Little M input

All right, you guys have this Gen 1 think really biting at me now.

I was going to run the LT1 for the reverse cooling but I guess I can plumb it externally and get the same effect and have a better block as well so I'm about to jump. I just have a couple questions.

Things I was going to do to the LT1 block:
Lifter index
Cam bore trued
Bores Indexed
4 bolt splayed and all 5 billet caps
Half fill
Maybe roller cam bearings
Decked
Valley stands
Valley screens

So if I get the Little M block would I still need to do all of this or is it all done when it comes?

Please speak from experience as I know what the sales brochure says, I'm juts curious as to how accurate what they put out is, or if I will have to do it all again$$$$

I'm thinking of 350 mains and a 4.125 bore. I already have a real nice crank and rods out of Steve Quinns old motor(Cola, Eagle L19) Would this work in the Little M, the crank is a one piece :(

I figure that much more bore with a relativly short stroke would make a nice drag motor.

Any input??

Lifter index: Should not be needed on the M and probably not needed on the stocker (can be checked).
Cam bore trued: as above.
Bores Indexed: as above.
4 bolt splayed and all 5 billet caps: the M has 'em.
Half fill: a matter of preference for the M, I'd do it on a stocker hi-po buildup.
Maybe roller cam bearings : not unless this is a MAX effort buildup.
Decked: The deck height on the M is 9.025”. It should be true, but needs to be checked. If you want a different deck height, that's another machining operation needed. The stocker needs it.
Valley stands: do not come with the block.
Valley screens: ditto.

The M is for a two piece rear main. It is not ready to assemble. Needs a finish cylinder bore/hone to desired size/finish and the mains should be aligned honed to desired clearance. Everything else should be checked. As described above, may need to be decked. Should you have to do this for what they charge? No, but you do. Locally, going to the best local shop (which is very good) it costs $5-600 up to have an aftermarket block prepped. Buddy just did a Dart BB, mnachine shop bill was ~$700 including local pickup and delivery. Stock block prep will go for ~$1,000 up depending what is done.

The thing that was surprising to me when I learned it was that the aftermarket blocks are not plug-n-play. Quite a bit needs to be done to get one ready. And if you are building a motor stout enough to need one, checking everything a number of times is a damn good idea anyway.

Rich

Hmm so whats the big advantage?? I'm planning on getting as close to 1000hp at the flywheel as I can, with alot of nitrous being used.

Is the stregth difference gonna be worth while at my moderate power levels?

Will the one piece crank even work in the Little M?

Get a GM Bowtie block or a Dart block, better quality than the world products stuff...and you can get them for a one-piece rear seal.

Little M is a Dart:confused:

A 1,000 is not moderate hp for a small block. Yes, a better block (Dart or Bowtie) is a good idea. It will run ~$1,000-1,500 more than a prepped stocker. Considering the overall cost for a reliable 1,000hp SB, that is not significant.

Rich

A 1,000 is not moderate hp for a small block. Yes, a better block (Dart or Bowtie) is a good idea. It will run ~$1,000-1,500 more than a prepped stocker. Considering the overall cost for a reliable 1,000hp SB, that is not significant.

Rich

Thats what I was thinking.

I was budgeting about 2500 for the block itself, and I have seen the Little M with the billet caps new for ~1600 so I should be able to get it on budget.


Anyone else have any input or experience here??

Get a GM Bowtie block or a Dart block, better quality than the world products stuff...and you can get them for a one-piece rear seal.

Which Dart block has a one piece? I looked through there catalog and didn't see it.


But the 1,000 dollar question, will my one piece crank work in a 2 piece block?? I have a really nice Cola crank that I want to use and I got a screaming deal on it.

I looked for a bow-tie block and they seem rated very low.

I have heard a LT1 blocks can handle 1k HP but these "race blocks" are rated to 850??

I take it these are very conservative numbers??

http://www.gmpartsdirect.com/performance_parts/store/catalog/Category.jhtmlCATID=628.html

here the link to all the bow tie blocks, of which the highest rated 1 piece rear main will handle 450hp, I am hoping these are super conservative, as an LE2 package makes more power than that.

Yeah - I got the Little M and Motown mixed up, I am used to them being called Iron eagle so I just call it by the manufacturer, dart, GMPP, etc.

Here:
http://www.sdparts.com/product/12480175/4117quotBore350MainsCastIronBowTieSportmanBlock.as px

I use this block a lot, very nice out of the crate.

Yeah - I got the Little M and Motown mixed up, I am used to them being called Iron eagle so I just call it by the manufacturer,


Little M and Iron Eagle are different blocks, both by dart. :confused:

Little M and Iron Eagle are different blocks, both by dart. :confused:

Yes....? Like I said...I am used to associating Iron eagle with Dart, I have not used the Little M block only the Iron eagles - So when I saw M, I thought of the lower quality Motown blocks that have come across the bench. All of our modifieds and road race cars use Bowtie blocks, several sprinters have the Iron eagle block.

Yeah - I got the Little M and Motown mixed up, I am used to them being called Iron eagle so I just call it by the manufacturer, dart, GMPP, etc.

Here:
http://www.sdparts.com/product/12480175/4117quotBore350MainsCastIronBowTieSportmanBlock.as px

I use this block a lot, very nice out of the crate.

How much work does that block usually require to get it close to what a fully blueprinted stock block would be in terms of accuracy??

I looked at the link you posted and it says it is the same as block number 24502503 the only difference being the 1 piece seal. But when you loook up the 24502503 it says it comes with 8620 steel caps, and is rated to 700hp@8500. The block you listed says Nodular mains?

Will this block hold what I am going to do to it, or do I need a rocket block??

I plan on being as close to 700hp N/A as I can and then spray the difference.

Does anyon e know if a one piece rear seal crank will fit in a two piece rear seal block?? Anyone??

You can get an adapter to use an old style crank (2-pc. rear main) on a new (1-pc.) block, but not vice versa.

You are getting to hung up on this block thing. People have made 1,000hp on well prepped stock blocks. But given the cost of a project like this, the vast majority of people doing it will opt for the aftermarket block. The additional cost, in light of the total, should not be an issue. It's easier to get big displacement with an aftermarket (or Bowtie) block and they are stronger. But no 1,000hp small block is going to have OEM levels of reliability anyway (unless you drive it like a Granny). The parts are just too small and the stresses too high. Pay no attention to these "ratings", they are completely undefined. No one knows what they mean.

The "Rocket" block is machined for a 2-piece seal. It approaches being an "exotic" piece though with raised cam bores and spread oil pan rails, etc. I think you need to discuss your goals as a whole package with an engine builder - you are getting to much of your info from the Web, IMHO.

Rich

Screw it I'm staying LT1. I have talked to a couple local builders and they said it would hold with which ever I used.

Just seems kinda silly to me to drop 1500+ on a block only to pay to get it machined correctly which I can do with a block I already own.

Someone please correct me if I'm wrong but one of the advantages to an aftermarket or Bowtie block is the "stiffness" of the block as a whole. Where a stock block might start to distort the cylinders at higher power levels an aftermarket block would flex less, and thereby allow greater power production.

Again, I am not 100% sure on this matter. I think Rich would know more than I do, having actually built motors to withstand that kind of power.

When you get to very high cylinder pressures, having thicker/stiffer cylinder barrels will distort less and make more power. If cylinders walls get too thin, not only can they flex but they can crack. That's why it's generally recommended for production small blocks to not go more than 30 over on the bore and 60 for big blocks. None the less, there are lots of small blocks out there more than 30 over and big blocks more than 60. The BB in my race car is 70 over. Would it make more power at 60 under? Maybe a couple of hp. Significant differences in cylinder distortion or splitting is much more likely with high boost or even more so with nitorus due to the high cylinder pressures.

How thin is too thin? And how much can you overbore? Well, different people have different ideas on cylinder wall thickness. A decent rule of thumb for a SBC is 0.140" for NA and 0.180" for boost/nitrous. If high boost/big nitrous is contemplated, 0.200" is better. There is a lot of variability in stock castings. That's where the 30 over number comes from - it ought to be safe on any block without sonic checking because the nominal wall thickness at stock bore is 0.225", or so I have been told. I bet this changes from time to time and the only way to know for sure is to have the block sonic checked if it si going to have a big overbore.

A big advantage of the aftermaket and Bowtie blocks is cylinder wall thickness and quality control. They are thicker and have less variability. The Dart is a minimum of 0.275" thick at a 4.185" bore. So, lots of them are built to a 4.25" bore. BTW: Dart makes the GM Rocket block. I am not sure if they also cast the Bowtie? One way to help compensate for thin walls is a partial block fill. I regard this as SOP for a high po motor bored more than 30 over. Doesn't hurt even on a stock bore though. Keep in mind that you can't just fill the block and assemble the motor. It need boring and honing AFTER the fill.

Rich

The block I have now will clean up at .020 so I should be good, and we are doing a half fill.

Both of the local guys I talked to said it would be OK with what I am going to do.

The block I have now will clean up at .020 so I should be good, and we are doing a half fill.

Both of the local guys I talked to said it would be OK with what I am going to do.


Agree - should be ok for almost anything. Don't worry, be happy :) Or, is that "what, me worry?"

http://fasterthantheworld.com/alfred_e_neuman.jpg

Rich

Agree - should be ok for almost anything. Don't worry, be happy :) Or, is that "what, me worry?"

http://fasterthantheworld.com/alfred_e_neuman.jpg

Rich

Ok Rich I will quit worrying and just put this thing together :)