Do a search here for 383 build, there is a kazillion of them and tons of information.
The block I have isn't machined to be a roller block. Also, if I used this carb and was just careful about the throttle it would still be fine for street use right? I ask that because I already had the carb and cam. I got them for a cheap price from a guy that was upgrading. The carb is a little used, cam is new of course.my87Z said:i personally like double pumpers as well, but only if the vehicle is being built to do some racing too, if it is being built for mainly the street then the vac secondary carbs will save gas and are just more street friendly.
Silver Surfer said:Here are the numbers from Desktop Dyno 2003. There was not a supplied file for this cam, nor does it seem that Lunati publishes their valve timings like Comp Cams does. I figure this cam is pretty comparable to the Comp Camps XE268 cam so I started with that and edited the few known values that are published for this cam.
You are looking at
365 HP @ 5,000 RPM
425 ft/lbs @ 4,000 RPM
Now about the cam, I see that the lift numbers are a little bigger on the Lunati and that the adv and .050 duration is larger on the Crane. But in comparing those 2, what set the Crane one above the Lunati to you? Just curious.I would also recomend you jump to a slightly larger cam
If it's an '87+ block it should be a roller block. That would be a big plus.Hi everyone. I'm new to these forums, I hope I'm not out of place. I will be swapping a bigger engine into my 92 Firebird. I have a chevy 350( 1 piece RMS, non roller, I'm pretty sure 87-up) block, making it a 383 stroker.
They will have to clearance the sides for the stroker crankshaft. Down by the oil pan gasket.I have all the stock parts that came off of it, but don't plan on using any of the parts I pulled off. When I take the block to be cleaned and all, I'm going to have them bore it to 4.030" and hone it out. I'm trying to get 400 hp out of this build. I plan on hooking up a T56 6spd and 3.73 posi rear to this engine. I've been talking to some people about parts to buy, but would like to get some second opinions and more help.
Iron heads will be cheap, but Vortec heads flow roughly 220cfm give or take a little, and will be adequate for a 383cube engine. I would put an aluminum head with a minimum of 195cc port that flows minimum of 250cfm. Something like this will do:Right now, I have a lunati 60103 cam and the lifters that cam with the 60103LK kit and a holley 4150 double pumper 650 cfm mechanical secondary carb. But I'm still figuring the rest of my build.
What I plan on getting:
Heads: Modified vortechs, assembled to handle .600 lift. 64 cc Scoggin Dickey Parts Center SD8060RA2 - SB Chevrolet Vortec Cylinder Head w/ 0.600 Springs for Roller Cams | SDParts - 1-800-456-0211
Excellent intake, can't go wrong with that.Intake: Edelbrock performer rpm air gap Edelbrock 7516 - Edelbrock Performer RPM Air-Gap Intake Manifolds - Overview - SummitRacing.com
It's better to buy everything as one package to save a few bucks. Try ohiocrank.com to see what packages they offer. Their cranks are made in the USA.Pistons: Probe 12344-030 forged dish, compression dist 1.425", +20.40cc Probe Pistons 12344-030 - Probe SRS Forged Pistons - Overview - SummitRacing.com
Connect rods: SCAT 5.7" i-beam rods SCAT Engine Components 25700P - Scat Pro Stock I-Beam Connecting Rods - Overview - SummitRacing.com
Crankshaft: SCAT 9000 series, 3.750" stroke SCAT Engine Components 935050L - Scat Series 9000 Cast Pro Comp Stroker Lightweight Crankshafts - Overview - SummitRacing.com
With an aluminum head you can go much higher on the compression than that and sacrifice virtually nothing. I run 11.77-1 and run pump 93. It will run on 91 octane but I don't push it when I run it on that. Personally I would shoot for 10.5-1 to play it safe and still make power.I also plan on zero decking this, getting a CR of 9.45:1 with head gasket thickness of .040". Just wanted to get as many opinions and/or advice as I could.
That cam is very mild for a 383. Your hp goals are very low and I'm sure you'd probably hit them or be close with the parts you pick, but next year you may want more power. Just trying to save you on a teardown for next year!
350hp will grenade a factory 7.5" rearend. 400hp that he is shooting for will pop it in a second. He will need a new driveshaft as well, then the flimsy factory stamped-steel torque arm will have to go, not to mention the stamped lower control arms.@ Joelster,
many 87' and up sbc blocks were roller but most trucks still came with a hyd flat tappet cam until 92-93' when they started making the first vortec sbc's. they were the ones with the swirl port heads, not the 906/062 vortecs that we all know today.
then you go into telling him to go after building a motor that will be pushing out 450-470hp which his 92' firebird wont hold up to very well. the 400hp goal he has is pretty much right where he wants to be unless he wants to start spending big $$$$ on setting the car up to handle it.
I have owned 6 Z-28's ('79, '80, '87 IROC, '91 G92 350, '94, and '95), so you aren't telling me anything I don't already know. My current Z-28 runs 10.5's on pump gas, in street trim. I know all of the weak links in a 3rd and 4th gen. 400hp will find them too.take a look at my profile name, My87z, and ask me how i know. that Z doesn't stand for and old datsun or nissan, it stands for Z-28. my most recent build has me running very low 11.0-11.15" and trust me when you exclude the motor i still have well over 10,000 into the car (not including the purchase price)
So how much of a difference would I see in the Howards cam vs the Lunati one I posted? I already have the Lunati, got it for a great deal from another guy. I can always just sell it to someone else and get another cam if it would be that big of a difference though.i had to go back and look at both cams to see why i would have recomended the crane cam over the lunati cam. I'm actually a bit suprised that i recomended a crane cam, there is nothing wrong with them they are of a very good quality i just dont look at them very often, i think i picked it solely due to it's profile.
the crane cam has a bit more duration which the 385 will like, the lunati has a tad bit more lift but that isn't enough to be felt. the reason i picked the crane cam is because it's ramp rates are a lot more friendly on a hyd flat tappet valvetrain then the lunati cam's ramp rate. your ramp rate in laymens terms is the difference in duration @ .050 and the advertised duration.
ex. crane cam: 234°-296° which is a difference of 62°, this is basically how fast the valve opens and closes.
lunati cam: 227°-268° which is a defference of 41°, this means that on the lunati cam the valve will be opening and closing (.000"-.489"-.000") in 2/3rds the time of the crane cam. 41° difference is absically what you will see on a solid flat tappet cam and is VERY aggressive. which an aggressive ramp rate means extra stress on the rest of the valvetrain.
now the crane cam acutally has more of a slow ramp rate, 62° is a good bit. if i were to build another hyd flat tappet 383 then i would look for a ramp rate in the 50° range. here are a few that i like a bit better than the crane cam, and i certainly like them better than the lunati cam.
COMP Cams 12-212-2 - COMP Cams Magnum Hydraulic Camshafts - Overview - SummitRacing.com
Lunati 00010 - Lunati Hydraulic Flat Tappet Camshafts - Overview - SummitRacing.com
this one would probably be my choice, i am a big fan of howards valvetrain products, i have been using them for quite a while with absolutly no problems and their customer service is second to none.
Howards Cams 112141-10 - Howards Cams Hydraulic Flat Tappet Camshafts - Overview - SummitRacing.com
and as i mentioned before, i wouldn't go with the scoggin dicky vortec heads for 800.00 when the 180cc RHS pro action heads are the same price and are proven to flow better and flat out perform better.
the Eagle kit you chose is just fine, i've used the 4.030" kit before and it worked great for me. if you match the howards cam, a nice performer rpm intake, a simple holley 750 vac sec carb, cheap HEI distributor (60K volt), with those RHS heads, and a decent set of headers and exhaust then you will be sitting in the 410-425hp rane but the kicker will be the 440-460tq you will make, all while using pump gas.
Yes. I knew there are a bunch of clearance issues with strokers. I had an idea that there could be cam clearance problems as well. Thanks for reminding me of that. I'll have to keep that in mind.On the stroker's cam profile is important! whether the lift is produced with a low heal (the lowest part of the lobe) or a high toe (the highest part of the lobe) The reason for this is because the rod caps come into close proximity (on longer stroke cranks) with the cam lobes and even hit the lobes on high lift cams and machining is necessary to achieve clearances sometimes negating the use of larger cams! You probably already know this and researched it! But sometimes cams are suggested because of this reason! So I thought Id mention it!:thumbup: In case you didn't know!
Jester
Not sure where you get this 7.625" information, but both of my LT1 cars came with a 7.5". EVERY LS1 car came with a 7.5 as well. I'm guessing that you are thinking of the oddball Borg-Warner rear that came in a few 3rd gens. Either way both are weak. Possibly with street tires, they will last a long time, but NO WAY at the track or street with a decent drag radial or a sticky DOT tire. Not a chance in hell. My friend grenaded his 10-bolt with a bone-stock LT1 car with a t56 and a set of BFG drag radials.his 92' already has the stronger 7.625" rear in it with the 28 spline axles instead of the 7.5" with the 26 spline axles. you are right about the TQ arm and the control arms. before i started drag racing my current set up i had a 355 putting out about 390-400hp, I upgraded to a 7.625 rearend from a 91' and I never had any issues with it.
think about this, how many LT1 and LS1 camaro's are out there with a set of headers and exhaust, reprogramed, with an aftermarket intake and just some other bolt on mods. these cars are making about 400hp and still using the same 7.625" rearend. dont get me wrong these rearends are week and will likely be the weakest link on the car with 400+hp/tq but i've seen plenty handle this kind of power without any problems.
They usually snap the teeth off of the ring gear and/or pinion gear when they go. People put a TA Performance girdle on them hoping they will get some life but that is money down the drain.its the 7.5" rearend with the 26 spline axles which is so much weaker. after saying all this, i must say that with my old set up on my 385, my 7.625" rear didn't last 3 weeks. but it was also putting out 490tq.
The cooling of the engine is a benefit but the main thing is the ability to up the compression ratio and not detonate. That is something that is FREE that cannot be ignored. Put an iron head on a 383 and run it at 11.5-1 and try to run pump gas. You will have to tune it pig rich and take timing out.I am someone who believes saving the money and doing it right the first time so i understand what you are telling him. I just dont think that is what he looking for. for many people 400hp in a street car is all they will ever care to have. based on the parts OP picked, i assumed that he was on a budget that is why i suggested the iron RHS 180 heads, and believe it or not they actually flow 258cfm @ .500", these numbers came from an independant shop that has flow tested hundreds of different heads on their SF600. most $1000-1250.00 alm heads are right in that range with them so how much would that extra $200-450.00 extra for the alm heads acutally benifit him. they are lighter, but if he's not racing then the extra 50lbs will never be seen nor felt. now for the heating aspect. the alm heads will be easier to cool, but as long as he has a decent electric fan he wont have any problems with the irons heads, on my previous motor set up i used Dart 200cc platinum iron heads and i never had any issues with keeping the motor under 190°.
I could piece something together for not much more $$$ and make it much more enjoyable. IMHO vortec heads do not belong on anything over 355 cubes. They simply don't have the ability to feed it correctly. A 355 with a head flowing over 250 will crap all over a 383 on vortec heads. It would cost a lot less too being able to keep the rods, and crank and not needing as much machining. He's going to run a 650 dbl pumper which can support 450+hp, and an Edelbrock Performer RPM intake which can go well over 500hp, and then crutch the build with some tiny heads trying to feed 383 cubes.Yes, would a set of AFR 195's, Brodix IK200's, or Dart pro-1 200's along with a hyd roller cam be his best option for making more power, absolutley. with these he would likely make 50-75 more hp all day but he would also spend another $1500.00 doing it.
Sometimes you have to make recomendations based on what you believe the OP wants, not what you would want. :thumbup: