texada

iTrader: (3)

How much more torque will this 4.250 stroke make over a 4.00 inch stroke with a big 4.185 or 4.200,heads & intake, cam, the same. Please give your experiences and advice.

Beast96Z

iTrader: (21)

26 cubes is a good bit. All things being equal I guess it would depend on if said heads/intake were already maxed out or not. Under curve power would come up a good bit, but the 4.250" wouldn't be good for high reving. It more or less depends on what your trying to do.

racer7088

Torque is displacement dependent so you will get basically the same per cent more TQ as you are stroking it.

Power on the other hand is mostly airflow and fuel dependent so the new larger engine may or may not be more powerful.

The bigger stroke engine will make the same or more power but at a lower rpm but if you want even more power you can further improve the heads and/or run even a larger cam in the newer larger stroke engine for even more power.

Saying all that though you can't just put a 4.250 stroke in any engine without making other compromises but it will go into a sleeved engine with longer sleeves and a shorter piston if all is designed right.

WizeAss

iTrader: (5)

what are your thought if you change the argument to 4.1 vs. 4.0 cranks????

Beast96Z

iTrader: (21)

Basically the same answer, accept you can run a 4.100" on a stock sleeve. It wouldn't leave the "optimal" ring pack, but it can be done. Having a good piston design will help in the longevity of the motor if you decide to do it with a stock legnth sleeve. Like I said earlier, power will be relivant to heads/intake being utilized.

racer7088

Yeah I am doing several pistons that will work like this. I am just finalizing my rings.

Ryne @ CMS

iTrader: (10)

he didnt ask you

racer7088

Beast knows his stuff too!

racer7088

It also depends on if you want something to take a 250 shot or if it's NA with maybe only a small NOS shot every once in a while.

NOS destroys everything basically so parts have to be made way more stout or they fail very quickly if anything goes wrong.

Ryne @ CMS

iTrader: (10)

just like to give him crap

WizeAss

iTrader: (5)

fixeded for ya bro!

WizeAss

iTrader: (5)

at minimum I am looking to run a 200 shot thru a 90mm TB/Intake plate kit. I will go thru about 1 bottle every couple of weeks or less. Just enough for 2 times at the track a month and 1 or 2 trips down the street for money races. Curious if those 4.1 pistons can hold up to this kind of nitrous. If not I will likely just stick with a 408 vs 418.

Erik, Let me know if ya had a chance to look at that 346 sittin bagged on the floor.

texada

iTrader: (3)

Beast96Z

iTrader: (21)

That's it. No unicorn pictures for you.

I take a few notes.



Yea, he thinks I'm teh sexy. I get that here at home to.


Not sure on the ring packs Erik is working on, but a 200 shot on a short ring stack isn't going to be very nice. I would say maybe a 100 shot on a occasional basis, but not much more. I'd look more towards a 408 with a nice thick deck nitrous piston, and maybe up your shot 25 hp or so.

Well, the question has pretty much been answered. At least were still talking about stroke. Kinda.

Chicago Crew UnderBoss

iTrader: (1)

I know many top engine builders who prefer a 4.00 stroke in a LS series racing type motor (especially over 4.250 monster stroke) especially on a motor that will be seeing rpms up to 7500, as their is less oil usage issues, faster revving=better racing motor, better engine geometry and longevity, etc., etc. There is a reason why the GM race Cars (C5R and C6Rs) use no bigger than 4 inch stroke!! I have also had an top engine builder that built me a 427 iron motor utilizing a 4.125 Callies crank on a 4.060 overbore and that Crank failed big time (reluctor wheel broke and crank welds) and i don't think I will run larger than a 4.00 stroke in the 454 LSX motor that I will plan on building this year, after that wonderful experience!! That old iron 427 motor of mine also used oil like a sive

Beast96Z

iTrader: (21)

I think I mentioned this before, but the Callies cranks had a problem with the welds on the reluctor wheels a while back. I personally don't think that your crank broke just because it was a 4.125". The oil consumption I can see, but pistons advances have been made over the past year or so. The major key to the long stroke is having a sleeve that can support the piston at BDC. In stock sleeve legnth applications, this isn't utilized to it's maximum.

Erik was great in working with Wiesco on getting me a piston that would be very reliable in the long run for my 4.185" stroke 454. Ring spacing and skirt shape were some of the major things they worked on. After talking alot with Erik and some with Brian@ wiesco, I can't foresee this being a problem motor, but only time will tell.

racer7088

Unfortunately most of the people building the big stroke motors hardly know/knew what they are/were doing and that's why there's as many problems as there are/were.

I have seen no real problems with the bigger cranks when done right.

WizeAss

iTrader: (5)

well..... if the 4.1 means no 200 shot, then I personally will stick with the 4.0 crank.

It is not worth sacrificing over 100 horses for the additional 10-15 you gain NA.

racer7088

It's getting close so I would stay with the 4.000 if you're focusing on NOS.

tlaselva

Stay away form anything larger than a 4.0 stroke.

My Callies Crank in my 447ci had major reluctor wheel issues after only 2000 miles and motor had to be taken apart.