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Post by modzilla28 on Aug 20, 2013 1:10:57 GMT -6
I was wanting to build a motor that will compete against a 421 because I can't afford an aftermarket block. I've built 383 engines in the past with no luck. Someone suggested I build a 362 with lots of lift and compression with a good set of heads. Said he knows a guy that is just killing everybody with one. I run a modified so the weight is 2400 lbs. He said the 362 is also in a mod. Is this possible or is he feeding me a line of bull. I race on a 3/8 mile fast semi banked oval. Any input would be a big help.
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Post by ljsracing on Aug 20, 2013 14:36:02 GMT -6
Motor size has little to do with building a motor. Its just a number. It comes down to 1 What is affordable. 2 what is most bang for your buck 3 can you hook it up? 4 does all the pieces work together.
Ive had a couple of 383s and i wouldnt of ever traded them for a 421. I race with some 400+ motors and ive yet to say i need more hp. And my motors arent a 10k piece. They just work with the parts i put in them. It runs and it runs good.
my first ? on a 362 is HOW are they building a 362? 3 9/16 stroke crank? 400 block 327 crank? compression (within reason) is cheap hp. For a mod you always want to shoot for 12.5-13:1 i think anymore is a little over kill but there is people that do it.. Lots of lift you have to watch clearances but its not a bad thing. What you have to watch is your duration. Thats what really makes the motor work. There is tons of options out there.. A plain 355 a 406 a 377 a 383 396 362 What fits your budget and what kind of track? What parts and pieces do you have?
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Post by Deleted on Aug 21, 2013 12:39:35 GMT -6
I agree with the above statement, size doesnt seem to matter in this case, LOL. A good flat torque curve is so important in a mod, and that comes from your cam choice and can only be figured out on the dyno through trial and error. I run a 18 deg 400 big bore short stroke motor. we have 11,500 in the motor where most we run against have 25k and up! We make good power, north of 700 but have never been out motored. Ya our motor aint cheep by some standards, but its a junk yard motor compared to who we run against. We gave Kenny Wallace all he wanted last month and he is running a Toyota Cup Motor in his Mod. That thing was worth more than my car, trailer and truck combined! My point is you dont have to be the most expensive to compete. A stock block 383 would be my choice, I hate stock 400 blocks, they are all junk, so I would use a 350 block with billet main caps, 4340 crank and some good H beam rods, with a solid bottom end, you can now build on that to make your power. I think a smaller motor that can turn more RPM is a big advantage. You can run more gear and come off the corner harder and have better throttle control with more gear.
Dave
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Post by modzilla28 on Aug 25, 2013 13:33:26 GMT -6
I run on a fast hooked up semi banked 3/8 oval with longer corners than straight aways. I got a good 350 four bolt main block in my garage cleared and ready for the machine shop. My last motor was a 383 it had dart iron eagle heads 2.02/1.60 64cc. 210 cc intake runners. I had a speedway tight lash flat tappet solid cam .510/.520 106* lca had 11.5:1 .100 dome pistons and a cast nodular steel crank and 4340 scat I beam rods topped with a 7500 rpm single plentum high rise intake and a AED 750 HP carb. I was close I run them down in the heat races but in the feature man those big cube engines shined. I was thinking about building this one with a set of dart 49 cc heads 2.05/1.80 235 cc intake runners. Fully forged with 11.5:1 flat tops this combo will make 13.5:1 compression a .635/.635 106* lca comp solid roller camshaft with roller lifters. Same style intake but with a 850 HP carb on top. I wanted to know if this seems like a good combo. All the internals will be balanced at the engine shop of course. If I use billet steel main caps in stead of splayed will that make a difference? Also what kind of RPM'S would I be able to turn with this set up and not plaster my new beast all over the race track? You guy's are a great help I like hearing your comments especially when I need help.
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Post by Deleted on Aug 25, 2013 14:16:57 GMT -6
Any motor is only as good as the lower end. Anything you can do to make the lower end stronger is going to be money well spent. The Stock block 383 I ran last year turned 8000, We put 45 nights on it with no problems. The Billet caps are always going to be stronger than the stock splayed type. Like I said before, money well spent. Ill give you a tip on carbs. We run one of the new Holley Ultra HP 850's on our motor. Best carb for the money IMO. Was around $700 new, we dynoed it against a Braswell that cost more than twice as much and were within 5 hp. I love that Holley HP, All billet body and metering blocks and weighs 5 lbs less than other carbs. Cam choice is going to make the difference for you, and I always leave that to my engine builder. He doesnt tell me how to set up the car, and I dont tell him what cam I need, LOL! The smaller CC heads will help, we were close to 15-1 on our motor. A good engine builder is key. Dont try and save a few dollars, it will cost you in the long run.
Dave
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Post by modzilla28 on Aug 26, 2013 18:41:52 GMT -6
Thanks I will keep that in mind. Can you PM me a good cam grind to use. I'm a little confused on what I need to run. I think a 8,000 rpm cam would be alright if your out front in clean air but in traffic it seems to me it would bog down and lose power. The most I ever turned was 7,200 with a 6.20 gear. Was thinking about going to a 6.33 but it seems to me that would still only put me around 7,600. If igo to a big cam do I just keep changing gears until I hit 8,000 just before corner entry? Just curious how to do that.
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Post by Deleted on Aug 27, 2013 8:16:47 GMT -6
I have no Idea about the cam choice. I stopped building my own engines years ago after they got north of 500hp. I will tell you that with a high reving 383 I always ran more gear than most. When others were at 6.20 I was at 7.00 on a 1/4 mile track. The bigger gear gives you the edge off the corner where the race is won or lost. It also helps with throttle control as the tire is spinning slower and responds to throttle change faster. I know my engine builder changed the cam grind every year, he was endlessly working combinations on the dyno and changing intakes to get a flat torque curve.
Dave
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Post by ljsracing on Sept 5, 2013 12:53:32 GMT -6
I would keep the compression under 13:1 it will help the motor live. You want to be high 12s for sure but the higher over 13 you go you are making it work harder. As for cam not familiar with roller stuff but bigger isnt always better. I prefer a smaller duration with less lift (you can always put 1.6 rockers on to make lift back up) than a big monster. If you build a good combo with more HP you will be shocked how many more RPMS you will turn with the same gear. Call a good cam company.. I like comp but They like to go BIG like REALLY BIG.. So maybe take what they say and ask the next size or 2 smaller. Sounds like a decent combo of parts. (other than cam. I have no input on it)
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Post by lizardracing on Sept 8, 2013 12:07:35 GMT -6
A custom ground cam by a real cam grinder is only a few dollars more but nets more drivable power than the generic lobe recommendations the Comp Cam phone tech finds in his computer.
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Post by the4car on Oct 20, 2013 19:33:39 GMT -6
Im new to this board but I am looking for the right combination for a sbc 383 build for next years season. We have to pull atleast 15 pounds of vaccum and run a two barrel holley. I have a sbc 350 block thats a high nickle 010 block and I have a scat 383 crank thats internally ballanced. I know that I need to do prep work on the block but needing help with the rest of the build. Any and all help will be appriciated. I run a 3/8 mile track with medium banking. Again, thanks.
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Post by Krooser on Nov 16, 2013 22:31:33 GMT -6
For the first time in almost 30 years I'm putting a SBC together for my son's recently purchased WISSOTA Midwest Modified. Here's what's going together… remember we have some strict engine restrictions to work around.
SBC 010 block .030 with all the usual prep work done. SLP super light pistons with a low tension ring package. GM LT1/LT4 powdered metal rods with ARP rod bolts. Stock GM steel (not cast iron) crank. ARP main studs. Zero deck height. Camcraft camshaft custom grind… not sure on the EXACT specs but it will be a solid lifter grind using hydraulic lifters with around 250 duration @.050 with .550 lift on 108/109 lsa. Chrome moly pushrods. 1.5 rockers.
The heads are GM iron 882 75cc (factory) with SI stainless valves, 5 angle valve job, Isky springs with 130# on the seat and 350# open pressure, 7 degree Isky retainers. Cast iron GM intake. MSD dizzy. Compression to be determined… rules say 9.5-1.
We are new to this mod deal (my last mod was raced in 1987) so we don't have many details but we figure we'll run around 7200 RPM's with this deal. My kids home track stays pretty heavy thru the night and only slicks up during the final 5-10 laps of the MWM main. The big mods run after the MWM's.
I'd suggest you run as much compression as you safely can and call Camcraft or Jones Cams for a good racy grind… off the shelf grinds just don't cut it.
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Post by flipflopoo1oo on Feb 27, 2014 17:13:09 GMT -6
It's hard to compete with the horses in the cubic inches on 3/8 as the pulling range has to be wide to compete with the gear change to try to bridge the gap! We ran against a 421 limited late on a quarter mile with all the good stuff and a close second but not under forth for the season with our 362! A de-stroked 400 was our best choice 384 in the mod class, 7 years running! While only 11.5 on alky it never stopped turning at 83-87 hundred with the lower compression! Tit for tat with the gears for 3/8 and compression! Burns slower with less compression but gives a longer burn time moving the crank farther for a boarder pulling range! Controlling temps is a must to fuel expansion with low compression! Do not run a power valve in your carb. as it will cut the fuel back with low gears when not in a strain on top-end! Consult your carb. mfr. for extra jetting tips! Do your own research on rpms and compression on fuel factors and heat! Good luck with your build!
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