355 or 383
06-27-2008, 09:19 AM
#17
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Join Date: Mar 2004
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yes, for sure. Get n2o rings while your at it. Those two will allow you to use much more n2o safely.
Thats the biggest issue, guys build a motor with no n20 in mind and then once they gone as fast as possible NA, they want more. So a n2o kit is purchased, than they get greedy with that.
So before they knew what hit em they are spraying 150's, 200's on a forged shortblock that wasnt built for it.
Thats how they put holes in pistons.
Thats the biggest issue, guys build a motor with no n20 in mind and then once they gone as fast as possible NA, they want more. So a n2o kit is purchased, than they get greedy with that.
So before they knew what hit em they are spraying 150's, 200's on a forged shortblock that wasnt built for it.
Thats how they put holes in pistons.
06-27-2008, 07:50 PM
#18
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what kinda shot would i able to use if i were to get nitrous rings and forged pistons but still have cast rods and crank? and they say that the eagle cast steel crank is only food for 500 hp thats has to be like a safety line or something right? i love that good old NA power but i do like the sound of nitrous for when that ******* in a supra pulls up next to me thinking his turbo lag is my thought of a chance of winning lol when in realitly im blowing blue flames out of the exhaust paul walker style haha
06-28-2008, 12:44 PM
#19
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With a h+c 383 around 400rwhp/400rwtq a 125/150 would put you around 530rwhp and 600rwtq. n2o does a lot more in the tq dept. than hp. You want a very good exhaust setup when using nitrous. It will help you make so much more power.
07-02-2008, 07:07 PM
#21
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im getting the motor built and i wanted to know if the cc306 cam would still be good to use in the 383 or maybe i could advance it a little to compensate for the motors lower horsepower and tq peek and what should i expect to shift at
07-02-2008, 08:05 PM
#22
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Location: waterford, MI - USA
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the 306 would be an ok cam in a 383, but not ideal. if you wanted an awesome daily driver 383, then stick with the 306. it'll still rumble, and make good power, but not pushing any limits. Id expect it to peak at 6300 with some really nice heads. for max power though Id recomend a SR cam in the neighborhood of 250I/255E. or for HR 240I/250E. thats what I wish I could have afforded to do with mine. 383, home ported heads, 233/239 cam, =6100rpm peak.
07-02-2008, 08:33 PM
#23
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oh, and the problem with some 383's being dogs, or, not living up to the expectations, are they need more air flow for the same rpm. stock intake mann.s are a restriction IMHO and kinda the equalizer between a well built 355, and a 383 with all the same parts. atleast after say 5000rpm. below that the larger engine will kill the smaller one. so thats why 383's are way more driveable cause they got alot more power/tq down low.
forget about 7500rpm. I wouldnt count on shifting at even 7000rpm. you'll need a pretty stout everything to build a combo that will peak at 7000rpm. your talking about a very large cam, and the best of top end stuff. big$$$
forget about 7500rpm. I wouldnt count on shifting at even 7000rpm. you'll need a pretty stout everything to build a combo that will peak at 7000rpm. your talking about a very large cam, and the best of top end stuff. big$$$
07-04-2008, 11:05 AM
#25
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well, with stock ported heads, a huge solid roller would be a bit of overkill. unless you're building for the future. as someone suggested earlier. which is what I recomend. build the best short block you can afford, go with ported stock heads to keep cost down now, stick with the 306 for now too, then upgrade the heads and cam as a combo later when money is available again. cause the little stuff will nickle and dim you to death while your building the shortblock. I ported my own heads, built my own engine, and still ended up spending around $5K.
and if you did that, your combo would be very similar to mine. it was 383, eagle 4340 hbeam/crank, srp pistons, 10.8:1, home ported head/intake, 52tb, 233/239cam, 3800 stall, 3:42 gears. and I went 11.69 on a warm day, with lots left if I only had some more cash. my car was also almost full weight fully loaded car too. the gears killed me, that combo really needs 3.73's or 4.10's but it was an awesome driver, as I mentioned. oh, and if you do build it for spray, you can just shoot 150-200 and surpass the money you'd spend on a set of afr's and a solid roller whenever you want to.
ok, last thing to keep in mind, if ported stock heads (AI or LE) cost you over $1200, Id seriously think of getting the dart heads or look at whats avail. cause I know there are some reasonable cost heads out there, but they had 64cc chambers and with a 355, you'd give up too much compresion. with a 383, you would either go with a dished piston (-16cc is what I used) and stock heads, or you could use flat top pistons and the 64cc aftermarket heads. just some more things to consider.
and if you did that, your combo would be very similar to mine. it was 383, eagle 4340 hbeam/crank, srp pistons, 10.8:1, home ported head/intake, 52tb, 233/239cam, 3800 stall, 3:42 gears. and I went 11.69 on a warm day, with lots left if I only had some more cash. my car was also almost full weight fully loaded car too. the gears killed me, that combo really needs 3.73's or 4.10's but it was an awesome driver, as I mentioned. oh, and if you do build it for spray, you can just shoot 150-200 and surpass the money you'd spend on a set of afr's and a solid roller whenever you want to.
ok, last thing to keep in mind, if ported stock heads (AI or LE) cost you over $1200, Id seriously think of getting the dart heads or look at whats avail. cause I know there are some reasonable cost heads out there, but they had 64cc chambers and with a 355, you'd give up too much compresion. with a 383, you would either go with a dished piston (-16cc is what I used) and stock heads, or you could use flat top pistons and the 64cc aftermarket heads. just some more things to consider.
07-04-2008, 12:19 PM
#26
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thanks for the advice on compression im having my heads ported by a well known guy in my area that does porting for several speedshops i can afford a custom ground cam and i found a pretty sick deal on a fully forged shortblock 383. and i know the supporting mods are the things that really kill you with the throttlebody and the injectors and gaskets and **** its gonna be rough. i totally am going to have the rings gapped for nitrous for the future.what cc dish are the stock heads? and i feel like im dead with out the car its fourth of july and im sitting in my house main lining jack daniels cause i cant drive it lol
07-04-2008, 12:34 PM
#27
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pretty sure stock combustion chamber volume is 54cc.
what pistons (dome height or dish size?)are in that engine you found? that will dictate what cc your heads will need to be. also what head gasket you'll need. oh, and find out if the deck surface has been milled.
what pistons (dome height or dish size?)are in that engine you found? that will dictate what cc your heads will need to be. also what head gasket you'll need. oh, and find out if the deck surface has been milled.
07-04-2008, 11:20 PM
#29
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well, I found back when I built my motor that SRP had the best pistons at the most reasonable cost.
as for size, with stock heads, you got some choices to make. you could either use -16cc pistons, deck the block, and use .029 impala head gaskets (as I did,) or you could use the next size up which is something close to -6cc piston (forgot exactly what it is), stock deck height, and either the .029 or .040" head gaskets. you'll have to have your eng. builder tell you what would be best for you. and what he actual #s come out to be. been too long for me to remember the options.
I also recomend HE hellfire rings. gapped at .023 and .023 you'll be good to go with the nitrous.
I also recomend the 6.0" rod instead of the standard size so it'll make a bit more power, and rev quicker/less wear internally due to the better rod/stroke ratio.
as for size, with stock heads, you got some choices to make. you could either use -16cc pistons, deck the block, and use .029 impala head gaskets (as I did,) or you could use the next size up which is something close to -6cc piston (forgot exactly what it is), stock deck height, and either the .029 or .040" head gaskets. you'll have to have your eng. builder tell you what would be best for you. and what he actual #s come out to be. been too long for me to remember the options.
I also recomend HE hellfire rings. gapped at .023 and .023 you'll be good to go with the nitrous.
I also recomend the 6.0" rod instead of the standard size so it'll make a bit more power, and rev quicker/less wear internally due to the better rod/stroke ratio.