have a question about building a motor.

[emtb85]

Getting ready to build a motor and have a couple questions. I'm building something out of a 400 block. I have seen the post about getting a after market block but my rules states that our blocks must be a oem manufactured block. What's the best solution for this? My other question is the bottom end. What is the benefit of having a ligther rotating assembly. Is it worth putting the money towards it or getting a regular rotating assembly and putting the money some where else in the motor. Thanks

[DANNY]

It all depends on the rules as a whole. Pretty much everyone's going to say they need to see the rules, both engine and car.

[emtb85]

Car has to pretty much remain stoc, aloud to run racing springs and shocks but thats pretty much it.Has to weigh 3500lbs after the race. Motor has to be oem block and cylinder heads. No aluminum. Got to run 2bbl no roller rockers or anything. Aloud to run headers.

[Racer111]

alot of rules a bowtie gm block is considered oem

[racin6mod]

with those rules I would go with a 352 or a 377 cu.in. they seem to work well in 2bl classes.

[emtb85]

Is getting a ligthen crank worth the money or staying with the standard weight

[72Dubya]

Is getting a ligthen crank worth the money or staying with the standard weight

Yes it is definitely worth it. Less rotating weight allows motor to spin up faster, gives you a bit more torque and some HP. You want every little bit you can squeeze out of a 2 bbl motor. x2 on the 377 as well. Great 2 bbl motors.

[emtb85]

Thanks guys. Ill check into the 377. I know most of the guys there are running 383, 406 or 421.

[72Dubya]

Thanks guys. Ill check into the 377. I know most of the guys there are running 383, 406 or 421.

If you do go with the 377 route, definitely get a crank built specifically for it, not a 350 crank with crank spacers in your mains.

[72Dubya]

I ran a 377 on 2 bbl for awhile and it was probably one of the best motors I have had in a 2 bbl. Turned 7300 no problems. Also a guy around here that ran a 352 in for awhile this year that was stomping everyone in the SS class around here.

I have just always been raised on the premise of "NO SPACER BEARINGS" lol, but hey, if it works it works, and I am not going to argue with that!

[emtb85]

My other question is I'm wanting to run vortec or bowtie heads but will I be able to put a 2 barrel intake on them or will I have to do something else

[speedbuggy]

My other question is I'm wanting to run vortec or bowtie heads but will I be able to put a 2 barrel intake on them or will I have to do something else

I can't speak about Bowties, but, if you have to run cast iron, a 2-bbl Vortec intake can be pretty difficult to find and expensive when you do find one. They only came as a "marine" intake and they weren't labeled as a GM casting. It has "Mercruiser" cast right on the intake. A lot of whether or not you can run it will depend on your rules and tech inspector.

www.castheads.com (Brzezinski) may have one you can take a look at.

[emtb85]

The rules just state it has to be a 2barrel intake. The marine ones are allowed. I havnt ever delt with the chevy motors but people have told me they didn't think you could but a 2 barrel on eithe set of heads

[emtb85]

Well things has changed and the track I was gonna run at shut down. So now my new question should I go ahead and run the bigger engine like the 421-434 or should I go to the 358-377-383. Then track I'm running at now still wants the cast iron heads but we are allowed to run 4bbl and roller rockers.