hello, i need some help wiring crossfire injection hood flaps. the hoods from a 82 the car is a 89 ecu 8647 . Is there something in the curcit that will send a ground at wot. or send 12 volts at wot . i was also wondering if anyone knows the part # of the manifold vacuum switch used on a 84 trans am with carb and air induction. im thinking i might have to use that vacuum switch if my ecu will not send a ground at wot .

 

anybody ?

 

i have some wiring diagrams etc but im not all that smart so i have some questions.
what are hood flaps for crossfire injection. how did you get hood from an 84 but with cross fire from 89. in 89 they were using maf tpi or tbi. did they use crossfire injection in 89?
and what does WOT mean?

 

in 82 they offered the indy 500 pace car with cowl indution hood flaps . or call it ram air if u like... they are flaps that open up in the hood that force air in to the air breather . alot like the 69 camaro ram air . i built the car u see there in the pic i installed it from a 82 pace car . the car is a 89 . pretty simple to understand i think. however i don't recommend the cross fire injection unless you are ready to do some work to the intake . which is what i done . cuting the runners in the plum and porting the intake to match the runners in the heads . and rebuilding the tbi's .this includes installing in bushing for the thorttle shafts. after that u will have a good crossfire injection system once u blance the tbi's ..not as easy as it sounds . in 84 u could get a trams am with a 305 and carb . that offered the blister hood . whiched used a vacuum switch from the manifold .anybody know the part #?? when vacuum was lost it would complete the circuit. and open the flaps.

 

i didn't get anything from a 84 . but i would like to get the vacuum switch from a 84 trans am that opens the flap. .actually 82-84 if my not mistaken or if someone know how to send a ground at wot from a 89 ecu 8647 let me know please ..wot is wide open thorttle. please excuss the spelling im more of a hands on type of guy lol .

 

if im not mistaken some 2nd or 1st gens had something that opened up the cowl. you can do the research lol
----------------
or if you wanted to itd be no trouble to rig up a switch that closes at wot. do you have any pics of the flaps from behind?

 

already looked at it . but i app it

 

I found this in the GM parts and illustration catalog. It shows:
SWITCH. Thermo Vacuum (EFE & EFE Combinations)
part # 3043015

 

great thanks dude . i will take a look at that . did u sell ur crossfire yet ?
----------
no thats not it but thanks for the try .

 

I didn't see any other listing that matched what you're looking for. I'll try to look some more.

Not yet. Still hoping someone needs it. Going up on ebay soon.

 

it's gm part # 25036589. which was replaced the a different part but same part #which they don't give a fit for. and doesn't look anything like the vacuum switch i need. it looks more like a presure which . so basicly it's a impossible possibility that i will find a new replacement. ebay or junkyard maybe .

 

well i could set up a relay that will close at wot .if i can find a ground from the ecu at wot. i was hoping the ac clutch but no luck there. and to be honest im lost when it come to making a circuit. its the ground at wot thats my problem. the 89 ecu 8647 don't have one that i know of but i been wrong before.

 

for the love of all that is holly and jolly i find a vacuum switch !! that complete's a ground at low vacuum . anybody with the same problem let me know and i will share .

 

hi, please go ahead and let us know which vac switch you used. and also what ratings/specifications it has such as opening at X vacuum.
i can post some wiring diagrams from my 84 firebird GM shop manual if you like. i remember they also used to wire a 140°F switch in between so the cowl induction would only be active once the engine was warmed up at least a bit

 

the vacuum switch i found was used on 74and up dodge cars and trucks. it is called the fuel pacer vacuum switch . what it did was turn on a light mounted on the left front fender.and later models in the dash.up to 81 for sure. maybe longer but it was a option. it is set at the factory to close send current at 3-5 pounds vacuum . it is dodge part #3746945...it is also adjustable. i was thinking about coming off of the fuel pump relay. but i would love to see those diagrams. this switch looks some what like the factory switch used on 84 trans am .

 

thanks for the info!

do you by chance have any numbers or an approximate idea how much vac our engines are pulling at idle? 3-5 psi would translate to about 6-10 inHg, i think between 6 and 8 would be good enough for this hood flapper application. i'll get you the diagrams once i get a chance to get it from my shop. not sure if they used the same parts for the camaro hoods though. maybe i can also look up how much vac the stock switch needed.

 

sure no problem . my car ideals at 21hg and i said psi but the switch is set at 3-5 hg. but it's adjustable. i installed mine yesterday. the flaps will only open when u step on it. they close when u back off of it.. u can adjust it to 10 if u would like them open more often and or sooner. there's really no performance gain that i can tell. but it's still a rare kool peice. it works on mine it will work for u > good luck .