Parts

Parts Bin: New Summit Racing-Dart Short Block Kits for GM Engines

Dart, with their ever evolving line of affordable SHP blocks; has added features once only found in high-end racing blocks. With new offerings for traditional small block, LS, and big block Chevy; Dart and Summit Racing put together some great new short block kits.

The first and most notable aspect of these combinations is they are BIG! If you are going with a new block, you might as well start with Siamese bore sizes and never look back. The blocks are bored within .010 of finish hone, which allows you to fit to the pistons and exact application.

The small block and LS applications start at 4.125 in. bore and the big blocks comes in at 4.600 in.

Within these bores, there’s a large variety of crank/rod/piston components to hit about any compression target you’re looking for. Whether it’s naturally aspirated, forced induction, or nitrous; a combination can be built.

The blocks are stroker clearanced, so why not put some arm in them at the same time?

The traditional SBC gets a 3.750 in. stroke to avoid the need for small base circle cams. The LS combinations are built around both 3.622 in. or 4.000 in. strokes. The big block gets a 4.250 in. stroke crank. These are common components, so they’ll drop in with little fuss or added machine work.

The small block hit 400 c.i.d. The LS combinations are available in 387 and 427 c.i.d. The standard deck height big block hits 565 c.i.d. Because everything is brand new, you can always bore it even bigger later.

Here are some of the cool features found in each of the Dart blocks:

SBC – SHP Block

The block used as the basis for these combinations is part number DRT-31161211.

It has the priority main oiling, extra-thick cylinder walls, main webbing, and improved water jacketing. It has a proven splayed 4-bolt main cap arrangement. It also has provisions for OE hydraulic roller cams.

LS – SHP LS Next

The foundation for these combinations is part number DRT-31867211.

Yes, it’s tough. It also has the priority main oiling, extra-thick cylinder walls, main webbing, and has improved water jacketing.

Improvements were made over the factory design. It gets a proven splayed 4-bolt main cap arrangement for reduced windage and to strengthen the main webs. The cylinder lengths are further extended to better support the piston at bottom dead center (BTC) when used with longer strokes. Finally, it has the provision for 6-bolt per cylinder heads for better head gasket seal under extreme boost.

BBC – Big M Sportsman

These combinations get the DRT-31273644 Dart Big M Sportsman block.

It has a standard 9.800 deck height and a cylinder wall thickness of .300 even at its 4.600 bore. Like the others, it uses a splayed 4-bolt main arrangement with priority main oiling. It receives provisions for a sixth head stud in the valley for better head gasket seal. Installation is simplified with all the standard bosses and mounts built in.

How about the rotating assemblies?

Durability and affordability are factors here, so it was decided that each of the combinations would receive K1 4340 forged cranks and stout H-beam rods with ARP 2000 bolts. These have an excellent reputation for tolerance and finish.

What about the pistons?

Forged is the way to go, and the Summit-Dart team decided to aim for compression ranges in the 9.5 to 10.5:1 with the ability to mill heads for extra compression getting up into the 11.5:1 range.

There is a single exception because sometimes people need a big-compression monster big block. Dart and Summit Racing were happy to oblige. The top of the lineup is a 14:1 565 c.i.d. brute!

Below are easy-to read tables with all of the specs for the components and the compression-ratio combo available with common combustion-chamber volumes. Note that all compression ratios are figured at .045 piston-to-head clearance.

First, we’ll start with the traditional small block Chevy combinations. There are two basic piston part numbers depending on the combustion chamber size and target compression ratio.

Here are the lower compression versions:

SBC 400 c.i.d. kit P/N
Crank Forged 3.750 in. Stroke
Rod Forged H-Beam 6.000 in.
Forged Pistons 4.125 Bore
0 deck atC.R. @ 72ccPinRings
9.8:1 compression @ 72cc, CLE-CB663HN rod, and CLE-MS909H main bearings
CMB-08-0086
KOT-012DAD375
KOT-012AD25600
WIS-PTS546AS
11cc Rev. Dome


9.000
9.8
Full Floating 0.927
1/16, 1/16, 3/16
SBC 400 c.i.d. kit P/N Crank Forged 3.750 in. StrokeRod Forged H-Beam 6.000 in.Forged Pistons 4.125 Bore 0 deck atC.R. @ 67ccPinRings
10.4:1 compression with 67cc chamber, CLE-CB663HN rod, and CLE-MS909H main bearings
CMB-08-0087KOT-012DAD375 KOT-012AD25600 WIS-PTS546AS
11cc Rev. Dome
9.00010.4Full Floating 0.9271/16, 1/16, 3/16

Here are the higher compression versions:

SBC 400 c.i.d. kit P/N
Crank Forged 3.750 in. Stroke
Rod Forged H-Beam 6.000 in.
Forged Pistons 4.125 Bore
0 deck atC.R. @ 72ccPinRings
10.5:1 Compression Ratio @ 72cc, CLE-CB663HN rod, and CLE-MS909H main bearings
CMB-08-0088
KOT-012DAD375
KOT-012AD25600
WIS-PTS525AS 5cc Flat Top

9.000
10.5
Full Floating 0.927
1/16, 1/16, 3/16
SBC 400 c.i.d. kit P/N Crank Forged 3.750 in. StrokeRod Forged H-Beam 6.000 in.Forged Pistons 4.125 Bore 0 deck atC.R. @ 67ccPinRings
10.9:1 Compression Ratio with 67cc chamber, CLE-CB663HN rod, and CLE-MS909H main bearings
CMB-08-0089KOT-012DAD375 KOT-012AD25600 WIS-PTS525AS 5cc Flat Top9.00010.9Full Floating 0.9271/16, 1/16, 3/16

Next, we have the LS combinations with 24X and 58X reluctor cranks with pistons that achieve target compression ratios.

First is the 387 c.i.d. high- and low-compression versions for 24X reluctor cranks:

LS 387 c.i.d. 24X Reluctor kit P/N
Crank Forged 3.622 in. Stroke
Rod Forged H-Beam 6.125 in.
Forged Pistons 4.125 Bore
0 deck atC.R. @ 65ccC.R. @ 70ccPinRings
8.8:1 with 70cc chamber, 9.4 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0078
KOT-012FAE36224

KOT-012AE25613
JEP-312034-8 21.8cc Dish


9.240

9.4

8.8
Full Floating 0.927
WIS-4127GFX 1.2, 1.2, 3.0mm

10.8:1 with 70cc chamber, 11.5:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0080KOT-012FAE36224 KOT-012AE25613WIS-K0005X125 1cc net Dish
9.23611.510.8Full Floating 0.927WIS-4127GFX 1.2, 1.2, 3.0mm

Here’s the same thing except with 58X reluctor cranks:

LS 387 c.i.d. 58X Reluctor kit P/N
Crank Forged 3.622 in. Stroke
Rod Forged H-Beam 6.125 in.
Forged Pistons 4.125 Bore
0 deck atC.R. @ 65ccC.R. @ 70ccPinRings
8.8:1 with 70cc chamber, 9.2:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0079
KOT-012FAE36258


KOT-012AE25613
JEP-312034-8 21.8 cc Dish


9.240

9.2

8.8
Full Floating 0.927
WIS-4127GFX 1.2, 1.2, 3.0mm

10.8:1 with 70cc chamber, 11.5:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0081KOT-012FAE36258
KOT-012AE25613WIS-K0005X125 1cc net Dish
9.23611.510.8Full Floating 0.927WIS-4127GFX 1.2, 1.2, 3.0mm

Next up, let’s look at the 427 c.i.d. versions. Here are the 24X reluctor ring version in high- and low- compression:

LS 427 c.i.d. 24X Reluctor kit P/N
Crank Forged 4.000 in. Stroke
Rod Forged H-Beam 6.125 in.
Forged Pistons 4.125 Bore
0 deck atC.R. @ 65ccC.R. @ 70ccPinRings
9.8:1 with 70cc chamber, 10.2:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0082
KOT-012FAE36224

KOT-012AE25613
WIS-K452X125 20cc Dish

9.235

10.2

9.8
Full Floating 0.927
WIS-4127GFX 1.2, 1.2, 3.0mm

11.0:1 with 70cc chamber, 11.5:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0084KOT-012FAE36224 KOT-012AE25613WIS-K395X125 8cc Dish

9.23511.511Full Floating 0.927WIS-4127GFX 1.2, 1.2, 3.0mm

And finally, the 427 c.i.d with 58X reluctor cranks:

LS 427 c.i.d. 58X Reluctor kit P/N
Crank Forged 4.000 in. Stroke
Rod Forged H-Beam 6.125 in.
Forged Pistons 4.125 Bore
0 deck atC.R. @ 65ccC.R. @ 70ccPinRings
9.8:1 with 70cc chamber, 10.2:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0083
KOT-012FAE36258


KOT-012AE25613
WIS-K452X125 20cc Dish

9.235

10.2

9.8
Full Floating 0.927
WIS-4127GFX 1.2, 1.2, 3.0mm

11:1 with 70cc chamber, 11.5:1 with 65cc chamber, CLE-CB663HN rod, and DRT-9MS2321H main bearings
CMB-08-0085KOT-012FAE36258
KOT-012AE25613WIS-K395X125 8cc Dish

9.23511.511Full Floating 0.927WIS-4127GFX 1.2, 1.2, 3.0mm

What’s better than 427 cubic inches? 565 cubic inches! With the big block Chevy, there are three basic compression ratios available, all easily adjusted with milling and head gaskets thickness.

BBC 565 c.i.d. 9:1 kit P/N
Crank Forged 4.250 in. Stroke
Rod Forged H-Beam 6.385 in.
Forged Pistons 4.600 Bore
0 deck atC.R. @ 114ccC.R. @ 119ccPinRings
8.7:1 compression with 119cc, 9:1 with 114cc chamber, CLE-CB743HN rod, and DRT-9MS829H main bearings
CMB-08-0095
KOT-012GAG425

KOT-012AG33639

WIS-K0135A100 19cc Dish

9.780

9
8.7Full Floating 0.990
WIS-J820SB4600-5 1/16 1/16 3/16

BBC 565 c.i.d. 10.9:1 kit P/N Crank Forged 4.250 in. StrokeRod Forged H-Beam 6.385 in.Forged Pistons 4.600 Bore 0 deck atC.R. @ 114ccC.R. @ 119ccPinRings
10.9:1 compression with 119cc, 11.4 with 114cc chamber, CLE-CB743HN rod, and DRT-9MS829H main bearings
CMB-08-0096KOT-012GAG425
KOT-012AG33639
WIS-K0245A100 15cc Solid Dome
9.780
11.410.9Full Floating 0.990WIS-J820SB4600-5 1/16 1/16 3/16
6
BBC 565 c.i.d. 14:1 kit P/N
Crank Forged 4.250 in. Stroke
Rod Forged H-Beam 6.385 in.
Forged Pistons 4.600 Bore
0 deck atC.R. @ 114ccC.R. @ 119ccPinRings
14:1 compression with 119cc, 14.7 with 114cc chamber, CLE-CB743HN rod, and CLE-MS829H main bearings
CMB-08-0097
KOT-012GAG425

KOT-012AG33654

WIS-K0245A100 42cc Dome

9.780

14.7
14Full Floating 0.990
JEP-JG770846005
.043bc, .043, 3mm

dart engine kit

Summit-Dart Short Block Engine Kits are built to perform in high-boost and nitrous applications. (Image/Summit Racing)

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9 Comments

  1. scott allen swope says:

    Sorry but I was looking at this because it was talking about the dart isn’t that a dodge? So what are you talking about chevy for I think I must have missed something. Thanks

  2. Too bad they don’t make Ford blocks.

  3. Anthony Walker says:

    I have a Dart 434 SBC in my 84 Vette here in Australia and I am still in the middle of finalising plumbing before its first fire up. I am very happy with the quality of this block and rotating assembly, but a little dissapointed with the Callies rods they selected…if they had of installed Callies Ultra Rods the Small Base Circle cam may not have been an issue with my build. Anyway the only other dissapointment I have is with their 230cc Pro 1 Aluminium Heads. The standard SBC header bolt pattern is drilled and tapped, but they also mark a Stahl Header pattern with counter-sinks…why not just drill and tap these? The heads are 230cc and usually anything running these will require big primary pipes anyway.

    Also, CW Hey, the do make Ford blocks.

    • Jeffrey viands says:

      Thanks for bringing that issue with the header bolts on 230 cc heads. I’m ready to use those pro 1 230 cc heads. Good catch…

  4. Daniel Wilson says:

    Dart does indeed make very good Ford blocks. Unfortunately I didn’t see any of them listed here. Maybe I will switch to GM…OR MAYBE NOT !!!

    I’m satisfied with Ford’s Superior Small Block Engine. The 351 Cleveland is making history…Again. For those interested, Cleveland specific blocks featuring full Cleveland architecture are currently being produced entirely in the USA with final machine work being done by the expert Machinists that are also the vendors responsible for bringing back this historic engine.

    The new blocks feature priority main bearing oiling systems to correct problems like the Pro Stock racers were experiencing with repeated blasts above 10,000 rpm’s. They have much thicker bulkheads for rock solid reliability in any application and plenty of material for large bore/stroke builds up to 500 cubic inches using the optional CGI blocks (Iron) , or for substantial weight savings they are also available in aluminum alloy.

    With a huge selection of alloy heads currently available from Australia and the States, along with some much needed EFI Systems being produced for Clevelands, I will have to pass on the common double hump, 3/4 race cam nonsense and stick with the New Old School Cleveland Superiority. The website listed has all of the details.

    TMeyerinc.com

    And the beat goes on…..

  5. Pingback: LMF 5.3L Engine Upgrade Guide: Expert Advice for LMF Mods to Maximize Performance - OnAllCylinders

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