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Head question...


SASPEEDRACER24

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Was looking at the rules for the Sportmods for a friend of mine and saw which heads were legal for them. Is the EQ IMCA stamped head the best option because if having a clean aftermarket casting or is there much difference between that and the 487x 441 993 heads. Just wondering... Thanks ahead of time...

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Was looking at the rules for the Sportmods for a friend of mine and saw which heads were legal for them. Is the EQ IMCA stamped head the best option because if having a clean aftermarket casting or is there much difference between that and the 487x 441 993 heads. Just wondering... Thanks ahead of time...

 

My understanding is the EQ head (out of the box) is supposed to be equivalent to a 487x. The problem is that these days, good 487x's are getting hard to find. IF, (or when) I am in need of new heads, I will be moving over to the new EQ heads, instead of investing all the time in finding, and then preparing a set of 20 year old castings.

 

My suggesting to get the maximum potentional out of the heads, is to get them from someone who knows how to make them work. I would suggest Spreen Racing Engines!

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Was looking at the rules for the Sportmods for a friend of mine and saw which heads were legal for them. Is the EQ IMCA stamped head the best option because if having a clean aftermarket casting or is there much difference between that and the 487x 441 993 heads. Just wondering... Thanks ahead of time...

 

My understanding is the EQ head (out of the box) is supposed to be equivalent to a 487x. The problem is that these days, good 487x's are getting hard to find. IF, (or when) I am in need of new heads, I will be moving over to the new EQ heads, instead of investing all the time in finding, and then preparing a set of 20 year old castings.

 

My suggesting to get the maximum potentional out of the heads, is to get them from someone who knows how to make them work. I would suggest Spreen Racing Engines!

 

 

He currently has a pair of good 441's but was unsure on how much better either the EQ 350i or the 487x flowed in comparison. I know the 487x is getting hard to find but if he can save some $$$ and still have plenty of power with the 441's then he may go that route...

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What we have seen on the flow bench and dyno is that where one may be better at Y flow rate the other is better at X flow rate - but in operation you are accelerating the same through both X and Y. If you can't port polish, radius and gasket match you are better off to get the head that fits your budgets and focus tuning it to give the best performance for your style of driving - then focus on MOMENTUM maintenace (rolling thru the APEX with the most momentum possible. Once you are there and racing door to door at the front, THEN risk trying different out of box heads. (if you are already leading - I doubt you would be asking but rather smugly remaining silent having already found the best combo)

 

Used to be a 454 big block would pass three 350 small blocks in the straight where two of em would get the spots back in the corner while the "boat" would plow through the corner - one car net gain per lap. those days are gone as the suspension knowledge has trickled down and the lighter engined cars carry enough momentum to where all three and even a fourth would get the spot back. I have seen 500 hp cars get beat stupid by junkyard claimer engines because the claimer guy is spending his time and efforts on suspension and tire management. Again I hate to admit this - I am after all an engine enthusiast more than anything else - but at least I am honest in admitting that technology and brain currently has the edge on brute force and brawn...

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I understand where your going with that Mr. Bishop. I have seen many a race won with less power than the other guy on dirt especially. I guess its safe to assume that the open chamber heads like the 441 and 487x when not allowed to do more than just a 3 angle valve job are in essence are very close to once another upon application. With the car setup correctly I just dunno if there is justification in buying a set of the new IMCA legal EQ 350I head when there are is a perfectly good set of 441's or 487x's available. I guess what I mean is are you going to see that much of a difference if prepped the same for the same application...

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I guess what I mean is are you going to see that much of a difference if prepped the same for the same application...

I haven't seen the bench numbers - but looking at them I would assume they are more free flowing at the top end. So you probably wouldn't be gaining a whole heck of a lot on tracks 1/2 mile or less...

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I guess what I mean is are you going to see that much of a difference if prepped the same for the same application...

I haven't seen the bench numbers - but looking at them I would assume they are more free flowing at the top end. So you probably wouldn't be gaining a whole heck of a lot on tracks 1/2 mile or less...

 

He would mainly be racing on 1/4 to 3/8 size tracks around here in S. Texas...

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He would mainly be racing on 1/4 to 3/8 size tracks around here in S. Texas...

3800-5000 RPm responds better to a smaller intake port (rounder cross section) with deeper bowls and an exhaust that is fltter on the bottom radius. the higher velocity of the smaller port keeps the fuel better suspended - and the flat radius of the exhaust cuases a swirl over the radius that scavenges better at lower RPMs. compare a dodge 318 or 360 magnum head to a regular318 or 360 head for a good visual of what I mean.

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