mustang 5.0 carb bolt pattern doesn't match intake?

[twin_turbo_mk3]

hi

so im converting my 91 mustang 5.0 to carb so i baught the following.

edelbrock performer rpm intake
edelbrock 600cfm carb. # 1405

so i try to bold it in for test fit but the bol pattersn are different. what gives?

i baught it thinking that since its both edelbrock it would match.

i could only bold 3 out of 4 bolts. do i need some sorth of spacer with two different bolt patter? i was uncer the impesion that a carb can be bolted to the intake directly.

 

[lang williams]

sounds like there's a flaw with the one of the two. either a bolt hole is off on the carb or the intake spacing on the studs is off. how much is it off by?

 

[twin_turbo_mk3]

sounds like there's a flaw with the one of the two. either a bolt hole is off on the carb or the intake spacing on the studs is off. how much is it off by?

i would say its off by about 2-3mm

is this a common flaws? i have research this two and noone mentioned this. do i have to use special bolts or something?

 

[93 LX]

I would think you have a bent stud...

 

[lang williams]

I would think you have a bent stud...

wow....i was making it too complicated...if they are used studs it could be. my experience with edelbrock has always been positive. american made quality stuff that doesn't have the flaws you get with the overseas made stuff.

 

[twin_turbo_mk3]

wow....i was making it too complicated...if they are used studs it could be. my experience with edelbrock has always been positive. american made quality stuff that doesn't have the flaws you get with the overseas made stuff.

i wish that was the case but i bought new studs today and it still doesnt match

 

[93 LX]

make sure the studs are indeed straight. Use a square to make sure. I have used NEW studs and after they are installed one didnt thread straight. A tap fixed it and the Capri runs great.

 

[rd]

Is it possible that the studs are in the postions for the Qjet layout?

Otherwise, if the holes are not straight it will cause the studs to not fit well.

 

[twin_turbo_mk3]

Is it possible that the studs are in the postions for the Qjet layout?

Otherwise, if the holes are not straight it will cause the studs to not fit well.

what is a qjet layout? how do i know its qjet?

and basically the two front holes and the passenger side one fit. the driver side back one doesn't fit.

seems that if i enlarge the bolt holes on the carb it would fit.

 

[85_SS_302_Coupe]

It probably has to do with how straight the holes are drilled in the intake for the studs. If one or more of the studs isn't perfectly straight up and down then you'll have problems.

Are the studs almost in a square pattern? A quadrajet would be wider in the rear than the front.

 

[lang williams]

i thought of that too but then thought i've never heard of a quadjet intake for a ford.

 

[twin_turbo_mk3]

It probably has to do with how straight the holes are drilled in the intake for the studs. If one or more of the studs isn't perfectly straight up and down then you'll have problems.

Are the studs almost in a square pattern? A quadrajet would be wider in the rear than the front.

thats not the case iether as i try to match the whole location withour bolting it just matching and the driverside back is just off. im thinking widening the carb hole to fit it since the other 3 fit perfect. since 3 hole matching pefect im assuming it will be straight.

 

[93 LX]

take the intake back.. defective...

 

[85_SS_302_Coupe]

Yeah i would say you got a jacked up intake.

Out of curiousity, and don't take this as an insult or anything...but are you putting the carb on in the right direction? You know the bolt pattern isn't perfectly square so if you turn the carb 90 degrees then the holes won't line up.

Yeah, dumb question but sometimes they have to be asked

 

[twin_turbo_mk3]

^^^ well i cant return it since i baught it of some guy used.

Yeah i would say you got a jacked up intake.

Out of curiousity, and don't take this as an insult or anything...but are you putting the carb on in the right direction? You know the bolt pattern isn't perfectly square so if you turn the carb 90 degrees then the holes won't line up.

Yeah, dumb question but sometimes they have to be asked

no worries i already tried to fit it all 4 ways lol. and basically teh only way i ca fit 3 bolts when i have the "edelbrock" label facing the front.

and heres what im talking about. View attachment 266426

 

[93 LX]

found this on the edelbrock site..

You must use Edelbrock Adapter #2732 when installing a
Performer Series carburetor on certain Edelbrock intake manifolds.
In those applications, install the adapter as shown (See Fig. 5).

http://www.edelbrock.com/automotive_new/misc/tech_center/install/1000/1405.pdf

 

[85_SS_302_Coupe]

Wow that's news to me, but then again i've never owned or used an Edel carb either. I bet you wouldn't have this issue with a Holley

 

[white 89 GT]

Do the throttle plates open all the way without hitting when the carb is sitting on the manifold.
Carb or manifold one of them is junk. I would never think about using one of those edlebrock carbs, the word performance does not apply to them.

 

[rd]

This is interesting info. I have an Edelbrock Performer RPM and a Holley intake on my Foxes and my Holleys fit fine.

I have a Performer and an Edelbrock 1406 on my Chevelle. It has the spread bore intake openings and dual bolt patterns (what I called the q jet pattern earler). It was a real pain in the but to find a carb to intake gasket for this. Even the Edelbrock tech guy got it wrong... twice. I ended up changing the stud positions. So there are some issues out there.

I would measure what you have, call Edelbrock and check on the situation and the spacer, and as a last resort, modify the holes.

 

[iapexl8r]

are all four butterfly valves on the carb the same size? if they are not you have a spread bore carb.. and need a square bore carb.