Hi all,

First post here been lurking for about a year, this is a great resource thanks to you guys!

I am in process of building a 383 with a TPI and am looking for some opnions. The block assembly is complete but I have not placed the intake as I was hoping for some help verifying the cam choice that has been installed. I have purcased all chip buring hardware and hope to begin testing soon.

Thanks,
Rich

Build Details,
383 9.4:1 CR
World Heads (ported to 260 CFM in, 214 CFM ex @.500)
1.5 Roller rockers
Cam non roller hyd
Lift 468in/480ex
Duration 222/231@.50
LS 110
ILC 106
ELC 114
Speed Density
25# SLP injectors
SLP Runners (Still in the hunt)
Ported base and Plenum

 

Sounds good, but I think that cam is way to small for a 383. I would go with something with at least .500 lift but all the othe specs are reall good. Also maybe think about a HSR? Probably dont want to do it but it would be really cheap and benift that 383 SO MUCH MORE than a LTR set-up...and also think about gettin a bigger throttle body 52mm or 58mm. Sounds like ur on the right track for a stout motor though...post some numbers when ur done

 

Sounds good to me, I'd look at a bigger cam though.

Here's my 383 buildup....

10:1 Compression
Eagle 4340 forged crank
Eagle H-beam forged rods
Weisco Flat top pistons
All balanced
ARP bolts
ARP main studs
AFR 195 heads
LT4 Hotcam (.525"/.525", 218/228 @ .50, 112 LSA)
GMPP 1.6rr
TPiS Miniram
BBK 52mm tb
SVO 24lbs injectors
MSD Pro Billet Distributor
MSD 6a
MSD Coil
MSD 8.5mm wires
TPiS Prom (temporary)

Hoping she goes like hell!!

 

Unless you have to go though emissions, I would go with a HSR & a bigger cam, Comp XR276 or the next bigger one. I am running the 276 & intend to upgrade to a bigger solid roller next.

 

CmdrRiker,

Which World heads do you have and who ported them? I'm in Lemont IL and am curious as I have World S/Rs for a ~10:1 383 (S/Rs on a 383 desperately need porting) & I may not want to do them myself.

thanks number one

 

If you can afford it, you can pickup a new hotcam package from GM for ~$500. I think you'll be a little disappointed with that engine if you stick with that cam, unless you are just looking for a faster car.

 

I've got my 383 waiting to be installed right now, so I guess I'm not expert on them. But here's some of the info I've learned and been told so far during my build up process.....

First, if you're using fuel injection, which you obviously are if you're even considering SLP runners (duh!), your LCA may be a little off for the O2 sensor to work worth a tinkers u-know-what. Everything and everyone I talked to, including CompCams' gurus, said you want a minimum of 112 LCA. Mild setups typically go with 114LCA. I went with CompCams custom grind recommendation for my speed density 400+ HP / 500+ ft-lb 383. They recommended an LCA of 112 with an installed intake centerline of 108. Granted I'm running a little more compression than you (maybe too much for the iron Sportsman IIs I've got) at 10.5 and I don't know if that will matter or not. I'm also running 495/500 lifts if you use 1.5 rockers but at 218I/224E durations (I've got 1.6's on the intake side). That's what they recommended to me anyway, and since they're the experts and no one would contradict them, that's what I've got in mine. It's also real close to the LT4 HotCam like speed88 is using (and lot's of others as I'm sure you know).

As far as an intake set-up, I also went with an LPE SuperRam on mine using 24 lb injectors (which may have to be increased) and AFPR. I considered the StealthRam, but since I've got to look like I'm trying to pass an emissions visual inspection I went with an emissions compliant intake (which the SuperRam is and the StealthRam is not). I'm also using a BBK 58mm throttle body on it but I also have a Holley 52mm in reserve if it doesn't work out. I'm also running the SLP Tri-Y headers on my rig (with AIR). I went with the SuperRam because I wanted the extra flow so it wouldn't choke out at 4500 RPM, but I also didn't want to give up the in-town level of performance that the Stealth requires you to do to get their gains on the upper end. I just don't run over 5500 RPM all that much, ya know? Torque is king on the streets, so I went with the SuperRam as a slight compromise/best of both worlds to keep the TQ up without hurting the HP too much. I also had ACS ceramic coat everything - headers, Y-pipe for the dual cats, SuperRam plenum and runners. Figured every little bit helps on the temp side of things but I probably went a little overboard (but I like the way it looks!!!)

Sorry to be so long winded on this. Hopefully some of of this info will be useful. If not, sorry for wasting so much of your time with such a long post. Have a Great Day!!!

--- Vern

 

I hate to say it but the Hot Cam is mild in a 383 I have it.The only reason I used it was to pass emissions.My 383 with the Hot Cam idles like my stock 350 did with a CompCam dur/210*-220* Lift/.480-.480 LSA/112 that was also mild.I will say that if you do alot of street driving it will be good it has very good throttle response and torque.My next cam will be in the 230*-240* range.

 

I thought the hotcam was going to be a little mild for a 383. But I had bought the hotcam for a 350 build-up which turned into a complete rebuild, and then changed to a 383 instead. So I'm kinda stuck with the cam now because I would like to get some use for my money from it.

 

If you want to keep TPI and a flat-tappet cam, I dont think your cam choice is as far off as these guys say. The TPI isnt going to make much power beyond 4K, so running a cam with a RPM range above that will just bleed off cylinder pressure where the TPI is working best. Youre also running under 9.5:1 static CR, so anything bigger than the duration you listed may drop the dynamic CR lower than what you want. The LSA does seem a bit narrow, though, Id look for something in the 112 deg. range. The lift seems ok, you cant get too much lift out of a small duration flat tappet, but you may want to change to 1.6 rockers, though. Id also suggest 1 5/8 longtubes, then a set of drag radials and suspension mods, you are going to get zero traction.

Also, if you are going to go through the hassle of a hyd. roller conversion, there are many better cams out there than the damn Hotcam, look into Comps XE series.

 

Guess I should have mentioned that my cam specs up above are for a hydraulic roller cam.... Sorry!



.--- Vern

 

Thanks to all that have replied. Since some time has elapsed from the post being brought back to life, I have installed the cam and would like to continue the build.

It appears that the general consensus that to 110 LSA is going to be a problem. Any other opinions as to the need to remove the cam before I install the engine. Keep in mind that this will be for a daily driver.

Thanks,
Rich

P.S. 377Z I will send you a note on the heads and porting.

 

I did the 383 Trick Flow Heads. 219/219 560/560 112 cam and a Superram. I wouldnt go less then 112 as mentioned above. I've having a little vacume problems as it is. Good Luck

 

Just finishing up with my 383, I am running LTR with edelbrock runners-aluminum heads ported 205.0 intakes, coating on piston and combustion chambers comp cam on custom grind LSA 112. 11:1 compression msd 6al 24lb injectors and all the smog gear. 700r4 with 2500 stall. It has a lot of torgue. I am running MAF and still have not messed with the chip yet. My best run was 13.5@104 mph, with best 60@2.62, I think if I can get it to hook up I can get 12"s. Sure is a fun street machine.
here is pic of heads. I still am running the 48mm throttle body, thinking to going to 52mm

 

Here a pic engine showing runners

 

it really sounds like everyone is goin with the 383s im tryin to decide what i want to do sounds like that is the way to go. but im tryin to decide to either go with the hsr or superam what do u guys think? thanks brycon

 

Granted this is just my two cents on this, but I think you'll find it matches other info (do a search on both and plan to spend a few hours reading thru everything like I did).

Basically, it looks to me like the answer boils down to how you plan to use it. If you're looking for a drag race car (on a strip) where you want the maximum HP output you can get at high (redline area) RPMs, then the HSR will probably better suit your needs.

If you are looking at primarily a street car, where you want more low end performance (which is primarily TQ based), then you'll probably be a lot happier with the SuperRam.

I decided to go with the SR. If I ever make it to the strip, it will primarily just to see how it does. I'm not into recognized organized drag racing from a participant's perspective. To me street performance is a lot more important. I like "spanking" the occasional ***** and Mustang (whoopee!), and to make a statement with a tire burn every now and then.

Since the HSR gives up a lot of the low end performance (the stuff you'll actually be using on the street) to get the high RPM end performance, I opted for the higher low end performance of the SR. But if you're looking for an organized drag competition race kind of car the HSR sounds like the hot ticket now days (a lot of "bang for the buck"), or possibly one of the LT1 set-ups.

 

Properly matched with a 2500-2800 stall and 3.45+ gears, an HSR has enough low RPM torque to overcome any street tire. The SR may make more off-idle/low end, but theres a point of diminishing returns when it comes to low end torque and street tires. It depends on preference, but personally I believe a good street car should have a broad torque curve, not necessarily all low end. ....unless your goal is to just smoke the tires for blocks or tow things...

 

I agree with formularpm how much low RPM torque do you want/need with street tires?Even with B.F. drag radials I can smoke them up if I want.

 

Yep, thats the beauty of having a V8. You dont have to have long runners or short cams to make decent low-RPM torque.

 

well im planning on goin with a 383 and i want to turbo it so i dont really have to worry about the top end i just dont really know if i should go with afr 210cc or i want to maybe go with world sportsman2 heads and get them ported. im still lookin around and reading but i thought i could maybe get some anwsers on here and hear what u guys had to say. thanks brycon

 

wondering if you guys with 383's can post some time slips. also what throttle body are you running?

 

I dont have any time slips yet with the 383 it has a couple of gremlins still.But when I switched from long tube TPI to the stealth ram On my old 350 I droped .3/sec. consistently.

 

can any of you guys tell me if i will benefit very much with going to a 383 vs my new 355 with my mods? i like my ltr setup and dont have the money right now for the hsr. .....thanks

 

they say there is no subsitute for cubic inches. i always think bigger is better

 

Stuart,

Cubes are great, the more the merrier. But costwise, if its either HSR OR to go from 355=>383, then the HSR will be cheaper--to go 383 you will need at minimum:

3.75 stroke crank
pistons -OR- rods+balancer+flywheel
get it all balanced

All this would add up to over $550 or so for the HSR (plus all the extra work if your 355 is already assembled). But if I misunderstand the situation, definitely go for the extra cubes if you can--I would (and did).

Just my opinion--hope it helps.

 

377z, to go with the hsr i will have to change heads because of the vortec design. thats why i was asking if the extra 33 cubic inches would be a lot of difference over my 355. i wish now i had went with the 383 because i find myself wondering (what if). dont get me wrong my setup that i have now will scream, but if it would be a big difference i on the 383 thats what i wanna do. i have access to a crank, rods and machine shop. all i have to get would be my pistons right? i can reuse my new flywheel and balancer as long as its all balanced together right?

 

Sorry, I overlooked the vortec heads issue.

Personally, I would go for the extra cubes if I could--looks like you have some nice parts. Will it be a big difference? I don't know, the "what if" question is exactly why I went with the longer stroke. You can use your balancer and flywheel if you use 5.7 or longer rods (this way it can be internally balanced)--so if you have the crank all you'd have to buy are 383 pistons, then get everything re-balanced. The other way is to use 5.565 rods & your 350 pistons, but you have to get a balancer & flywheel for a 400. If I were in your position I'd use 5.7 rods (heck you already have them) & buy pistons since #1: you already have a balancer & flywheel, & #2: you can choose an appropriate compression ratio for what you want to do (going to a 383 using the pistons intended to arrive at a specific compression ratio for a 355 may yield a too-high ratio with the 383). Either way, you'll still need to clearance the block and make sure your rod bolts don't hit the cam. Otherwise, I think thats everything.

Good luck either way