I bought a New Engine for one of my projects! I think this is really a decent deal!

[byndbad914]

sounds cool... specs didn't list the rod but it must be pretty short like 6"? Assuming a deck to 9.235" that would leave a 1.185" CH in the piston...

I am not a big fan of really low rod to stroke ratios and a 6" rod on a 4.100" stroke is a 1.46 rod/stroke ratio, which is rather low but nothing completely out of the ordinary (454 BBC are low like that as well). Keep in mind a 347 Ford stroker is typically 1.59 R/S for example.

For a street rod no big deal, just for a guy like me that will maintain them in the 5K-7K rpm band for extended periods on road courses, it is a bit rough on bearings and low compression height pistons to run such a low R/S IMHO. I prefer 1.6 minimum for sustained rpm with V8s of 5K-8K, so if you are considering sustained rpm with your project (don't know cuz it is "secret" and I appreciate that, my next project is secret as well) I would take that into account.

edit - and I state this fully aware of the LS7 having a short tho' higher 1.5 R/S and similar CH... I am just not a fan personally as I have seen engines with those low R/S values knock pistons out of them in race applications and show aggressive bearing wear.

[tyoneal]

Originally Posted by byndbad914

sounds cool... specs didn't list the rod but it must be pretty short like 6"? Assuming a deck to 9.235" that would leave a 1.185" CH in the piston...

I am not a big fan of really low rod to stroke ratios and a 6" rod on a 4.100" stroke is a 1.46 rod/stroke ratio, which is rather low but nothing completely out of the ordinary (454 BBC are low like that as well). Keep in mind a 347 Ford stroker is typically 1.59 R/S for example.

For a street rod no big deal, just for a guy like me that will maintain them in the 5K-7K rpm band for extended periods on road courses, it is a bit rough on bearings and low compression height pistons to run such a low R/S IMHO. I prefer 1.6 minimum for sustained rpm with V8s of 5K-8K, so if you are considering sustained rpm with your project (don't know cuz it is "secret" and I appreciate that, my next project is secret as well) I would take that into account.

edit - and I state this fully aware of the LS7 having a short tho' higher 1.5 R/S and similar CH... I am just not a fan personally as I have seen engines with those low R/S values knock pistons out of them in race applications and show aggressive bearing wear.

================================
Byndbad914:

Thanks for the response and information.

I have some information regarding the above numbers for accuracy.

I asked some specific questions and I was sent this:
=================
The connecting rod length is 6.125" which creates a R/S ratio of 1.5. We do not have any concerns of bearing wear at extended RPM's for your application.

Also, We have implemented new piston technologies including ring packages and piston coatings that improve ring seal and wear.
====================
As you have mentioned the LS7 also has a 1.5 R/S Ratio, this engine appears to be inline with that. I'm not sure what the average Ratio is for the LS Engine platforms, but this one is limited @ 7000 rpm, and they have done research with this particular package running for extended periods of time at high rpms.

I wanted something that would be strong enough to have a lot of fun with, and take it to the track as often as possible, and be able to run the Power Tour easily. Based on the parts that come in the engine, and their attention to detail, this looked like a nice package. Plus, for everything that comes with it a good bang for the buck.

I'm wondering if there is a substantive difference in the acceptable R/S Ratio between the Gen IV and the SBC's?

I am currently running a 400 SBC with 550 hp in my Camaro, and this LS3 427 running with the SS (Hotter) Cam rather than the regular HO Cam, will put out a good 50+ hp more than my SBC, but it idles with a nice lope at 650-700 rpm and 13+ pounds of Vaccuum, whereas my SBC Idles at 1100 rpm with 8-9 Pounds of Vaccuum.

I realize that there are 27 more cubes in the Gen IV Engine, but the manners are so very much different and the mileage one can expect with the LS3 is 3X's that of the 7 mpg of the SBC 400. The LSA in the 400 SBC is 108 degrees vs. 114 degrees in the LS3 427.

I think DSE just picked up one of their, "Race Prepped", LS3 416's. I'm sure they will be seeing a lot more events than I will, however the LS3 427 with a (Callies and Mahle) forged bottom end and ARP fasteners throughout, I'd be shocked if it wouldn't handle quite a bit of Thrashing and a nice kick in the seat to boot.

I am certainly open and interested in your knowledge of engines, and I hope you will give some more particulars of the SBC your running, and of course if you have some specific knowledge of what the big and small differences between the SBC and the GM Gen IV engines are, please educate me.

I look forward to your answers. (Hopefully)

Best Regards,

Ty O'Neal

[TOM NELSON]

Mast looks like they really have a nice set up going and have some neat packages but you should beware that the problem does not lie in a short rod ratio it is.It is in how far the piston comes out of the bottom of the sleeve ls motors are all including the lsx gm and warhawk world with the exception of the ls7 short sleeved motors around 5.5 inchs in length.When you put a 4.100 crank in that and have a compression height of 1.065 roughly you end up with problems because the pin for one where the compression height is measured will be higher than the oil ring so virtually all the skirt comes out of the bore within a few hundred thousands of an inch from the oil ring.The piston will go past gauge point and rock quite a bit when it goes to make the change to going up the bore and this will wear the skirts out super fast and wear the rings funny most likely start using oil in the near future because of this we learned this the hard way especially when making power you will shear the skirt right off the piston not fun especially when the crank is spinning inside the engine.Chevy figured this out with the ls7 and added over .300 to the bottom of the sleeves the fix this but the l92 ive seen are much to short.I would be concerned about this a ton of people are building these right now.But it is not the answer when you want reliabilty.When we build a 427 or larger We either resleeve it correctly or build it with the taller deck height blocks.or we won't sell it to the customer Many people will tell you its fine it is not.This is something everyone considering a stroker ls should consider because its exspensive to fix.

[tyoneal]

Tom:

Thanks for the response you are certainly correct about stroking the Short Deck LS Blocks. When I was speaking with their Engineers, we spent quite a bit of time discussing what the engine would be used for, and what I was expecting from it. These Engines evidently have been very popular with their clientele and for what they were intended to do apparently, they seem to be performing ok. These are listed in the "Hot Rod/ Muscle Car", part of their offerings, whereas, the 416 c.i. Engine that DSE just put into their 1969 Camaro, due to it's configuration and components is classified as a, "Race Prepped" Engine from the get go.

For me in this Project, I wanted to get something that would put out a lot of hp and use the super efficient LS Technology. Practically all of the higher horsepower Engines I have ever owned were used almost exclusively on the weekends IF the weather was nice. Probably like many people on this site I have also accumulated several cars to spend my weekends in.

I also drive a 1965 Riviera 425 Nailhead with 2X4's. It's also a blast to take cruising around. I picked up an older Porsche a Number of years back that is also a delight to run in. For this Camaro, if I could get some fun cruising in, and then be able to spend time at the tracks from time to time in the area to take some driving lessons, that would suite me just fine. As I had mentioned in a earlier post, I currently have another project right on the tail of this one, that I would like to get started on sometime later this year, plus I want to have some time enjoying this Camaro. It has the LD 3-Link, and I have just about everything sold by ATS for the Front End. With only a few upgrades to the front end this car handles wonderfully.

I know your engines, are practically legendary pieces of Art, with very much the highest quality parts money can buy in them, in addition to putting out Hoards of power, I'm sure they will last as well as anything that can be made putting out that kind of power. I'm not really sure how many miles the average person puts on their, "HotRod/Pro Touring", Car over it's lifetime, with one of the higher end Nelson Engines, but I would bet they are not usually DD's. If nothing else, at least for me, staying on my toes to be able to drive one safely around town would be something that would demand the upmost respect. I definitely wouldn't want to wrap myself around a tree.

With very few circumstances when have I ever owned engines that made 500+ hp (That weren't just huge in size and N/A) I have never expected to get 50,000 miles out of one without spending a lot more $$ upfront and sometimes up to 2-4 times what this one cost to either buy up front, or to have to replacing things that break or will wear out sometime in the future. The 1969 Camaro I decided to put this in currently has a 400 sbc in it. It's a nice sbc and puts out about 550 hp, but that said, as many high performance engines go, it isn't always as street friendly as one would prefer from time to time. It sounds great and really Hauls the mail when you put your foot into it. The one I just picked up, even with the larger cam they offer idles nicely at 750 rpm and is like a puppy dog compared to the 400. The sbc is much more of a Pure racing engine, while this LS3 is easily street friendly and also really responsive with you hit the "Loud Pedal".

Once again, I appreciate you taking the time to add to the conversation and who knows one of these days when I quit messing around with so many of these, I might very well give you a call and see what you have that would fit my need (or wants);-)

Take care and Thanks again,

Best Regards,

Ty O'Neal