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Bass Lake Dream'n
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Discussion Starter #1
I have a tunnel ram and carbs I want to use boat am short of cash for new heads right now. The heads are iron 049's on a 468bbc, 9:1 comp w/ a solid lift cam (i'll dig up the specs later if needed).
What if any problems can arise if I make this swap? I have read on other hot rod forums that this is not a problem, guys even said they saw better et's. That's cars, what about a v-drive?
Thanks.
 

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Im running rect port t ram on oval port heads and see no problems. It turns 5k with a single 650:))eek:)) in my v-drive with 15% gears. If you want you can port match the heads to the t ram ports and get better flow.
 

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I would think you would be better off if the heads were rec. and the manifold oval, I can see that working much better. Picture this, you are driving at 65 mph on a four lane highway, which suddenly with out warning necks down to three lanes. The flow and direction will be severly inhibited at the transition point. Oval port TR's are available cheaply on e bay or racingjunk.com all the time, I would be looking for the proper fitment.
 

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I'm famous !
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Its doable for short term . I have read about "puddling" problems" ( fuel )
 

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just make sure u use the rite gaskets! :)

FWIW...u can NOT use a oval port manif on rect port heads!!! :)...it will not work, period

FastRat
 

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just a ski boat with bark
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just make sure u use the rite gaskets! :)

FWIW...u can NOT use a oval port manif on rect port heads!!! :)...it will not work, period

FastRat
It depends on the intake as long as it has enough flange to use the rectangle port gaskets it will bolt up and seal. No promises on performance but after owning both I know the Weiand Team G oval port will bolt up and seal to a set of rectangle port heads.
 

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I would think you would be better off if the heads were rec. and the manifold oval, I can see that working much better. Picture this, you are driving at 65 mph on a four lane highway, which suddenly with out warning necks down to three lanes. The flow and direction will be severly inhibited at the transition point. Oval port TR's are available cheaply on e bay or racingjunk.com all the time, I would be looking for the proper fitment.
You are killing your flow. Small oval port 049 heads when massaged with a manifold that matches will surprise many people with the flow numbers. Might not make major cfm #'s but the velocity #'s will help put more charge in the chamber. A larger intake helps too. My son has gone as large as a 2.300 intake in the 049 head. But no mater what you do it all comes down to your total combination and what rpm range you expect to run. Bottom end to mid range dual plain manifolds for up to 6000 rpm. 6000 and up single plain manifolds . Tunnel rams look cool but are for rpm application up to the moon and beyond . The secret to making anything work good is the proper combination. But a tunnel ram with oval port runners on a 049 head will surprise the hell out of you:(:(
 

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Bass Lake Dream'n
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Discussion Starter #8
right now I'm running a single plane Dart with a 800cfm holley. turns 6500rpm w/ 15% gears. An honest 80-85mph on gps. I have 2 750's that will sit on top the t/r.
What work should/could i do to the valves on these old 049's?
 

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just a ski boat with bark
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right now I'm running a single plane Dart with a 800cfm holley. turns 6500rpm w/ 15% gears. An honest 80-85mph on gps. I have 2 750's that will sit on top the t/r.
What work should/could i do to the valves on these old 049's?

If mph is what your after you maybe be disappointed, not sure if my results are typical but when I switched from a Weiand Team G with a flowed 850 (990cfm) to an Edelbrock Victor 2R with dual 750s I only gained 1-2mph but th boat was quicker. Personally I expected more mph and not much on ET.
 

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E-7 Sheepdog (ret)
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right now I'm running a single plane Dart with a 800cfm holley. turns 6500rpm w/ 15% gears. An honest 80-85mph on gps. I have 2 750's that will sit on top the t/r.
What work should/could i do to the valves on these old 049's?
Have the factory large size valves installed, and some mild porting work, bowl cleanup, redius blending (espcially the short side), a bit of relieving on the chamber side close to the side of the new bigger intakes.

The above work, plus reduced valve stem size to 11/32 (then the undercut Manley Pro Flow valves also) made a huge difernce on my fairly modestly modded 454, single carb on a Perf. RPM Air Gap.
The head work alone picked me up 400RPM against an Aggressor B in a tight pump, and even better throttle response than it had before..
 

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Bass Lake Dream'n
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Discussion Starter #11
If mph is what your after you maybe be disappointed, not sure if my results are typical but when I switched from a Weiand Team G with a flowed 850 (990cfm) to an Edelbrock Victor 2R with dual 750s I only gained 1-2mph but th boat was quicker. Personally I expected more mph and not much on ET.
I'm more interested in the "quickness", not too concerned with top end.

Also like the look:)devil
 

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steelcomp was here
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The mismatch issues for the most part are a misnomer. Air will pack against the face if the head where the mismatch is and creat a boundry layer, while the sharp edges of the port will "shear" the air that's entering the port. The transition is actually relatively smooth. It's not an ideal scenario, but just blending the opening of the port to match the intake will gain very little, if anything and if done poorly will cause more turbulence than if left alone.
The 049's are a great cantidate for larger valves, a good quality valve job and a bowl blend. On anything under 500" you can make excellent power up to about 6500rpm.
 

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steelcomp was here
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No matter what, make no attempt to do this. This is just a waste of time and does absolutely nothing. Could possibly even hurt the flow. Steelcomp, do you remember seeing these in a post a while back on this same subject.
Yes, this is precisely what I'm talking about.
Bad ju ju.
 

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It will work just fine. Make sure you use a rect port gasket. I have been running mine like that for a long time. You will have no problems!
 

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Bass Lake Dream'n
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Discussion Starter #16
You guy's are the greatest! I don't care what "they" say about you;)
What size valves should i be looking for?
Thanks for the help.
 

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No matter what, make no attempt to do this. This is just a waste of time and does absolutely nothing. Could possibly even hurt the flow. Steelcomp, do you remember seeing these in a post a while back on this same subject.
I have a set of junk Ford D3 heads gasket matched to CJ ports that look like that, the porter/hacker went a whole 3/8" into the port to blend it in :|err

The Ford Marine Engine used a CJ manifold on stock heads, which bumps the power up like 25hp when compared to the stock small port intake.
 

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steelcomp was here
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You guy's are the greatest! I don't care what "they" say about you;)
What size valves should i be looking for?
Thanks for the help.
Unless you're going for a full port job, a 2.19 intake, 1.88 ex is what will work. I do this conversion all the time. Like Smokin said, go with the 11/32 stem and it helps even more. Too bad you're not closer...I'd be glad to help you out on these if youd decide to got that way.
 

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No matter what, make no attempt to do this. This is just a waste of time and does absolutely nothing. Could possibly even hurt the flow. Steelcomp, do you remember seeing these in a post a while back on this same subject.
Wow this happens alot, I recently thrashed a set of 290 castings due to this. I knew the engine had mismatched heads and intake but never thought anyone would destroy a port entry to try and match them up. When we tore it down I was shocked. I wish I had a photo they where much worse than that, We now call that the squorval port. If you wan't to mismatch heads, or intakes thats fine it will work I see it all the time, but don't hack up you'r stuff doin it.

P.S. I don't do this or recomend it. SJ
 
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