possible spark knock at wot

fastgtfairlane

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Apr 7, 2006

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Oct 21, 2007

#1

• Oct 21, 2007

• #1

alright, i was really bored friday and decided to make some modifications to my throttle body. i saw a pic of a car that had the 94-95 tb on his car with out the elbow. so i modified my intake manifold and made a plate to block the egr hole on the tb flange. anyhow got it it all bolted up. i have a typhoon intake and taking the upper off the gasket ripped up. so i used some rtv on the surface. i set it up and let it sit for about 45min before i put the upper on so it wouldnt all squeeze out when i torqued it down. while the upper was off i took the end plate off and cleaned up some of the casting inside the intake. gasket also came apart. put some rtv on it too. anyways, at wot it is spark knocking only in first and second gear. in 5th at wot it doesnt spark knock. im thinking i may have a vacuum leak but not sure. gimme all of your thoughts.

with the tb mod, it turned out pretty well. i will post some pics.

 

SublimeRT

Member

Jan 25, 2003

230

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Clarksville, TN

Oct 21, 2007

#2

• Oct 21, 2007

• #2

Could be a vacuum leak like you stated. RTV should really not be used as a gasket substitute. So many people over do it with that stuff.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

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Oct 21, 2007

#3

• Oct 21, 2007

• #3

Was the product used sensor-safe?

 

fastgtfairlane

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Apr 7, 2006

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Oct 21, 2007

#4

• Oct 21, 2007

• #4

i know that rtv is not a real gasket replacement. there was nowhere close to get an edelbrock gasket for the intake.

the rtv i used was sensor safe. i got it in the caulk gun tube so it would be a clean and neat job. i put a small bead all around the flat surface then smoothed it out with my finger and let it kinda setup before i put it together so it wouldnt squeeze out when i tightend the intake down. i havnt tried spraying carb cleaner around yet. will try that tomorrow. the wierd thing is that it idles fine and runs fine just at wot it spark knocks.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

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Oct 21, 2007

#5

• Oct 21, 2007

• #5

Gotcha on the RTV being sensor safe. It was worth confirming.

Did anything change with the MAF or area around the MAF?

 

go-stang5.0

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Jan 27, 2003

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Glenview,Il

Oct 22, 2007

#6

• Oct 22, 2007

• #6

Did you remove the egr doing this or was it already removed. I ask because people hae removed their egr and devoloped knock issues. The egr actually richens up the mixture and reduces possible knock. Some people have removed it problem free while others have had knock. The only way to remove it properly is to tune it out of the cpu with a custom tune, tweecer, etc. This may not apply to you but you didnt specify so I'm just throwing stuff out there.

 

fastgtfairlane

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Apr 7, 2006

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Oct 22, 2007

#7

• Oct 22, 2007

• #7

right on with the sensor safe rtv. i had to change the maf routing to look like the fox cai. i have a c&l mass air so i to run my old cai i cut the bracket off and got a hose coupler and used it. when i moved the tb i just used the 90 degree bend after the tb and used the pipe that used to be before the mass air that holds the iat after that, then put the mass air then the filter. its a temporary thing until i make my new cai.

 

fastgtfairlane

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Apr 7, 2006

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Oct 22, 2007

#8

• Oct 22, 2007

• #8

the egr was already removed from the car. the car did have a low rpm detonation just after the egr was removed but was able to remedy that problem with changing the timing from 16 to 15 degrees. eventually i will get a proper tune to take care of that and the timing retard between shifts

 

go-stang5.0

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Glenview,Il

Oct 22, 2007

#9

• Oct 22, 2007

• #9

Ok so thats not the issue then....well it was worth a shot.

 

fastgtfairlane

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Apr 7, 2006

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Oct 23, 2007

#10

• Oct 23, 2007

• #10

well after making a 3 hour round trip to holcomb motorsports to buy the plenum gaskets, i figured out what it was. not thinking it through before i made that trip, i didnt put 2 and 2 together. everytime that the car would spark knock i would smell burnt oil. after i got the gaskets i began taking the vacuum lines off and getting ready to pull the plenum off. i noticed that the new hose i got for the pcv valve was too big for the fitting. those dooshbags at advance gave me too big a hose. after i noticed how loose it was i put a clamp on the fitting side and a clamp on the pcv valve. put everything back together and test drove the car. it had better throttle response, and noticeably more power and best of all, no spark knock. i was super stoked that i didnt have to pull the plenum off. if i ever need to take it off again, at least now i have the gaskets.


thanks for your suggestions, it is appreciated very much

 

SublimeRT

Member

Jan 25, 2003

230

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Clarksville, TN

Oct 23, 2007

#11

• Oct 23, 2007

• #11

Cool man, glad you got it figured out. I didn't mean to sound like a dick about the RTV if I did. At least you have some spare gaskets now. That's always a good thing.

 

fastgtfairlane

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Apr 7, 2006

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Oct 24, 2007

#12

• Oct 24, 2007

• #12

i didnt think you sounded like a dick about the rtv. honestly i thought that was the problem too. i would prefer gaskets over the rtv any day but didnt have any so i didnt have much of a choice. but none the less atleast i have a leftover set you u said. i will get some pics of my new setup. still not sure it was worth all the hassle but its done. im gonna make a home made cai for it but my old one will work for now.