: 383 tbi cam selection?


Camok5
01-03-2007, 06:07 PM
I'm trying to figure out what cam to run in my 383 tbi engine. I was told that the cam in it right now (comp cams xtreme 4x4 hydraulic cam) Doesnt have enough lobe separation at 111*. The engine is a pre 87 4 bolt main block that has a scat 383 kit and World sportman heads. I dont want to put a roller cam in because of cost and its going into my blazer that doesnt see much over 4000rpms. I plan on upgrading to a larger tbi, injectors, chip, etc. and smog is not an issue. Can anyone tell me if I can make this cam work or is there a better cam to run?

STACKED
01-03-2007, 06:34 PM
i was reading somewhere else that stock 94-95 stock lt1 cams work good. not sure about the specs but you might want to check it out.

BULLET99Z28
01-03-2007, 06:47 PM
The Lt1 cams are roller,won't work. And to the person who started this thread,you need to check this out-If you are familiar with the GenIII blocks(LS1),you know they have plastic lifter trays wich keep the lifters from rotating in their bores. Well Gm just released the same thing only for pre87 blocks. they are real cheap,and all you do is drill/tap a small hole on each side of the lifter valley to retain the lifter gloves. then you just use 87+chevy roller lifters,get a roller cam button(cheap)and put a hardened gear on your distributor(cheap). As far as the cam,call Comp,give em all the specs-runner size,valve size,combustion cc's,they will hook u up.

STACKED
01-03-2007, 06:53 PM
what you cant put a roller cam, lifters etc in a tbi motor

Camok5
01-03-2007, 07:46 PM
You can put a roller cam in a tbi motor but I have an older block that would have to modified to execpt it.

STACKED
01-03-2007, 09:11 PM
oh i gotcha

BULLET99Z28
01-03-2007, 09:14 PM
Yup,all TBI motors are roller cam from the factory,anything gm(v8 that is)86+ is roller cam. Pre 86 can be converted very easily by the methods i described above. I can get you guys some info if ya want

odee
01-04-2007, 04:59 AM
Bullet99z28 is it possible to get the part number for this new retainer by gm. The local dealer here if you dont have no vin number no help. I'm fixing to do two 383 swaps for friends and one in my sons new buggy that I'm putting tuned port on. I would really like to run a roller in all of them.

chewingum
01-04-2007, 05:21 AM
I would never put anything BUT a roller cam in an engine again, the cam profile selection you have with a roller is the main benifit. Sure they cost alot, but for good reason.

BULLET99Z28
01-04-2007, 03:10 PM
Bullet99z28 is it possible to get the part number for this new retainer by gm. The local dealer here if you dont have no vin number no help. I'm fixing to do two 383 swaps for friends and one in my sons new buggy that I'm putting tuned port on. I would really like to run a roller in all of them.

Yeah,I'll get you the info,I don't have my car mags dug out yet(just moved),but I'll go over to LS1tech,and post up. I think hot rod ran a small article this summer on these lifter gloves. I think they are less than 20 bucks,def read the info,just not sure on the magazine. GM perf.parts catalog and Comp cams should have the cam retainer info,you need either the retainer or cam button to keep the cam from moving around. the retainer is standard on the 87+ blocks. But the lifter gloves look almost identical to the gloves in the genIII motors. And no,roller cams aren't expensive at all these days,matter of fact,many cam companies are slowly fading away from flat tappet stuff. Much better quality control,better profiles-duration,better ramp rates,everything is better with the roller!!!

cj8scrambld
01-04-2007, 05:32 PM
Yup,all TBI motors are roller cam from the factory,anything gm(v8 that is)86+ is roller cam. Pre 86 can be converted very easily by the methods i described above. I can get you guys some info if ya want

Sorry, but not ALL TBI motors are roller equipped.

BULLET99Z28
01-04-2007, 07:22 PM
I thought Gm went exclusively with roller cams in the smallblocks,and 1 piece rear mains all at the same time.(86/87)And in 1988 when the pickups went with efi(TBI) those are all def. roller cam.All my gm car and truck service books read that way. Any way,the gloves I mentioned are for factory roller cam blocks only,and hold the lifters up out of the way so you can do cam swaps w/o removing the intake. But you can use the aftermarket roller lifters that are linked together to keep from rotating. And i believe you can run a roller cam(even 87+) with the right retaining plate. Just contact Comp,they have a good tech dept,or call Skoggy diggins(SDPC) they build motors and have a great catalog. they can def. help. i will do some more research.Its been a while since I've looked into this

reddman
01-04-2007, 08:46 PM
Sorry, but not ALL TBI motors are roller equipped.

Are TBI big blocks what you are refering to?

A good rule of thumb is if it came with centerbolt valve covers it is one piece rear and roller cam iirc. (well at least for small blocks, never spent much time around rat motors)

cj8scrambld
01-05-2007, 08:02 PM
No, Actually I was only referring to the SBC...they were not all rollers. They may have had roller provisions (the blocks set up for) but they did not all come with rollers from the factory.

Buckshot33
01-05-2007, 08:42 PM
all EFI chevy SBC's from 1990 forward are deffinately roller cam motors. 86-89 motors are hit and miss. I have pulled tbi 350's out of an 1989 sub and found it to be non roller. Most TPI motors were roller. after 86 all SBC's were 1 piece rear main but again, not all were roller motors till after 1990.

jmhinescj
01-05-2007, 10:50 PM
so...are you guys saying thaat all tbi motors 1990+ are setup for roller cams but may not have the actual roller cams and lifters...or are you saying that all of them came with roller cams and roller lifters...I'm pretty new to tbi motors but when I broke down the one I'm workin on now it was all flat tappet hydro lifters.
or are you takin about TPI motors?

cj8scrambld
01-06-2007, 08:32 AM
all EFI chevy SBC's from 1990 forward are deffinately roller cam motors. 86-89 motors are hit and miss. I have pulled tbi 350's out of an 1989 sub and found it to be non roller. Most TPI motors were roller. after 86 all SBC's were 1 piece rear main but again, not all were roller motors till after 1990.

My 1994 TBI 350 Blazer has a hyd flat tappet cam.....Oh, and I am the original owner. So what gives?

cj8scrambld
01-06-2007, 08:52 AM
so...are you guys saying thaat all tbi motors 1990+ are setup for roller cams but may not have the actual roller cams?

Yes, I am saying that they were SETUP for but not all have (actually few have) rollers in them....the SBC TBI motors from MOST trucks had flat tappets until '96 when the Vortec 5.7 arrived with the Vortec heads and roller cam.

EDIT: The Edelbrock TBI cam for the SBC TBI of all years up to and including '95 is flat tappet. They don't have a roller option, why would one take out a roller for a flat tappet?

Good info, read the part covering camshafts. http://www.tbichips.com/truckmods.htm A qoute from Brian's site " All 87+ cars got roller cams but the trucks didn't get one until 1996 (Vortec). The trucks have all the provisions for the roller equipment but just didn't get the parts."

botiejeep
01-07-2007, 03:10 PM
The last guy is correct. My 90 350 does not have a roller cam although it does have provisions for one.

reddman
01-07-2007, 05:56 PM
Fawk, learn somethin every day. :emb:

What about the early vortech 4.3's? I have already been thinking seriously about one for the buggy. I thought my 88 SB already had them, but if not thats just another reason to go 4.3

Hillbilly
01-07-2007, 07:29 PM
i don't know about the 4.3s reddman, i can tell you I've torn down SBs from 86 to 93 and haven't found a roller cam yet. Like what was said earlier the later model blocks had the provisions for roller setups, the 86 and 87 I tore apart most certainly didn't.