stock heads or ported? You could pick up some easy cfm if you back cut the valves while apart.
My BUDGET 451 build... finally
- Thread starter HT413
- Start date
HT413
Semi Pro Bowler
That's a great idea, 69, thanks. I'm going to run them stock/unported. Im going to have a conversation with the machinist when he pulls them apart and I'll definitely ask him his thoughts on back cutting the valves and maybe some other simple things he could do to kick it up a notch.
I'm sure you're going to port match also?
HT413
Semi Pro Bowler
Ya know, I was just going to come on here and ask you guys what other little tricks I could do to maximize things (on a budget of course lol). Yep, I plan on port matching the intake and heads and I've been considering trying my hand at blending the bowls myself but honestly, I'm probably going to leave that for a future project if i decide I want to kick it up a knotch in the future.
Any other ideas?
Port match exhaust side also, smooth out any casting bumps. Flapper wheels work great for that.
Is it ok to match exhaust port to exhaust IQ52? Have I been doing it wrong all these years? Thanks for the info.
HT413
Semi Pro Bowler
GOT SOME GREAT NEWS from the machine shop. Everything looked great. He looked at the heads, valves and seats and from what he saw, the valve job that was done looks great. The seat width on the valves are good and not too high or too low on the valve underside surface while the seats in the heads showed the same thing. My buddy is going through the springs and checking the guides - no word on that yet, as first I need to get a hold of lunati for a spring recommendation.
Honestly, from what I've read about aftermarket heads, I had budgeted a few hundred $$ for repairs, so it's like found money!
Honestly, from what I've read about aftermarket heads, I had budgeted a few hundred $$ for repairs, so it's like found money!
IQ52
Well-Known Member
Unless you have a flowbench and have observed the differences of opening various sides of the port exit, it is best to leave the exit stock. It's too easy to lose flow by getting too big. Opening to the tubing header size is completely unnecessary. Some lip seems to help prevent reversion into the head. A particularly bad place to open the exhaust exit is the bottom or floor.
lewtot184
Well-Known Member
X2!
Thanks for the enlightenment!!!!!!!!!!!
Garys1969RR
Well-Known Member
Good to see you are getting near the completion of this build. My 451 will be entering its 4th season of drag racing this summer. 3rd season with the ported 915 heads. Still pulling consistent mid 12s @ 110MPH. Great motors! On parts cleaning, I bought a used parts cleaner for 50 bucks from a buddy and it works great! I buy my parts cleaning solvent from Hill Petroleum distribution company. They pump it from a 55 gallon drum, so the price is right. Let us know how that thing runs, can't wait!
HT413
Semi Pro Bowler
Alright well the hits keep on a comin! After talking with my buddy and lunati, the 440source springs will work fine with the cam! They want 125 on the seat and 300-325 open pressure and those source springs are measuring just right. Plenty of room to avoid coil bind on the 513/533 lift this cam has. Saves me another $200.
So I have to give a shout out to the 440source guys. For all the 'chinese junk' comments you read, their machine work and components are first rate out of the box (for me anyway).
So I have to give a shout out to the 440source guys. For all the 'chinese junk' comments you read, their machine work and components are first rate out of the box (for me anyway).
HT413
Semi Pro Bowler
Well with my garage / addition taking forEVER, looks like the 451 won't be installed for a few months, since I have no room to work. :eusa_doh:
Sooooo, I decided to put the 440source balancer on the 413 just for giggles and guess what I found.... the OEM truck balancer is off by 20 degrees. Instead of the TDC mark being 90 degrees from the keyway, it's only 70. Does that mean my timing was 20* more advanced or retarded than I thought? :icon_rolleyes:
Sooooo, I decided to put the 440source balancer on the 413 just for giggles and guess what I found.... the OEM truck balancer is off by 20 degrees. Instead of the TDC mark being 90 degrees from the keyway, it's only 70. Does that mean my timing was 20* more advanced or retarded than I thought? :icon_rolleyes:
GrabberOrange69
Well-Known Member
Are you sure the 440source balancer isn't the one that's "off"?
HT413
Semi Pro Bowler
Good question. I've read that the TDC mark should be 90* from the keyway, which the 440source damper is. so I *guess* it's correct?
747mopar
Well-Known Member
Do you have a piston stop? I always degree my cams and double check the balancer while I'm at it just to be sure. Looking forward to seeing this thing run.
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Nice to see this confirmed. I read the same thing while porting mine and it makes sense seeing how if you get the exhaust port a little bigger you'd create a lip to disrupt the flow. Good info
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Nice to see this confirmed. I read the same thing while porting mine and it makes sense seeing how if you get the exhaust port a little bigger you'd create a lip to disrupt the flow. Good info
Garys1969RR
Well-Known Member
In my understanding of the reversion effect, you want the ex port a little smaller than the header port opening. That way, when positive pressure pulses travel back to the ex port (which we don't want) they encounter a small reflective surface (the "lip") which reflects them back down the header pipe. Hopefully. This is a simple way of describing a complex situation, but it seems to help. Otherwise with out the lip, the positive pressure is going to move to the ex valve and force ex gas back into the ex port.
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The same effect can be had on the intake manifold side, by having the manifold port slightly smaller than the head port. I like to do this especially on the floor of the port, as I think the reversion pulses tend to travel along the floor.
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The same effect can be had on the intake manifold side, by having the manifold port slightly smaller than the head port. I like to do this especially on the floor of the port, as I think the reversion pulses tend to travel along the floor.
HT413
Semi Pro Bowler
Hey there guys, been a while since I've updated, mostly because I've been working like a dog on my home addition. Well, at the suggestion of many of you, I called Frank Lupo at Dynamic and ordered my converter. The motor will be built this winter but I figured I had a little cash, might as well get it ordered now. Pretty stoked!
I should add that I had to resist a STRONG urge to pickup a used converter to 'save some cash', but was able to STAY STRONG and get one spec'd out for me by an expert.
I should add that I had to resist a STRONG urge to pickup a used converter to 'save some cash', but was able to STAY STRONG and get one spec'd out for me by an expert.
747mopar
Well-Known Member
5,000 + miles on mine now....... nothing but pure pleasure haha. I was hoping that when I saw this thread updated it meant you had it done!!!!! Oh well, winter is almost here now. Good luck
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