Dart versus Man O War

[Martin Weigold]

Does anyone have any opinions as to what are the better blocks to use - Man O War or Dart? I am looking at using one of these aluminium blocks (to save weight) but with Gurney Weslake Heads (for originality). Do these blocks have any known issues?

Thanks, Martin

[DBLDREW]

Pick the least expensive one. Both of those blocks are very strong, and as you build more and more power, your transaxle will fail long before you come close to the threshold of splitting one of the blocks. A chain is only as strong as it's weakest link.

[Dean Lampe]

I am curious, where did you find those heads?

[Sandy]

I don't have a Man-o-war but I have an SVO and Dart Aluminum block. Both are similar, the Dart does look a bit beefer but I think that may be just the look. Both will require some fair amount of extra machine work and prep of the block (or you will pay in the price of the block if done).

I think the cost is a factor, I got a good price on the Dart block, but I think they have since cracked over the 4k USD mark. Not sure how much the SVO is these days, but it is more of a pain to get as I think it comes from only one source (RDI). The dart is easy to get and likely the World is as well.

I don't think you will have any trouble with any of them, they are all pretty strong, and nice an light, and as mentioned cost and availability or brand loyalty can help guide you.

Check the link below, you will find one that is under construction on the Sunbeam Tiger page, and also the GT40 Photo link pages somewhere in that site. Both are Dart Blocks. The Mustang that is up has the SVO, and it does take a beating.

Sandy

[Chas]

Originally Posted by Martin Weigold

Does anyone have any opinions as to what are the better blocks to use - Man O War or Dart? I am looking at using one of these aluminium blocks (to save weight) but with Gurney Weslake Heads (for originality). Do these blocks have any known issues?

Thanks, Martin

Martin,
I may get shot for mentioning this but-if you seek originality, both our block and our worthy competitor's have expanded water jackets which add shapes and slight bulk to each bank. So they don't quite look "original".
As far as weight, Man O'War 9.5 deck weighs 108 lbs with caps and sleeves. A complete 427 with our heads weighs 399 lbs. I've not yet weighed an 8.2 but I will soon.
We've seen numbers between 625 and 638HP with our pump-gas 460 aluminum builds, so I think your transaxle will be OK at 500 to 550HP.
Unless you build a 460...

[Martin Weigold]

Chas

Thanks for this info. The Dart aluminium block weighs only 83 Lbs with caps and sleeves according to the sales guy I spoke to. Where is the difference in weight between the blocks if the Man O War aluminium block (8.2" deck, 4.125 bore) is 108lbs with caps and sleeves?

Also, do you have any pics of the aluminium blocks with the expanded water jackets so that I can see what you mean in terms of their look.

Many thanks for your help

Martin

[Sandy]

Martin -

I think an old thread had weights of the SVO and DART (No Man O' War at the time) in iron and aluminum.

Take a look at Home of GTSparkPlugs.com Go to the cars button and look at the Tiger pages I think you can see the side of the Dart block on the engine stand. Also they are easy to spot vs. the Iron versions of stock 302's. Freeze plugs, different Oil sender area, and the shiny color give it away. If you are trying to squeeze it by a tech as original likely will not happen. The SVO aluminum blocks also have a nice Tattoo on the front of the block.

Sandy

[MikeP]

Hi Martin - the weight given by Chas for the Man'o'war block was for the 9.5" (351 size) block. This is probably why it is 108 pounds. He has not got a weight for the 8.2" (302 size) block yet so you can't compare like with like until you get that figure from him.
There are some pics of the Man'o'War 351 size block on the thread he set up a while back to anounce them. They may help you to see the difference in the outside shape of the block compared to the standard iron item.
Cheers
Mike

[Chas]

Originally Posted by Martin Weigold

Chas

Thanks for this info. The Dart aluminium block weighs only 83 Lbs with caps and sleeves according to the sales guy I spoke to. Where is the difference in weight between the blocks if the Man O War aluminium block (8.2" deck, 4.125 bore) is 108lbs with caps and sleeves?

Also, do you have any pics of the aluminium blocks with the expanded water jackets so that I can see what you mean in terms of their look.

Many thanks for your help

Martin

Mike is correct, I gotta weigh an 8.2 when the production blocks arrive. No sense weighing a PPAP block as often they're not completely machined or require revision.
We won't win any diet contests with ours for several reasons. First, it's a clone of our iron version which weighs 213lbs (9.5) That's handily heavier than a standard 351 for instance. We know of a customer's 400ci build which is just shy of 1750HP (boosted) and another's who runs regularly at 9000RPM and approximately 1200HP. So the bulk pays off in iron.
The alloy version is the clone with some additional webbing in the valley and rear bulkhead.
Second, there's added weight in the alloy due to the additional bolt bosses at the 12 and 6 O'clock positions for the 6 bolt-per cylinder attachment. Of course, the expanded water jacs too. So that changes the shape as well.
To save you a search, here are two views, to hopefully help. Just shot the one on the engine stand and they're both 9.5's.

Here's what you might see in a GT engine bay:

Minus the Frankenstien wires...
These are our 18 degree heads which are like other aftermarket heads in that they employ 4 bolt-per cyl. attachment. So you see the unused bolt bosses.

[Martin Weigold]

Chas,

Many thanks. I won't be doing over 600 HP so the Dart aluminium block should prove fine for me.

Thanks for everyone's input

Martinh

[Frank Catt]

As I will be fitting this engine to Martins car, can you tell me whether the engine mount lugs are in the stock 302 position, Thanks, Frank

[Chas]

Frank,
For the record, ours are and I believe Darts are as well. Several friends have Darts that fit numerous chassis.

[Sandy]

They are on the Dart and SVO and I would assume on the MOW block to. One thing to watch out for is the Screw in oil galley plugs and freeze plugs may interfere with some of the motor mounts. I had to do some grinding on some aftermarket ones (TCP on the Mustang), not sure if this is true for stock style, but not bad at all.

Sandy

[John]

there's added weight in the alloy due to the additional bolt bosses at the 12 and 6 O'clock positions for the 6 bolt-per cylinder attachment.

i've seen the blocks with the additional head bolt holes, but never a head for a SBF that utilizes a 6 bolt attachment. Who makes a head for this?

[Chas]

John,
We do. It's the Man O'War 10 degree aluminum head. Unfortunately I'm unable to post a link in this reply although it worked fine earlier when I posted the photos above. (Help Mods?)
The head and it's specs can be seen on the sites in my sig by clicking :
Products
Cylinder Heads
Man O'War 10 Degree Aluminum
A CNC version in a joint effort with Jim Kuntz produced 420 CFM. It's for very big boost and sheet metal intakes. There is a thought here to change tooling on our more conventional 18 Degree (also seen on the sites) and have it be 6 bolt attach also.
Sorry can't show you the Photobucket images I have but maybe I'm banned from putting pics up??

[Ron Earp]

Chas nothing has changed on picture posting. If you have a URL you just click the little picture icon above your edit box (you need to be using the WYSIWYG editor, check that in your User CP) and paste the picture link in there. It'll show up.

[Chas]

Thank you Ron, I'll try that. I'd like to add to your Rep Power but you'd have 5,100,001!

[Chas]

No luck Ron. Netscape here at home won't let this work. If anyone cares I'll post links or pics from the shop on Monday.
(

[Ron Earp]

Nothing has changed with pictures, it must be with your firewall, permissions, or something like that.