Have had people call me lying when I tell them I have under 300 rwhp.They dont know how light my car is and there 500plus hp car just got beat by a 62 Valiant with a slnt six.

http://www.wallaceracing.com/Calculators.htm

You can use these calculators to figure out how much power you will need to do what you want. They will get you close.

I used one to get 370 crank HP for my turd on sauce.

Seymour used a pencil and napkin at dinner to get the same answer.

As Sandy and Lou said, dyno numbers are great for playing my pee-pee is bigger than yours, but the only numbers that really matter are the ones on a timecard.

A chassis dyno is a tuning tool. Nothing more, nothing less. There are way too many variables in the way it is set up and run for the numbers to really mean anything. Some guys will set their dyno up real "generous" so they get more business.

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Official Cookie and Mater Tormentor.

The limit is the strength of the block/rotating assemble with the long stroke. Otherwise I don't think the limit has been reached. From a practical street point of view, given tires and traction limits 350 HP is a lot from a slant six on the street. I don't think those with claimed mega power motors can use the power that they claim to have - on the street. The relatively simple ancient 426 hemi design keeps making more power, but the block and metalurgy can handle it. If they had to work with 1964 block technology there's no way that could happen. I doubt if anybody will make a custom slant six block and billet crankshaft. We'll never know the limit. I'm sure 200 HP would seem like a lot to me, but I'll never know

I know this doesn't answer your question,and I hope nobody takes this the wrong way,because I love my slants......but do you particularly want to build a big power slant six powered car or just something different? The reason I ask is by the time you throw big dollars at a slant six you are still limited by the bottom end and head design. Now if you really want a slant then go for it,I would be the last person to say don't do it,look a Cam Tilleys beast,it would be one of the nicest slant powered turbo cars here without doubt and its a beast...but ,if its just something different your after then I'd say build up a 265 Australian Hemi 6, 7 main caps,aftermarket alloy heads and the ability to make some pretty decent power,the factory triple weber E49 street hemi made an advertised 300hp I believe and the race versions were obviously well north of that with the iron head,thats enough to shake up a few smaller displacement V8's. sure it gonna cost money,but so will a serious slant six,just a thought. I have no idea if anyone runs a Hemi over there,but you would certainly be in the minority,and you will make some decent power,even without stretching it to its limit....there are quite a few very quick all engine hemi powered cars over here,most racers tend to go the hemi over the slant for these reasons.

The major drawbacks to a Slant are the small bore which limits valve size, and the small port head. You just can't make a lot of flow. That is why turbocharging works so well, just blow it in.

When built properly block and crank strength are not an issue, and even stock rods are pretty damn tough.

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Official Cookie and Mater Tormentor.

I think a more interesting question is:

" What is the best combination for a N/A max effort slant?"

Calculators are your friend. Slantsix.org is your muse.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

There are only a handful of Aussie Hemi cars here due to the cars not being able to pass our EPA/DEQ restrictions for importation, I know a few more blocks than that were imported as parts (also getting engine parts and rebuild kits kits for these are an import item so that drives the price up a bit, making the cost competitive with rebuilding other hard to get engines... i.e. Nash or Hudson.)

-D.Idiot

I have a 265 inline Chrysler six, the 1952-54 flathead. The 4 3/4-inch stroke is kind of long though, these motors have good low end torque. I don't see them too much as these were the budget big Chrysler motor a year after the 331 hemi became available. With an overbore 283 inches is common. These were also used in heavy duty trucks, some trucks might have come with two carbs. I think the Australian inline six was originally intended to replace this series of sixes for trucks, but the small block V8 was deemed more cost effective. In the late 1940s a prototype 331 hemi head was developed on the 251 version of this six but there was no serious attempt to make a production version as a cross flow inline head didn't have easy carb heat, and sixes were increasingly being accepted as the economy motor in the US. A few toyed with releasing a hemi head casting for the old sixes but nothing ever came from it. At 3.438 inch the bore of the 265 L-head is similar to a slant six, whereas the 331 allowed larger valves, but a hemi inline six that had the same valve geometry as the 241 Dodge hemi would have been an cool oddball. There was also a faction within Chrysler that wanted to keep building the flathead six forever for the numerous economy buyers, but conceded that for competitive reasons a OHV motor was necessary - the old motor was just too heavy for the new Valiant. The slant six was canted to allow for a lower hood line, but the L-head is lower yet. The last of the 230 L-heads were capable of similar baseline specs ( on paper ) as a 225 as long as the 225 retained its minimal compression ratio which it did throughout the years - but the two carb versions of the 230 cost too much money to build. Sales of basic L-head inline six models remained strong until the end as the old L-head was considered to be indestructible and easy to maintain, and therefore the 225 never really strived to be a performance motor to meet the same market conditions.

I think Mike Jefferies COMBO,that I followed and built is a pretty good one.HIS head and guideness is what has gotten me my records.Seymores advise,ideas and beeing a mentor also got me a quick six.Without these two I probably wouldnt have any records.Mark

I want to build a big power slant and mostly a clone of the Dragmaster Dart Six rail because I have found the actual Hilborn injection unit that came off it in the 60's. I would also like to build a "clone" that goes alot faster than 130mph and only in the 10's.

As for something "different" my wife's 48 chevy aerosedan with a narrowed 56 caddy front bumper, narrowed 60 Impala dash, hydraulics, 100 spoke Daytons, slant six and Lynx intake with 3 weber carbs takes care of the "different" category.

There are a few guys that import the Assie sixes into the US but I'm not really into them. Besides, I already have a garage full of slants and slant goodies so it is too late to reform me.

Sounds like some great projects, JR. Look forward to meeting you someday.

Lou

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Home of Slant6-powered fun machines since 1988

OK, so I have a Cadillac CTS, 3.6L direct injection, and it puts out 310 HP. It's a six speed manual and fun to drive, but way heavier than my '67 dart.

I would be absolutely thrilled to get 300 HP out of my 3.7L N/A slant. I read the previous entries and laughed outloud when I heard 650 hp out of a slant, not that I don't believe it, more like I was enjoying the wonders that are the slant six...especially when they eat V8's for breakfast.

Right now I have dual 2bbl Weber 32/34 DFT carbs on my slant with a street cam, very tame but respectible power and performance. It was an experiment, and I'm happy with it as my daily driver....but someday...

What does it take to get to 300 HP? I don't want to change my current engine, it's my daily driver...but I'm thinking of down the road, say in 5 years or so, after all my other work is done and I have a completely redone Dart....having a 300 hp slant already built and ready to drop in as a replacement would be awesome. How much investment, assuming I have someone build the long block for me, dial in the cam, are we talking about? Does anyone build slants of this flavor?

thanks all,

bg

I believe the price would be similar to a high end MP crate engine, but so far the Jeffries Prepped engines in other cars I've raced against are reliable,
money winners, and some are in that power class... not sure they'd work so great on the street, but on the track you can hear impending doom getting ready to pass you a few seconds after you've left the tree...



-D.Idiot

300 horse on a Slant takes a really good head, a really good camshaft, and a lot of compression.


Or a bottle, turbo, or blower.

Remember, this motor was a low tech economy motor that was designed over 50 years ago. Comparing it to anything built today will lead to extended bouts of depression.

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Official Cookie and Mater Tormentor.

250 hp would be OK, if 300 is harder or the engine might wear more quickly...

I know I can't compare to modern stuff, my buddie has a four cylinder Mazda pushing excess of 300hp..

Just testing the waters...fun stuff.

BG