I bought a Dick Landy 144 roots blower setup off a member Jimjimmy that I plan on putting on my 64 Barracuda. It has a basically stock 2bl 273 w/ a .450 hydraulic summit grind cam. A buddy has some j-heads redone w/ 1.88valves with a good valve job. Will these bolt right up? Would I have to notch the cylinder walls? Thinking on the fly here... Would it be worth it?
273 Question.
- Thread starter Scampin
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67Dart273
Well-Known Member
You don't want the "big" heads without high compression pistons, or the compression will be VERY low. I don't know for certain on valve clearance
Blower sounds interesting. I've been thinking of one of the Eatons that are on stuff like Jags and Fords
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Well firstly, what heads is the intake under that blower designed to bolt up to? cuz the 64s were the old style intake with the odd bolt angle. So if the 144 bolts is set up for the later intakes, then you might be able to kill two birds with one stone.
Next, like Del says, the open-chamber heads might not be the best solution. They could add 10 cc to the total chamber volume. With 2bbl pistons in there, your CR would drop pretty low, which might not be the end of the world, once moving. But when trying to get off the line, it might be soft. A loose TC might get you going, allowing the blower to put out a few psi's. Or a little more gear out back. But I'd try it with the stock stuff first, and take it from there.
I think some math might be in order, and then maybe a little millwork.
Actually the CR might not be so bad. A quick bit of math says the J-heads might drop it to 7.2ish. Your results may vary.
I did the math on fitting those valves into a 3.625 bore, and I just can't see it fitting, even with notches. Maybe someone else will come along that knows for sure.
Next, like Del says, the open-chamber heads might not be the best solution. They could add 10 cc to the total chamber volume. With 2bbl pistons in there, your CR would drop pretty low, which might not be the end of the world, once moving. But when trying to get off the line, it might be soft. A loose TC might get you going, allowing the blower to put out a few psi's. Or a little more gear out back. But I'd try it with the stock stuff first, and take it from there.
I think some math might be in order, and then maybe a little millwork.
Actually the CR might not be so bad. A quick bit of math says the J-heads might drop it to 7.2ish. Your results may vary.
I did the math on fitting those valves into a 3.625 bore, and I just can't see it fitting, even with notches. Maybe someone else will come along that knows for sure.
I like the bigger chamber 360 heads on the little blower motor. IMO, that's what you want for a street driven blower motor. Very low static compression and let the blower do the work.
What he said^^^,nice score on the blower. (Always wanted one)
Yeah the motor has the original heads with the odd intake angle. I was thinking it would be kinda criminal to modify the intake since there are so few of them out there. Based on the loose calculations of the blower pulley size (blower is still in transit so I dont have definitive numbers yet) it was something like 16psi output using an online calculator and fuzzy math. So maybe if it is anywhere near that, dropping the compression down alittle more probably isn't the worse idea. The car is a 4spd w/ a spec ceramic clutch and 3.23 posi.
nm9stheham
Well-Known Member
Exactly right on the lower CR and open heads. The last thing you want with any pressurized system is too much compression; with boosts in the 15 psi range, the compression pressures jump well above 200 psi even with low SCR's. The open heads are the right pace to start, and you may even want/need some dish top pistons. I don't know how much pressure this blower makes; I assume it can be geared/belted up or down to get the desired pressure. (Oh yeah, I see you are looking at that.) But that will play into the CR desired.
Just shooting from the hip with one data point..... We use a true 8.2:1 SCR on a turbo Starion 2.6L engine with 14-15 max turbo boost, and that is pushing above the stock factory CR levels which were an abysmal 7.3:1, but were all-around safe for up that level of boost. Our engine gets hammered as a rally car engine, so it has to be a bit on the conservative side. 8.2:1 may be on the edge of too much for a blower setup, since you can get lots of pressure down at low RPM's.
And if the valve-to-block clearance is a problem, I would consider using open 318 heads. The blower will make up for the smaller runners and valves at low and mid RPM's and even to some extent at higher RPM's. A thinner rather than thicker head gasket should also be a consideration. Might be a good place for a Cometic, though our Starion does just fine with a stock Felpro composite.
Sounds like a lot of fun!
Just shooting from the hip with one data point..... We use a true 8.2:1 SCR on a turbo Starion 2.6L engine with 14-15 max turbo boost, and that is pushing above the stock factory CR levels which were an abysmal 7.3:1, but were all-around safe for up that level of boost. Our engine gets hammered as a rally car engine, so it has to be a bit on the conservative side. 8.2:1 may be on the edge of too much for a blower setup, since you can get lots of pressure down at low RPM's.
And if the valve-to-block clearance is a problem, I would consider using open 318 heads. The blower will make up for the smaller runners and valves at low and mid RPM's and even to some extent at higher RPM's. A thinner rather than thicker head gasket should also be a consideration. Might be a good place for a Cometic, though our Starion does just fine with a stock Felpro composite.
Sounds like a lot of fun!
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