Does it rev less / like to rev less with a 198 crank vs the 170 crank?

Greg

_________________
http://www.youtube.com/hyperpack

Well, more power per cylinder for 198 crank might give higher revving, but shorter stroke for 170 crank and larger head flow per cylinder might favor higher revving. Also, the shorter the stroke, the less load on rods, pistons, and bearings at a given RPM. I see no reason you could not rev 7000 with either crank given that a 225 will rev 6000 reliably. Valvetrain might be another issue...

Lou

_________________
Home of Slant6-powered fun machines

The question is even if the 210 will turn 7000 rpm will the head support that amount of air?

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Less cubes ....does it require less runner cfm?

I thinks we will find out.

I bet if you get a skookum 1.75- 1.8/ 1.50 valve head with good work done to it, it could.

_________________
http://www.youtube.com/hyperpack

Yes, fewer cubes will require less head CFM at a given RPM.

Lou

_________________
Home of Slant6-powered fun machines

And if you need more oxygen, there is always this, "N2O". The 170 engine that was in my Cuda went 7,000 rpm a few times. But I would suggest using a low mount DS alternator. That long belt with a pass side alt, doesn't like staying on at that rpm.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 225 nitrous
64 Valiant Signet
64 Valiant 4dr 170

The 225 in my car goes 7000 in the water regularly. I used to shift on track at 7000, but it makes no power over 6300.

_________________
Official Cookie and Mater Tormentor.

That is a Jeffery built engine and Head correct?

It's probably the exception rather than the rule.

_________________
http://www.youtube.com/hyperpack

Mike gives me hell every time I tell him that.

Personally I try to stay away from even less cubes than a 225. When you're already handicapping yourself with a small motor why make it worse with less power band?

_________________
Official Cookie and Mater Tormentor.

I bet that narrow power band is fun on the street when built properly.

For all out drag racing.... then booost or bottles may be needed.

it's all relative.



Greg

_________________
http://www.youtube.com/hyperpack

I built a couple of "low block" 210 Slants mostly just to see if it could be done and how they worked...
And they "work" like a bored-out 198, less a little weight.

As already noted, no big power gain or magic out of this combo but if I were to stick a SL6 into a little sports car, with a low hood line, I would likely use a low block 210.

Truth is, many of the experimental hybrid SL6 engines I built over the years were done to satisfy my curiosity and "because I can" attitude... instead of trying to make the most horsepower out of an SL6.
DD