Question about flow potential of explorer vs. cobra

[84convertablegt]

I was looking at the flow data for the cobra vs. explorer intake in the sticky thread on here. It appears that the 94-95 cobra does flow more than the explorer intake. I was wondering how this is? does this take into account the lower or the upper only, or both together. The reason I ask is because I have a 94-95 cobra lower that has been port matched to a 1250 gasket and Im gonna use an explorer upper instead of my 95 cobra upper to go to the 93 style throttle body. I dont want to loose flow obviously, Im looking to increase throttle response and improve appearance. I cant see why the cobra upper would flow more than the explorer upper since there is less air travel and they are basically the same casting. Can anyone shed some light on my situation. I have AFR 165 heads and really dont wanna waste potention. An edelbrock or the like is not possible. BTW, Ill be using an accufab 70mm egr spacer and tb.

 

[Joes95GT]

Whatever you saw was pretty inaccurate, IMO. I have never personally flow tested anything, but I have seen flow comparisons where the Exploder flowed equal amounts (within ~3%) of the Cobra.

The restriction in any of the GT40 style manifolds is in the lower manifold, anyway. Uppers shouldn't make a difference.

PS - flow numbers in an intake don't mean ****.

Joe

 

[84convertablegt]

thats good to hear, especially since my lower has been ported and matched. anyone else care to comment on this.

 

[tmoss]

That sticky should be edited and that incorrect early info removed.............check this out..........

 

[84convertablegt]

wow, that is definately interesting. i guess i dont have to be worried about losing anything then. In fact, i will probably gain some throttle response and maybe a few hp.

 

[Zero Signal]

They say 28" of water shouldn't it be 28" Hg? Probably writer error. Interesting that the explorer flowed slightly more in that test than the cobra, but probably random variation in the test. Still that test shows that they are basicly identical.

On another note . . . I did some mild port work on my Explorer lower this last week. I didn't want to get into any welding so I stuck with some mild massaging of the sharper bends to help prevent any BL-separation effects. Hopefully it works out ok.

 

[tmoss]

Interesting that the explorer flowed slightly more in that test than the cobra, but probably random variation in the test.

Or casting variances............

 

[RIO5.0]

Tom...here's one for ya....I just swapped on a GT40 upper using the same lower you ported and a 1" spacer....Power is different for sure...thing is pulls alot quicker to redline...thought it was odd when I first got into it...but sure as chit its there...
Would the GT40 upper change things like that?? I have run all the FRPP uppers and did nada but this swap...There's an obvious difference...I thought the 1" spacer was gonna kill it somehow?? Seems the opposite to me...
I cant figure out if the uppers that much better or if the spacer helped out??
I wish I had access to dyno it and see where the curve changed...something did....It woke it up some for sure...
Any thoughts.....

 

[tmoss]

Id say the spacer more than anything else - adding length shifts the torque curve with a bias towards the low end. That and the differences that exist from upper-to-upper also. There is less in the tubular version, but it does have cast componants too. I've seen significant core shift (for ultimate airflow considerations) in some cast uppers before. I know your a thorough guy though and I'd bet you looked for that in your cast uppers.

 

[Zero Signal]

I did notice that the explorer upper doesn't line up perfectly with the lower. I plan to port match the upper to the lower and match the gaskets and spacer accordingly before I put it back on. It was offset from the lower by at least .125" on every hole