am not sure what I will need to do to make this set up work. I also vaguely recall coming across some differences in the JDM ECU vs the USDM ECU. I am not sure how that would impact my motor if I were to go with this concept. (I can purchase a JDM P73 locally for $150)

  3. Run a P28 chipped with the Hondata s300 and run this on a Type R base map. (I know that I am looking at roughly $600-$700 for this set up which I can not afford currently)

I have the option to purchase a P28 chipped with Chrome and run on Tpye R base map for $125 locally. I have read that there are a lot of issues with Chrome though. I dont want to deal with any issues if this is the case.

I also have an extra virgin p61 that I could possibly have chipped. I just don’t have the funds for the chip currently. Any suggestions for the best chip if I do go this route?

Any help is greatly appreciated!

40+ views and no comments. I guess I am striking out here. Am I not including enough information for guidance?

Not too many guys on here with a lot of ECU knowledge, plus with the holiday you gotta assume there are a lot of people busy or out of town.

I don’t think you should consider using an OBD2 ecu unless you’re ready to do the extra work involved - for example you’ll need to install the crank angle sensor and wire that up. I believe there are some other minor changes. Also, this would be an “OBD1 to OBD2” conversion harness, not vice versa.

Sounds like perhaps this purchase wasn’t the right one to make if you didn’t have the money for the correct ECU/tuning. But based on your options I’d suggest the Crome ECU you mentioned. Not sure what you’ve heard about Crome but I’ve never heard anything bad and have been using it for years. I’d like to switch to Hondata eventually but for now my tuner has no problem with Crome and my engine runs great. I would HIGHLY recommend getting an actual custom dyno tune as soon as you can. It’s well worth the money.


Thank you for replying and your input. I believe I am going to go the route of the P28 chipped with chrome on a Type R base map for now and eventually have it tuned. In time I will go for a P28 chipped with hondata S300 on a Type R base map and have it tuned when the funds are there. As I mentioned before, I am not tracking this car or going forced induction. I am going to keep it N/A with the current upgrades (i.e. CAI, Headers, and Exhaust). It will be a weekend driver and an occasional week day driver. I have a buddy that has a 93 LS Turbo and his ecu is chipped with chrome. He hasn’t had any problems with it.

useful and interesting article, found a lot of useful information, glad to join your community

Did the original owner not sell the ecu with the car? For simplicity sake I think the p28 with s300 is your best option. Plug and play for the most part, user friendly and tons of features. Might be pricey on the buy in cost but you will save this in time and money with jumper harnesses a the headaches inherently within.