377 small block ???????? rpm range
 

hello i am new to this sight kinda feel outa place still, as i have always raced mopar, BUT i have switched to chev this year for bracket class,i want to find out about a motor . it is a 400 block 350 crank with some kind of spacers manley alum rods and trw 12:5:1 pistons. i am running a 400 now 40 0ver 540 lift cam 5000 stall turbo 400 and car runs in mid to low 11s but? i am being told that this so called 377 can really push the rpms and produce better ets can anyone help me out here with your thoughts thanks alot.

377
 

I have run a 377 and I ran a best of 10.721 @127. This is in a Vega that weighs 2840 with me in it. I shifted at 6600 and crossed the finish line at 7400 rpm. Broke a rod bolt and ate the crank up. Still have the spacers somewhere. I was pretty happy with the engine. Definitely wound tighter than the 406.

Re: 377 small block ???????? rpm range
 

Alum rods can be spun higher, Everyone wants to go faster but more often then not spinning a motor higher breaks them faster. Like you said you are racing bracket, the best advice I can give you is focus on making it consistent and making it live. I launch,shift and cross my motor so it'll live a long time, not the fastest but lives. :D

A 377 is a good choice in my opinion. You should be aboe to take it to 6500-6800 if using a steel crankshaft and make sure it is balanced.
If using with Aluminum rods like already said you could go higher but I have no experience there.. Depending on weight and the whole combination it should be no problem breaking into the 10's.

I'd keep the 400.

All else being equal bigger will be better in most cases.

I run my 377" to 7200/7300 shifting at 6800. It's a 509 2 bolt block filled to the water pump holes with a good bottom end, 4340 Eagle, 350 mains with Bearing spacers, Eagle "H" beam rods with L19 bolts, and JE 13.5 pistons, and Track 1 heads. It runs 10.59 @ 125 and 6.52 in the 1/8 car weighs 3253lbs at Memphis. i have pulled the top end chip out and run it in a dragster 8.23 @ 158mph and 5.15 1/8, in fact we broke out with a 5.13 at the Super Chevy show at Memphis, all on Alcohol.
No issuses with over 100 passes.

Zip.

thanks for all the feed back its all really apreciated
 

now that i have decided to buy this short block, any sugestions on a cam choice that would work well, i am curentley runing a comp cam
pt#12-502-5 540 valve lift and 250 duration works well between 3000 and 6500 although i never ran it out the end at 6500 yet as everyone has told me a 400 wont take that rpm, seems to work well in my 400, any thoughts on this, along with the question i also got a tunnel ram with two 600 holleys would they work better on this or my single 850 holley????????
thanks again guys

Kinda depends on the weight of the car, i've run both a tunnel ram with 2 660 ctr. squirters and an 850. the tunnel ram was a little better on top end but suffered on the bottom end. I've ran .595 flat tappet cam to .660 lift roller cam. The one i liked best is .630/.630 roller all the cams have 106 lobe seperation installed at 102. All the cars weighed over 3,000lbs and run from 10.30 to 10.60 qtr. mi. By the way i run 5.43 gears in the Malibu so it goes over 7,000 every pass in the 1/4mi.

JMO


Zip.

Just a little note on your add that i saw forget the 377 (350/400crank)build yourself a 30 or 60 over 350 w 3 9/16 storker 6in.rod you will not have to notch the block,hitting the cam plus you crank it up 8000 all day and have just has much tork.enginekits.com sell one for less than $300.00 make sure you have the rotating assm. balanced. you need a piston with a compression heigth of 1.519 w/5.7 rod or 1.219 w/6.0 rod. this will be a 383 w/a60 over block.that'a 3.562 crank with a gain of 0.082 over stock.if your going spend money on spacers get a 400,block speedpro and com cams sell spacers that fit it for a 350 journals put in a 267 crank 3.10 stroke w/a30 over you'll have a 336ci.w/4.1555 bore thats what super stock cars use with a weight to cubic in ,rules