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Help with MSD 2 step launch control pn 8739 install

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4.4K views 16 replies 7 participants last post by  importcustomx  
#1 ·
i have a 1990 crx d16a6 with a CDI Street fire ignition box and i need help installing my new 2 step launch control. i am a noob at these stuff and i want it install to my clutch instead of the brake so i could use the clutch pedal for launch. any suggestions besides the ecu chipping that has a built in launch control?? i'm in minnesota in a small town where no body wnats to chip ecu.
 
#2 ·
you could send your ecu to wicked innovation. they do great work

wickedinnovation.net

thats Downest and M@miner.

they will help you out. you can sell all the MSD stuff and get a quick tune on ur ecu.

boom done.

thats what i did. i set my launch control at 3800. and my check engine light is my shift light which pops up at 6850rpms.
 
#6 ·
MSD 6AL with a 8739 will need to be wired thru a clutch switch.

IIRC when the wire from the 8739 sees 12v, you are on the low chip (module 1), when not powered it becomes a normal revlimiter (module 2) on the high chip.

While that setup will work, I don't like dealing with chips to set launch rpm.

I would use #8672 in place of a chip on module 1 and have it mounted near the driver. That way you can adjust launch rpm as needed. Say someone in front of oil oils down, you might need a lower rpm if track is just cleaned up, or a HIGHER rpm if after cleanup they spray the line with VHT.

There is another adjustable module that I was planning on using, #8735, I can adjust in 100 rpm steps, it also has a burnout RPM setting via chip, say 5000 or 6000 rpm for me.

To help drag racers achieve even more consistency, our engineers have incorporated an adjustable low rpm stage into a Three Step Module Selector! This allows you to make adjustments in 100 rpm increments from the driver's seat! The Launch Control Module features a shielded harness for increased protection against EMI so it can be mounted within easy reach of the driver. This way, as track conditions change while you're waiting in the staging lanes, you can easily compensate the launch rpm. The Launch Control also features two other rpm limits; one for top end overrev protection and another to use during the burnout to achieve consistent tire temperatures. These limits are adjustable with MSD's plug-in modules. No rpm modules are supplied.
As far as the 6AL help ignition, it only helps by quicker startups, OEM ignition is just fone up to 400 whp....or more.
 
#10 ·
I posted that, but seems one of my edits didn't go thru.

With a chipped ecu you have to carry a laptop with you to make the changes, something you cannot do once you're near the burnout box.

With the setup I'll be running I'll be able to adjust right before staging if needed. While this might be extreme for most, I'll be running points series next year at local 1/4 track, bracket racing for points AND money.

Yes, it is needed to be deadly consistent.

old .500 tree

Image


AMSOIL STREET CLASS RULES

* E.T. break 12.00 - 19.99 *
* Slicks permitted *
* Open headers permitted *
* Helmet required for 13.99 and quicker(Snell 2000 or newer) *
* Master cutoff switch required if the battery has been relocated to the trunk area *
* Seat belt mandatory *
* No shorts or sleeveless shirts *
* Cooling system overflow/catch can required *
* Driveshaft loop required if running 13.99 or quicker AND utilizing slicks (not required if running street tires) *
* One line loc only permitted, and only on non-drive wheels *
 
#11 ·
hey thanks alot everybody. i think i'm going to listen to IMPORTCUSTOMX and go with the chip tuning. Mista Bone, i think there is a way for the msd box or the street fire ignition cdi box to work with your stock ignition. the street fire box is installed on my stock ignition and i didnt had to do the external conversion. my car did came wth the external msd coils but i removed it because it was messing with my ignition when i first bought the car in 07.

i guess i probably will return my msd launch control to carquest and probably go with the ecu tuning. hope they tune the ecu so i would be able to use the clutch to launch the car instead of my brakes. i really dont understand how you could use the clutch with the launch control if its cable? is there a way that you could do that beside the msd? i'm going to be calling msd and see what they say about the installations. sorry for the late replys. i wasnt online to check the site.
 
#12 ·
Mista Bone said:
I posted that, but seems one of my edits didn't go thru.

With a chipped ecu you have to carry a laptop with you to make the changes, something you cannot do once you're near the burnout box.

With the setup I'll be running I'll be able to adjust right before staging if needed. While this might be extreme for most, I'll be running points series next year at local 1/4 track, bracket racing for points AND money.
With NepTune you can change your launch point on the fly if you use the TPS based 2-step.
 
#13 ·
Depending on the system you tune with, you can do clutch based launch control (you have to wire the clutch switch to an input on the ecu), variable tps based (holds at a point defined by a tps threshold), or speed based (bsaed on vss).

M@
 
#15 ·
Mista Bone said:
crxvtec91 said:
I assume you have little exp. with MSD products. While our motors don't need a stronger ignition, MSD offers other advantages with RPM and Timing control.

Esp. if you are running multiple stages of nitrous or locked out ignition timing, like Bisi did on the CRX.
When I speak of Msd for a honda it is always in reference to there igition systems. I have no need to by anything else from them when my ecu will take care of it.
 
#16 ·
thanks alot that answer my question and i'm going to return the msd launch control. i called the msd before i bought the box and they referred me to that 8739 box and i looked at the wires and think to myself that i dont think its the right wire to wire it to my car.

yes i do want to use a launch control with my clutch instead of my brakes because its manual and it would be nice if it works out. ill give both company a call though. the msd and the neptune tuning to cehck the pricing and the chipp ecus
 
#17 ·
No need to call neptune..depending on where you live i would call a local neptune dealer.

Call wicked Innovation...Tom & Matt will help you out.
they setup my ecu and launch control etc.

website link is in my signature.