Diablosport Forums

I ordered a 85mm throttle bodt for my 5.7L hemi. In the product description it says tuning "may not be" necessary? Is this something I need to have a dyno shop do? or can I tweek the custom tune I allready have?

Depends...you may have to see how it runs once you get it.

I hope not the Modern Muscle one? Thats been proven to not be worth the throttle body its made of. Made like 3hp on the dyno on the 6.1, which means that if you put it on the 5.7, which doesn't need the extra air, you'll get nothing from it. The 90mm from Arrington on the other hand has shown to be quite effective when paired with a tune. I believe something like 18hp on the 5.7 and 23 on the 6.1. Nice power, but for a grand I'd hope it would be effective.

I've seen a dyno sheet where the MM 85mm shows +8~12hp/tq gains. I suppose your results may vary. I think the +3 was another bored over TB from another vendor.

dcram71 wrote:I've seen a dyno sheet where the MM 85mm shows +8~12hp/tq gains. I suppose your results may vary. I think the +3 was another bored over TB from another vendor.

I've seen this same dyno info! maybe the 6.1 run better with the 90mm rather than the 85? I spke with a Extremely reputibale Dyno Tuner who said this was the better way to go between the two TBs.

Oh well if it is a waste of money won't be the most I've ever lost?

Ummm, what size is the port into the manifold immediately behind the TB? and maybe the diameter of your air intake tube also.

Quick wrote:Ummm, what size is the port into the manifold immediately behind the TB? and maybe the diameter of your air intake tube also.

Stock 5.7 plastic manifold Air Hammer CAI

I'm not familiar with the 5.7 manifold or the Air Hammer you have. It's just that if the diameter is straight through now, opening up the middle won't buy you anything. If the Air Hammer is 4" diameter at the end right now and the rubber connector steps it down to the stock TB then you'd only need a different connector. The manifold might be more involved. With the 90 mm TB's on the 6.1's you don't get anything unless you get the manifold port bored out as well (a bit tricky to do and get the TB to seal correctly. If you don't you might even lose a little bit since the air would be coming through the larger TB and running into that flat lip of the smaller opening on the manifold causing turbulence and disrupting the air flow. Those who have done all the above are saying they are seeing gains but they're still wrestling with the tuning. Especially surging at idle and partial throttle.