New Dart SHP Block

[Eric68]

Re: New Dart SHP Block

I, too, wish they would ship the blocks at 9.00 rather than 9.025.

That's why they make a 3.800" crank . . . zero deck with a 400 piston at 9.025" GM uses a 3.800" 4130 steel crank in their ZZ383 motors, and I used a Scat 4340 in my 410.

The new 427 is getting custom pistons so I had them move the pin height up .015 "while they were at it" so I don't have the deck the snot out of my Dart block.

9.000 decks would make life easier though . . .

[Robert1320]

Re: New Dart SHP Block

I agree with Eric.

It is silly chop on a 2k block to make it fit an off the shelf piston.
Plus pistons are replaceable and cheaper than the block.

Get pistons to fit customs are not than much more, sometimes cheaper.

[Robert1320]

Re: New Dart SHP Block

Dart "suggests" that you not exceed 600, true. But you know it's gonna happen.

I am sure there is a little room to grow but....

[GibTG]

Re: New Dart SHP Block

So, what is the maximum bore size recommended for this block?

We don't care about this 4.125 in. 'stuff' - that's been done for years.

[Robert1320]

Re: New Dart SHP Block

Dart said

SIAMESED CYLINDER BORES
The SHP block is available with a choice of cylinder bore diameters:
4.00” (PN 31161111) and 4.125” (PN 31161211). Both versions have
siamesed cylinder walls for strength, providing a .230” minimum wall
thickness at 4.165” diameter, the recommended maximum bore size.
The cylinder bores are semi-fi nished to allow the engine builder to
hone for piston clearance and preferred wall fi nish. The stock 9.025”
deck height is compatible with most off-the-shelf pistons.

[GibTG]

Re: New Dart SHP Block

Thanks for the info.

This block doesn't look like anything earth-shattering.

[CTX-SLPR]

Re: New Dart SHP Block

Its not supposed to be, its supposed to be a stock replacement engine with the "best of the breed" stuff. Honestly this is streetrod, street/strip, and cruising machine stuff ment for long term durability at "slightly elevated" power levels. That is why there are Little M blocks out there.

Me personally, if I was given one (I'm not a Chevy guy) I'd probably put a NASCAR surplus short stroke crank in it with the 4.125in bore and put it in a sports car of some sort. Something where the durability of the minorly reinforced block would do well for durability but not so much power as to blow the tires off of it or kill the cornering capabilities.

[Freiburger]

Re: New Dart SHP Block

Its not supposed to be, its supposed to be a stock replacement engine with the "best of the breed" stuff. Honestly this is streetrod, street/strip, and cruising machine stuff ment for long term durability at "slightly elevated" power levels. That is why there are Little M blocks out there.

Correct. In other words, the perfect deal at a lower price for 80% of the marketplace.

[joebogey]

Re: New Dart SHP Block

Dart "suggests" that you not exceed 600, true. But you know it's gonna happen.

So who's going to be the first one to read that as a 600 shot?

[Eric68]

Re: New Dart SHP Block

You know that if guys are making 30 year old GM 400 blocks live at 600-700 HP with .150-.180 wall thickness, you KNOW that this thing will take a bunch more than 600 HP with .250" plus thick walls. Not to mention the other 400 OEM weak points (head bolt and steam holes cracking, 4 bolt main caps and webbing, etc) that have been resolved in this block.

[Freiburger]

Re: New Dart SHP Block

Yeah. Dart says 600 with a wink mostly because they would really like you to go to a Little M for big power. And if you compare the two blocks, it's clear that the Little M is more rigid.

[Robert1320]

Re: New Dart SHP Block

It is all about how much you value you parts.

After spending $3k-$4 on a rotating assy, you toss it into
a $1k or cheaper block.... You get what you pay for.

Street car, street rod, street machine it is a great piece.
A real racecar should have a LittleM.

[Schtauffer]

Re: New Dart SHP Block

Man, you've got cheap local machine shops!

Here's what we pay. I recommend living somewhere other than SoCal.

http://www.jensensenginetech.com/machining.pdf

http://www.jensensenginetech.com/