I am currently building an lsvtec for my 92 integra. Most of the build is covered and about to take off but there are a few questions that I have before beginning the build.
I purchased a 92 civic si hatch with a b18c1 from a 95 GSR. The car had a p30 ecu and utilized the GSR harness since the car was already obd1. I picked it up for a fairly cheap price due to the spun bearing. I have an A1 obd0 longblock. Here goes the questions…
I want to utilize the GSR harness yet I do have the a1 harness. I have a brand new alternator and starter for the a1. Is there any way I can use these with the GSR harness and will the starter fit the GSR transmission?
What other electrical issues will I have to deal with since I am using the obd0 block with an obd1 GSR harness?
I am not installing a knock sensor and therefore will have hondata do a delete and will be running a hondata s200. Should I opt for the p72 ecu rather than the p30 do to the butterfly issue?
Should the flywheel be the a1 or c1?
I am using…
GSR top end.
GSR rods and piston
ARP rod bolts and mains.
GSR water pump
GSR timing belt
GSR oil pump
Ls headers
Golden eagle conversion kit with head bolts
Any help or constructive criticism would be greatly appreciated.
B-series starters are interchangeable, the A1 starter will fit the GSR case.
I believe flywheels are the same weight between LS and GSR, though I could be wrong. But either one would work fine.
I may also be wrong about this, but I would use the harness that’s already in the car… then use a conversion harness at the ecu for obd0-obd1. When swapping harnesses, a lot of times you end up with more issues than the ones you are trying to solve with the new harness. I’d be interested to hear other users input on this one.
The ecu won’t matter as long as you are running a management system that can disable the butterfly valves (if that is indeed what you want.) But Hondata should be able to do that if I’m not mistaken.
I would seriously look into getting another header as the LS will hurt airflow significantly. But if you’re running stock cat and exhaust then it won’t matter much because the exhaust will also be a serious bottle-neck.
Like I said I’m not 100% on the harness options… because if you stay with the obd0 unit you’d need to change a few things around, buy an ecu adapter for an obd1 style, and also you would need a vtec sub-harness since yours is an LS harness.
But on the other hand the full engine harness swap might present other issues. Such as, on our cars the MAP sensor is firewall mounted, where on 94+ they are on the throttle body. So you have to splice/extend wires to utilize the 94+ throttlebody/MAP setup. Gah, I’m probably confusing you more, sorry about that lol. My recent build was in a '93 so thankfully it was already obd1.
Thank you very much. Everything you provided should prove to be useful though I am still unsure about the engine harness.
I bought the 92 integra as a shell. There is no engine harness. I just have the obd0 harness on the a1 block and the obd1 harness on the GSR block. The p30 is obd1 as well as the chassis harness.
[QUOTE=unified112;2160960]1) B-series starters are interchangeable, the A1 starter will fit the GSR case. – not true. obd1 vs 2 starters aren’t swappable.
I believe flywheels are the same weight between LS and GSR, though I could be wrong. But either one would work fine. - gsrs are slightly lighter.
I may also be wrong about this, but I would use the harness that’s already in the car… then use a conversion harness at the ecu for obd0-obd1. When swapping harnesses, a lot of times you end up with more issues than the ones you are trying to solve with the new harness. I’d be interested to hear other users input on this one. - since he’s going with vtec, it’d be easier to just use a vtec harness. as long as it’s an obd1 to obd1 swap, the plugs should be the same.
The ecu won’t matter as long as you are running a management system that can disable the butterfly valves (if that is indeed what you want.) But Hondata should be able to do that if I’m not mistaken. - all of them can do it. ECtune is the way to go imho.
I would seriously look into getting another header as the LS will hurt airflow significantly. But if you’re running stock cat and exhaust then it won’t matter much because the exhaust will also be a serious bottle-neck. - agreed. look into an exhaust system overhaul.
Like I said I’m not 100% on the harness options… because if you stay with the obd0 unit you’d need to change a few things around, buy an ecu adapter for an obd1 style, and also you would need a vtec sub-harness since yours is an LS harness.
But on the other hand the full engine harness swap might present other issues. Such as, on our cars the MAP sensor is firewall mounted, where on 94+ they are on the throttle body. So you have to splice/extend wires to utilize the 94+ throttlebody/MAP setup. Gah, I’m probably confusing you more, sorry about that lol. My recent build was in a '93 so thankfully it was already obd1.
What is the difference in starters? I was of the opinion that they were the same… learn somethin new every day! Lol.
Thanks for settin me straight on the flywheel also.
And yeah after reading that the motor was an obd0 motor I just assumed it was in an obd0 chassis. D’oh! Yeah it would more than likely be easiest to use an obd1 vtec harness if possible.
But there are doing to be a couple unused or different plugs, aren’t there? Such as needing the obd1 style thermostat housing/fan switch as the obd0 fan switch is in the back of the block, and is a different plug style. And the oil-temp switch in the b18a block that is not in 94+ GSR harnesses? Any conflics with the DA fusebox and DC harness??
Either way though, since you habe the obd1 gsr harness, it would be easiest to use that I think.
I’m a fan of the Neptune management system, but it depends on who is in your area and if someone local is a licensed dealer… easier/cheaper than running a Hondata setup. And I have zero experience with ECTune so I can’t really comment on that at all.
[QUOTE=unified112;2161110]What is the difference in starters? I was of the opinion that they were the same… learn somethin new every day! Lol.
Thanks for settin me straight on the flywheel also.
And yeah after reading that the motor was an obd0 motor I just assumed it was in an obd0 chassis. D’oh! Yeah it would more than likely be easiest to use an obd1 vtec harness if possible.
But there are doing to be a couple unused or different plugs, aren’t there? Such as needing the obd1 style thermostat housing/fan switch as the obd0 fan switch is in the back of the block, and is a different plug style. And the oil-temp switch in the b18a block that is not in 94+ GSR harnesses? Any conflics with the DA fusebox and DC harness??
Either way though, since you habe the obd1 gsr harness, it would be easiest to use that I think.
I’m a fan of the Neptune management system, but it depends on who is in your area and if someone local is a licensed dealer… easier/cheaper than running a Hondata setup. And I have zero experience with ECTune so I can’t really comment on that at all.[/QUOTE]
To be totally honest, that’s what i’ve always been told lol. I’ll go look here ina bit, i should have one of each downstairs. There are differences between the obd0 and obd1 harnesses, but the obd1 harnesses should be the same. the gsr one will have the provisions for vtec. the gsr harness will have extra plugs but you should be able to hook everything up and not have any issues. Neptune is cool, but ECTune is even easier and more user friendly. They are basically the same, ECtune has more features which some people seem to have issues with from time to time but it’s being updated and has great support. Also getting to where you need to be in the program is far easier with ECTune.
Don’t use the OBD0 engine harness, use some plugs off of it for misc sensors if needed.
Don’t use the EG/DC engine harness, use some plugs off of it for misc sensors if needed (e.g. vtec solenoid). While the EG/DC engine harness can be made to work it is far from a “bolt in” way to go. First of all, some critical components of the DA and EG/DC are different, such as fuse box and battery locations. This means that the connections for these items are different and will need to be modified to work in a DA. Second, the pins are different. We see this not as a DA vs EG/DC difference but as a vtec vs non-vtec G2 difference. Even an engine harness from a DB2 will not “bolt in” to a DA/DB1 engine harness and function properly. The extra (vtec) wires are not found in the main harness, and iirc there are actually a couple of different wires which are pinned to different locations on the connectors for where the engine and main harnesses meet. (*I have not researched these differences in a long time, so I’m a bit rusty, but the topics have been covered, so you can search and learn all the nitty-gritty details I don’t remember off the top of my head)
You will want to get an engine harness from a 92-93 rs/ls/gs, that will be the most straightforward way to do your swap.
Great info… that’s what I thought of during my last post, fusebox location differences between DC and DA. As you say they could be made to fit but aren’t really the ideal way to go about it.
From my reading and personal experiences it is indeed easier to stick with the correct harness for the chassis and just mod it to fit, swapping connectors or lengthening/shortening wires.
In my swap I just did, lsvtec in a '93 LS the wiring couldn’t have been easier, the only thing that was extended was the MAP sensor. Everything else plugged straight in. Then add a vtec subharness that you just pin-in to the ecu harness, and everything else was just stock.
As Colin made clear, the DC harness will work but since its not designed for our chassis, its by no means ideal. Maybe sell the complete GSR harness for some dough and get yourself the correct ls/gs/rs harness as said above me.
All of your help is much appreciated. I will most likely start a thread in the general discussion area after I get all the parts and machining done. The conversion kit arrived today. I’m waiting on…
Miscellaneous gaskets
Waterpump
Timing belt
Tensioner
Oil pump
Bearings
Rod and main bolts
Etc. Etc.
All together I am very excited about the build and now I just wish all my parts would arrive!