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Hpi throttle body fitment issue , somebody please help me figure this out .

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Old May 28, 2016 | 07:20 PM
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Default Hpi throttle body fitment issue , somebody please help me figure this out .

Installed a tman performance 107 kit with his pro touring elite heads. Today I attempted to complete what I thought was going to be a 1 hr job and install my newly purched hpi 55mm throttle body and 5.3 injectors. For whatever reason I can't get the manifold to fit. As in I can't squeeze the intake manifold deep enough between the heads to get the bolt holes on the flanges to line up. I can get the stock tb back in but not the new hpi unit . It almost seems the manifold part of the unit is too wide to fit between my heads . Did a Google search and nothing seems to pop up as far as this being a problem. Has anyone encountered this problem and if so how did you rectify it ? Any help or suggestions would be greatly appreciated. Thanks in advance .
 
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Old May 28, 2016 | 07:59 PM
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Cool Measure it !!

Have you measure the two manifolds too see what the difference is ??? then call HPI ...tell them what you have ...you might what to measure the outlet size of the manifold (ID) and then the inlet of the heads and see what that difference is too ,,,cuz HPI will ask you that also ...(ID size of intake ports ) ...if there is nothing they will do ...and if you really want to use the new one ...break out the file and start taking some off each side of the manifold !!!

we have done this many times ...just do a little at the time ...fit it up ...till you get it !!
be sure that when you think your getting close to the final fit ...bolt up the air filter backing plate to the manifold also as to keep everything inline .!!! dont worry ...you can do it ,,just takes a little time !!!

Welcome to the hot rodding world...
i think they call this a "custom fit" , or "one off" ...in the custom world
 

Last edited by springers4ever; May 28, 2016 at 08:08 PM.
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Old May 28, 2016 | 08:59 PM
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Thanks for your quick response . I communicated back and forth between tman and hpi several times during the initial purchase to make sure or at least try and make sure I had all my i'so dotted and t's crossed because these hpi throttle bodies are pretty pricey. Upon hpi recommendation I finally settled on a 55mm throttle body with the 58mm manifold . Without taking my heads off and putting them back on around the tb/manifold I just dont see how it would fit. I can't squeeze it in deep enough to get the front bolt holes even close to lining up. Is this a common problem ? Filing / Sanding the runners down on the manifold seems like the only viable option. I guess I was just expecting more for the $800 I spent . Seems ridiculous to spend that kind of coin and have to take a file to something.
 
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Old May 28, 2016 | 10:07 PM
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I had to remove .015 on each side to make it fit. You need a minimum of .005 between the intake and head on each side.
 
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Old May 28, 2016 | 10:14 PM
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I guess I'm gonna have to get the file out it sounds like . Just seems crazy that for the money people are dishing out that hpi hasn't a dressed this issue. So just to double check... I need to file equal amounts off each outlet runner of my intake manifold until I can slide the manifold deep enough to align the bolt holes ?
 

Last edited by Gesjr6; May 28, 2016 at 10:18 PM.
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Old May 28, 2016 | 10:21 PM
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Cool Call um again !!!

Originally Posted by Gesjr6
Thanks for your quick response . I communicated back and forth between tman and hpi several times during the initial purchase to make sure or at least try and make sure I had all my i'so dotted and t's crossed because these hpi throttle bodies are pretty pricey. Upon hpi recommendation I finally settled on a 55mm throttle body with the 58mm manifold . Without taking my heads off and putting them back on around the tb/manifold I just dont see how it would fit. I can't squeeze it in deep enough to get the front bolt holes even close to lining up. Is this a common problem ? Filing / Sanding the runners down on the manifold seems like the only viable option. I guess I was just expecting more for the $800 I spent . Seems ridiculous to spend that kind of coin and have to take a file to something.
You are right about that !!! but you should call first ...as they make some manifolds longer to fit heads that are milled down alot or cylinders with low deck heights ...etc...they may have sent you the wrong one !!!...


We know and understand your concern ...and frankly ...you have every right to feel that way ...just dont let it fog your final goal ...everyday things change and one needs to "roll with the changes" ...
and if you feel that this is the manufacture issue ...then you need to Call um up on it ...Everyday ...every hour ...!!! send it back and demand your hard earned $$$ back ...then you can send your stock TB off and have it punch to a 52mm ...and it will "bolt on " as you stated earlier !!! ...
just dont give up !!!
make them own up ...or give you your $$$ back !!!
Good luck ...let us know what way you end up going !!!
 

Last edited by springers4ever; May 28, 2016 at 10:28 PM.
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Old May 28, 2016 | 10:41 PM
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Thanks for the replies . I am a bit overly frustrated today . The last stages of this build have been a bitch. Everything was going smooth then at about the 450 mile mark of my 500 mile break in period I developed a tick almost a knock. We traced it to a rocker issue so i dropped close to a grand on s&s roller rockers and premium lifters. This forced me to cancel my scheduled dyno tune I had been waiting a month for . I figured while tearing back into the bike I would pony up for the new tb as well now I've run into this problem and of course it's memorial day wkend. I'm scheduled to have it dynoed on Tuesday so I hate to cancel again and wait another month. Dyno time in my area is hard to get this time of yr. I hate to go back to stock ,have it dynoed and find out from hpi that it's a common problem and they tell me to modify it to make it fit . At the same time I hate to modify it and then find out something is not rite and I messed up a manifold that I now can't return .
 
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Old May 28, 2016 | 11:02 PM
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Cool Tune it later ...

Originally Posted by Gesjr6
Thanks for the replies . I am a bit overly frustrated today . The last stages of this build have been a bitch. Everything was going smooth then at about the 450 mile mark of my 500 mile break in period I developed a tick almost a knock. We traced it to a rocker issue so i dropped close to a grand on s&s roller rockers and premium lifters. This forced me to cancel my scheduled dyno tune I had been waiting a month for . I figured while tearing back into the bike I would pony up for the new tb as well now I've run into this problem and of course it's memorial day wkend. I'm scheduled to have it dynoed on Tuesday so I hate to cancel again and wait another month. Dyno time in my area is hard to get this time of yr. I hate to go back to stock ,have it dynoed and find out from hpi that it's a common problem and they tell me to modify it to make it fit . At the same time I hate to modify it and then find out something is not rite and I messed up a manifold that I now can't return .
cancel the tune ...put the stock one on ....and ride it slow and finish the break in over this holiday weekend ...or till you hear from HPI next week ...you can figure it won't be until the following week at least before having a replacement in hand ...
 
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Old May 28, 2016 | 11:16 PM
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Thanks springer. That is no doubt good advice. I'm pretty impatient by nature coupled with being pissed off that I struggled for hrs with this darn thing so I just want to start filing away on it until I can make it fit . That little voice in the back of my head somewhere is telling me to listen to springer as he is the voice of reason tho.
 
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Old May 29, 2016 | 03:54 AM
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do you know if the heads were decked and if so by how much? this can make the intake hard to fit.
some even bolt them on loose before torquing down the heads.

this may or may not be your issue as you said the stock intake fits.....

mine were shaved around 0.037" and my zippers intake fitted easily
 
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