Which J&S safeguard is right for me ? - Honda Prelude Forum

Prelude Racer · 01-18-2003, 12:48 AM

Wassuperz fellow luders. As some of you know I got a 98 SH with a JRSC at 6 PSI. Just finally about a week ago got it to run correctly. Meaning getting the wiring installed properly

but anyway I am already looking to protecting my investment. First of is going to be a J&S safeguard. All this time I was thinking the the ultra safeguard 1 channel/2 channel combo was the one for me. but i have been told that since I i got a JRSC on my lude that i should get the safeguard version 1... is this right ? cooe thanks everyone

sharkcohen · 01-18-2003, 02:50 PM

The Ultra Safeguard V1 will be fine for your setup. The only reason you would ever need the V2 is if you needed a MAP limiter solution for your setup, as I did for my PMS system. If you will be running the stock JR electronics or decide later to change over to using larger injectors and a VAFC, hondata, or EMS, in all cases you would not need a MAP limiter.

Prelude Racer · 01-18-2003, 03:42 PM

okay cooe thanks shark... well i already have a vafc and i do plan to change over to larger injectors sometime in the future. first i want to take care of the possiblity of detonation then after i get the safeguard i want to move up into having proper fuel. so like stated before after the safeguard i will want bigger injectors, a efi pms, and any other fuel mods i may need such as a different fuel regulator other then the js one. but i just want to make sure buying then v1 safeguard won't cause me to run into a wall in the future with my plans thanks

Quaalude · 01-18-2003, 03:50 PM

Like sharkcohen said, the v1 will work perfect.

sharkcohen · 01-18-2003, 04:19 PM

Quote:

Originally posted by Prelude Racer
okay cooe thanks shark... well i already have a vafc and i do plan to change over to larger injectors sometime in the future. first i want to take care of the possiblity of detonation then after i get the safeguard i want to move up into having proper fuel. so like stated before after the safeguard i will want bigger injectors, a efi pms, and any other fuel mods i may need such as a different fuel regulator other then the js one. but i just want to make sure buying then v1 safeguard won't cause me to run into a wall in the future with my plans thanks

If your future plan includes an EFI PMS, then you might want to consider getting the V2, as the PMS does not include a feature to limit the MAP signal to the stock ECM. At least as far as I know. I did speak with Doug at EFI at the beginning of last summer and he said that they would be starting to include some sort of MAP limiter with the new PMSs, but I am not sure that they ever implemented that so you would need to check with them. If they have not, or you end up buying a used PMS (which are not uncommon on h-t.com and I suggest because the price of a new one is fairly expensive) then you should get the V2 so you have the MAP limiter solution when you finally do need it.

Or you could just save a bit now, get the V1, and later on if you ever need a MAP limiter you could pick up a missing link. Either route is fine.

Prelude Racer · 01-18-2003, 04:47 PM

remember i am a new at all this so .... what is a map limiter ? why would i need it ... so if i end up needing a map limiter there is a such thing as a missing link ? thanks shark

sharkcohen · 01-18-2003, 07:23 PM

Quote:

Originally posted by Prelude Racer
remember i am a new at all this so .... what is a map limiter ? why would i need it ... so if i end up needing a map limiter there is a such thing as a missing link ? thanks shark

MAP = manifold absolute pressure. The stock ECM will throw a code if it senses pressure higher than atmospheric. This, of course, will occur if you are running boost. The J&S V2 has a circuit in it that has an adjustable voltage limiter for the MAP signal from the MAP sensor. You cut the MAP sensor signal wire that runs to the ECM, run the sensor side to the V2, and run a wire from the V2 to the ECM side of the MAP signal wire. There is a potentiometer that allows you to adjust the maximum voltage that is allowed to the ECM. This is set with a voltmeter. This way, you can prevent the ECM from seeing the high voltages that would be produced by the MAP sensor under boost. A missing link is a similar electronic device, although I am not sure exactly how it works, but it is wired in the same way. I believe missing links run about $50.

Your current setup does not need a MAP limiter because the JR electronics intercept the MAP signal and use it to determine if there is boost. Hondata and the EMS do not have a problem seeing boost from the MAP sensor. The VAFC uses the MAP signal as well, so one would not want a MAP limiter on a VAFC setup.

Prelude Racer · 01-18-2003, 08:24 PM

cooe shark u are the man... may i ask what kind of J&S do you have ?

sharkcohen · 01-18-2003, 08:58 PM

I have the V2 because I needed the MAP limiter.

Prelude Racer · 01-18-2003, 10:07 PM

why do u need the map limiter... ?? not using the JR ems ?

sharkcohen · 01-18-2003, 10:12 PM

LOL, no, I never installed that thing. I'm running the EFI PMS and 550 cc injectors. I won't allow the JR black box near my car.

Prelude Racer · 01-18-2003, 10:46 PM

haha ya ..... thats funny.... damn that jr black box.... my car now is running lean, another issue i am going to have to address.... i took out my spark plugs and they are white.... i am blaming that black box hahah

sharkcohen · 01-18-2003, 11:12 PM

Do you have an in cabin fuel pressure gauge? Your setup should not be without one. You may be running lean because your peak pressures under boost are too low.

Prelude Racer · 01-18-2003, 11:14 PM

nope but i will soon i put my car in the garage and just goin to leave it alone its not my daily driver... after i get this gauge what showed it be at ... at what rpm ? thanks shark

sharkcohen · 01-18-2003, 11:16 PM

You really need an in cabin fuel pressure gauge for your current setup. Do a search, proper fuel pressures for the JRSC has been covered numerous times.

Prelude Racer · 01-19-2003, 06:07 PM

is the map limiter the same thing as the map sensor that sits on top of the throttle body ?

sharkcohen · 01-19-2003, 06:20 PM

No. The MAP sensor is what senses manifold pressure. Remember, MAP stands for manifold absolute pressure. An electronic MAP limiter, as I explained above, limits the voltage output from the MAP sensor before the signal reaches the ecu. Options besides a MAP limiter are check valves and the missing link. Check valves are placed in the rubber line connected to the MAP sensor to prevent the MAP sensor from sensing boost. I'm not sure how exactly a missing link works, but you can find info about it by doing a search.

In any case, if you need some way of preventing the ecu from "seeing" boost pressure, IMHO the best way to do that is use a J&S V2.