3 cyl, 2 valve, scratch build

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agertz1
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3 cyl, 2 valve, scratch build

Post by agertz1 »

Easy part is Buick Stg II V6 aluminum head fully ported. 2.15" Int., 1.56" ehx., Ti valves and Pankl rods. 4" coated bore, 3.2" stoke = 2L. Some webb
has flow #'s for this head, so I can extrapolate hp. ? ? Would like max hp. around 8,500. Electronic inj. with E85.
Suggestions ? Thanks, Art.
PackardV8
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Re: 3 cyl, 2 valve, scratch build

Post by PackardV8 »

Intended use?

IIRC, some at Bonneville running alcohol use billet blocks with no coolant.
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agertz1
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Re: 3 cyl, 2 valve, scratch build

Post by agertz1 »

Welded, 6061 T6. Very light recip. and crank. I suspect E85 won't cool like all that volume of methanol ? 90% street use. Small rad. and fan.
Would like to see about 200 hp. ?
Thanks, Art.
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Re: 3 cyl, 2 valve, scratch build

Post by agertz1 »

Other part of cam design, with a 1.82/1 finger roller rocker ratio,( high loading on lobes), base circle should be approx. ?
PackardV8
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Re: 3 cyl, 2 valve, scratch build

Post by PackardV8 »

agertz1 wrote: Fri Jul 09, 2021 2:10 pm I suspect E85 won't cool like all that volume of methanol ? Thanks, Art.
Art, suspect but verify.

Ethanol contains about 84,600 BTUs/gallon, which is about 27% less than gasoline, but about 30% more than methanol. Consequently, a race engine converted from methanol to ethanol typically uses less fuel (30 to 40% less) to make the same level of power. As an added benefit, the engine runs cooler and reduces the risk of overheating.
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dannobee
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Re: 3 cyl, 2 valve, scratch build

Post by dannobee »

If you want rules of thumb, 0.257 x cfm x #cyls= potential hp.
Want another one? Max effort race engine will make 1.6 lb ft torque/cu in. Very hot street engine will make 1.4 lb ft torque/cu in.

If your engine is 120 cu in and the head flows 300 cfm, potential hp is about 230hp with peak torque of 190 lb ft if a max effort unrestricted race engine. If you add various rules, adjust downward as necessary.
agertz1
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Re: 3 cyl, 2 valve, scratch build

Post by agertz1 »

For sake of simplicity and since dedicated E85 fuel, I think coated aluminum barrels,( air cooled) will do.
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Re: 3 cyl, 2 valve, scratch build

Post by agertz1 »

Thinking ahead,
I will need a cost-effective, electronic inj. system. If oem. anything tunable, while adding E85 compatible injectors suited for 2L. ?
Thanks, Art.
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Re: 3 cyl, 2 valve, scratch build

Post by Racer71 »

AEM ems4 might be a fair efi ecu for you. I have used a few and they’re not bad for a good price point. Pretty flexible as well.
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Re: 3 cyl, 2 valve, scratch build

Post by agertz1 »

AEM.... is this aftermarket ? Where might I find ? Art.
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Re: 3 cyl, 2 valve, scratch build

Post by agertz1 »

Using the Ford 4.6L 2V, finger roller cam followers and hyd. lash adjusters. Will this limit rpm., ( pump up), like a push rod application ? Plunger range is ?
Rocker ratio is ? Why is the cam base circle so huge ? Do cam lobes thrust towards lash adjusters ?
Thanks, Art.
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