I finally got my 383 home guys with big cams in here

Ok I got the bottem end of my 383 home YAY! :D

Specs:

Scat 9000 cast steel crank
Scat 4340 I beam rods
KB Hyper flat top pistons

Now I want a cam I`ve talked to 2 builders and they said anything over .510 lift will not fit:( The valves will hit the pistons
Well the pistons have big valve releifes in them and every mag I reads never usees anything that small it`s always over .520 lift

so I`m I stuck with a .500 lift or smaller?:confused:

where did u buy the kit from? i would call them/email them or somethin about how big a cam u can run w/ the setup u have there. from the sound of things and the pistons having big vavle relief's i dont see a prob. going w/ a nice cam.

just remember to try and match the cam,heads,and intake together to have ur motor run how ur gonna want it to run.

why dont you just check the valve clearance and see how much you have, better to know for sure in your engine than depend on someone else's specs :rolleyes: .


Chad

Originally posted by coony278
why dont you just check the valve clearance and see how much you have, better to know for sure in your engine than depend on someone else's specs :rolleyes: .


Chad

Because I do not have heads or a cam :rolleyes:

you can not check without those:rolleyes:

:bs: :bs:
I don't know who's telling you this, but how can they know??
Are your pistons really domed or something??
What cc heads were recommended to give you the compression ratio you bought, with your pistons??
The 383 pistons' pin location is raised so the piston fits the same location in the bore as the 350, so if the cam would work with a 350, it'll work with your 383...:irk:

There is NO WAY to know that without actually mocking up the assembly, putting some clay on the top of the pistons and turning the engine over by had.

Valve-to-piston interferece does NOT HAPPEN AT MAXIMUM VALVE LIFT. By the time you're at maximum lift the piston is half way down it's bore- almost 2 an inches down from the valves! NO WAY you'll ever hit at max lift. Think about it.

Valve to piston interference happens during the OVERLAP period between the exhaust and intake strokes. Both valves are open slightly as the piston approaches TDC. The cam's duration, lobe separation angle and lobe profiles have a LOT more to do with whether you will have interferece during this period than maximum lift ever will. WAY too much stuff to just look at cam specs and say "this one will hit" or "this one will clear." You MUST do the clay test I outlined above if you want the real answer.

Or you can skip it and hope for the best. But how may times do you really want to do this job?

Originally posted by Damon
There is NO WAY to know that without actually mocking up the assembly, putting some clay on the top of the pistons and turning the engine over by had.

Valve-to-piston interferece does NOT HAPPEN AT MAXIMUM VALVE LIFT. By the time you're at maximum lift the piston is half way down it's bore- almost 2 an inches down from the valves! NO WAY you'll ever hit at max lift. Think about it.

Valve to piston interference happens during the OVERLAP period between the exhaust and intake strokes. Both valves are open slightly as the piston approaches TDC. The cam's duration, lobe separation angle and lobe profiles have a LOT more to do with whether you will have interferece during this period than maximum lift ever will. WAY too much stuff to just look at cam specs and say "this one will hit" or "this one will clear." You MUST do the clay test I outlined above if you want the real answer.

Or you can skip it and hope for the best. But how may times do you really want to do this job?

Well with the clay test you have to buy the cam and if it don`t work your suck with a cam you can`t use thats the only bad part. I have a compcam it`s a 285S the lift is .540 I think I`ll have to look up specs, if that cam works I can go from there. I won`t use that cam because it`s just TOO big and I won`t get vacuum and power won`t come in till 3500rpm

I forgot to ask if he zero decked the block that will make a difference

And say you have 10:1 pistions will they crack if you run 11:1 cr?
I want to run the vortec L31 heads or maybe the 195 AFR`s and I was thinking a soild cam with .520 lift I`ll have to E-mail comp to see what they`ed run with my setup.

This is what I`m thinking so far

383 with flat tops
L31 Vortec heads with valve guide work
Holley stealth for vortec heads
Thats the basics so far thanx for the help :D

well unfortunately the HSR will not fit with 96-up vortec heads. they are raised port and only have 8 intake bolts holes at a 72* angle. not 90*. visit www.stealthram.com

My bad I meant Weiand stealth 4 bbl intake but if they don`t have one to fit the vortecs then I`ll find anther intake

Damons right, clay test if you run a tight LSA angle or bigger duration. With most of the EFI cams running smaller durations and wider LSA's, overlap's not really a problem.
But you will have to check your "valve seal to retainer" clearances, and valvesprings installed height. Or your springs could bind(compress solid) or the retainer might hit the seal, bending pushrods..
But I do use clay on my motors, I don't like taking chances either; like the "Double Hump", Crane MC Cam motor I just built for a '72 Monte Carlo...Just about finninshed on the install, should have it running next week. This ones gonna be "lumpy"!...:cool:
(He even found an Old Mr.Gasket "clear"distributor cap...and Zinc'd brkts/pulleys.)

These are the 2 cams I`m looking at

XS274S and XS282S

There both Compcams Xtreme energy cams

Specs

for 274S 282S

dur at .050

.236 .240 .244 .252

lift

.501 .510 .520 .540

110 LSA 110 LSA

I`m looking for alright power up top but want more down low what is the idle like on these cams? I want it to sound mean:bow:

Those cams will definately give you a mean idle, especially since they are solid lifter cams. Definately invest in a good set of poly locks unless you really like adjusting valves.

The XE's are definitelty agressive, the overlap, unlike a Crane Compu cam with the same LSA which is still designed to give about 17"HG @idle, CC is choppier.
The one thing to ask about is how much vacuum at idle the cam will make, granted a large cam for a 350 is mild in a 383...

I'd go with the 274*, b/c it doesn't give up much lift, and just a little duration, BUT its manners should be much better and should almost make the same power, and easier on parts...:think:
I crunched these 2 cam specs for my own 383 wish list a few times...

I've got a comp cams 230 244/510 540 in my 383...

amc,
Why are you only running a 12.41 @ 113 with a 100 shot? And why the 22pph injectors? I would think NA 12.41 no?

amarillo's track SUCKS!!!!!!!!!!!!!!! I had this engine in an 89 IROC and it ran ALOT stronger b/c of the mass air...now its in a speed density car and I'm sure it needs better tuning...a friend and I burned a chip for it so it runs and thats about it. Just havent bought bigger inj. yet...all comes down to money...

Originally posted by amc91z
amarillo's track SUCKS!!!!!!!!!!!!!!! I had this engine in an 89 IROC and it ran ALOT stronger b/c of the mass air...now its in a speed density car and I'm sure it needs better tuning...a friend and I burned a chip for it so it runs and thats about it. Just havent bought bigger inj. yet...all comes down to money...

WOW, you are missing some power! Sucks about the programming issue. I would think youd run mid 12s with no spray!:confused: :confused:

Hey amc91Z what kind of comp cam is it. is it a roller or flat tappet. that is the size of cam I wanted in the 1st place. Man i never thought picking out parts was going to be this hard:(

Hey heavychevy what size of cam do you have in your 383? and what are those dart pro 1 heads like?

Originally posted by Chris`s85Z28
Hey heavychevy what size of cam do you have in your 383? and what are those dart pro 1 heads like?

Well, the cam that is in there NOW is too small and I don't know exactly what it is cause the engine was built by an out of state builder and I never had to go inside it yet. Once my car wasn't puttin up the #s I was expecting, I found out that the cam is not what was supposed to be in there. It is something around 230ish duration and the engine is supposed to have a cam around 250 @ 050 w/ around 550 lift. With this mismatched cam, the car ran 13.1 @ 105. The Pro1 heads are really nice. They are a direct replacement for a stock head and flow alot of air. I have the 200cc version and they are pocket ported and the runners are cleaned up and they also have undercut valves. I feel they are not performing to their peak because of the cam. Once I R/R the cam with a CC XS282S, I am expecting a nice bump in power. Check sig...

Hey the XS282S is what I want I`ll look in to those Dart pro1 heads I noticed your 383 is forged mine isn`t:( I have hyper KB pistons you know the ones between cast and forged at the time I thought theyed be great since there better then cast and lighter then forged boy was I wrong:( :( :mad:. what intake are you running I want to run the Stealth Dual plane with a 750 Dubble pumper

My goal is 400-450 hp and mid to high 12 sec 1/4s

But I need a cam with vacuum since I`m running power brakes

Originally posted by Chris`s85Z28
Hey the XS282S is what I want I`ll look in to those Dart pro1 heads I noticed your 383 is forged mine isn`t:( I have hyper KB pistons you know the ones between cast and forged at the time I thought theyed be great since there better then cast and lighter then forged boy was I wrong:( :( :mad:. what intake are you running I want to run the Stealth Dual plane with a 750 Dubble pumper

My goal is 400-450 hp and mid to high 12 sec 1/4s

But I need a cam with vacuum since I`m running power brakes

I am using a Team G that has been port matched and cleaned up a bit. It is a single plane. If you are going to use the XS282S then I would recommend a single plane not a dual plane because the cam isn't gonna kick in till 2800 rpms and the single planes are for rpms between 3000 and up. You won't gain that much low end by using the dual plane. PLUS if your stall is 2800-3500 then your just gonna shoot right past the low end when you nail it anyways.

you need to get your heads before you can actually tell how much valve to piston clearance youll have. plus if you want to run a dual plane instead of a single plane holley makes a dual plane for idle to 7200 rpms its jegs part # 510-300-36. it should work fine for a 383 unless you plan on running past 7200 rpms which isnt done in just about any motor very often unless its rebuilt every 500 miles.

Originally posted by xeroxed
you need to get your heads before you can actually tell how much valve to piston clearance youll have. plus if you want to run a dual plane instead of a single plane holley makes a dual plane for idle to 7200 rpms its jegs part # 510-300-36. it should work fine for a 383 unless you plan on running past 7200 rpms which isnt done in just about any motor very often unless its rebuilt every 500 miles.

I didn't know this. It's nice to know these things...
Has anyone compared this new manifold with other proven models?

theres a couple guys at a 2nd gen site i go to that have tried that intake and love it. i'll probably buy one for the 350 im building.

Originally posted by xeroxed
theres a couple guys at a 2nd gen site i go to that have tried that intake and love it. i'll probably buy one for the 350 im building.
that's great and all but I would like to see actually dyno #'s that show the power production results of different manifolds compared to it. Maybe a magazine has done it or will do it.

Man HevyChevySS you have the engine I want I was thinking of the team G too but I thought of the weiand Steath because it`s a dual plane that goes from 0-6800 RPM I thought it would be better for a street car But the team G is what I really want or the Xcalliber

My dream setup is:

383ci With AFR 195`s a XS282S and the TeamG with a 750 Dubble pumper

Maybe I should take my 383 apart and put some TRW forged pistons in but than I need to balince it because parts will be mismached:( :confused:

Oh and I don`t plan on reving past 6500 rpm if that

It took me months before I found the right combo of parts for my engine. The Pro1 heads are nice and the AFRs are also in the same league. Damon has a set on his 383 and he loves them. If I had to build another 383, I wouldn't mind going with the AFRs.
About your pistons...if your not going to spray then don't worry about it but if you are then I would not take any chances and go the extra route and get the forged slugs in there now. I don't think a machinist would charge that much to balance everything again for you.

Good luck with it.

I know I`m not going to spray it I think NOS is cheating I want my power to be all motor no power adders

Well I think I`ll go with the Pro1 heads there $1795 pair and the AFR 195 heads are $2400 pair and th AFR`s don`t flow that much more. and the team G intake is $289 the XS282S is about $300 with lifters and a DF DP 750 Holley is about $500-$600 That should be good for 400+hp and 12 sec 1/4`s
:bow: :D

$1795 seems kinda high, Summit has them for under $1300 I think. Which ones were you actually looking at?
Check out this site... http://www.dartheads.com/csbhpro1.htm

I have the babies of the bunch...200cc, 2.02/1.60, 72cc and they do a really nice job. I actually asked the engine builder for the 215cc model w/ 2.05/1.60 setup but got shafted and didn't get them. But I am happy with my set. They blow away any other non aluminium head out there! IMO

And about your 1/4 time predictions.... I dynoed my currently mismatched engine combo on a chassis dyno and had 310 RWHP and I ran 13.1 @ 105 mph. So if you end up with 400-450 HP; doen't be surprised if you are running lower 12s than you think ! :thumb: :thumb: :thumb:

All prices are canadian since I`m canadian so belive me $1795 is cheap another shop wants $1800 for the Iron Eagle and the Performer RPM heads are $2800 :eek: :eek:

so as you can see 1795 for the Pro1`s are good

I`m looking at the 64cc heads though because I want atleast 10:1 cr

But I bought the GM performance parts book and I thinking about the Fast burn heads

GMPP fast burn`s:

64cc chambers
210 cc runners
raised ports
early intake bolt and Vortec style
2.00"/ 1.55" valves

I`m going to find out what they cost tomarrow with there single plane eliminator intake

fast burns are nice....but the valves are smaller. Youll have more torque less HP....but they are a proven power maker!

I ran a combo a few years back with small valves...1.94/1.50 with horrible flow #'s, like 259@.600/168@.600, 11.9:1, pump gas, small cam, 224/234 .534/.561 on a 114 LS, Hooker 1-3/4" LT's, most bolt-ons, 3.73, 3500 tq..in a 3600 lb car on BFG DR's.

With little tuning ran 11.7's@116 with major internal engine problems(that I did not know until I tore it apart).

Lot to be said small cams and poor flowing heads...sometimes they surprise ya.

I`m a dumbass I forgot to price the fast burns today I hope I rember tomorrow. I`m really leaning to the fast burns now I looked at a page thats linked in "the true duals ?" The guy wants the same dual setup I want and theres a link someone put in his question that has a guys 86 Z28 that he built and his engine has the Fast burns on a 350 with the LT4 hot cam and Victor intake and ran 11.7 in the 1/4 :eek: so if I get in the 12.3X`s I`ll be very happy and another cool thing is he has the hyper pistons in the 350 like me and they handled that kind of power:D

I hope the fast burns arn`t much more than the pro1s

I priced out the fastburns and there 1395 each YES EACH:eek: :eek: and the intake was 500:eek: so the pro1`s with a team G is what I`m going with:D Thanx Heavy Chevy SS for the help good luck getting your Chevelle SS in the 12.XX`s

I paid $525+tax each for the GMPP FBs from Salle Chevrolet.

Originally posted by raul.garcia
I paid $525+tax each for the GMPP FBs from Salle Chevrolet.

He is in Canada so it's different for him.

Good luck with the Pro1s, you won't be disappointed.
There is a guy selling a set of Pro1s w/ a matched intake locally. They are the 230cc model with porting and intake was ported also. He only wants $2500 (american) for them. I think it is a good deal but you'll need a huge cam for this set up.

I feel my car will be running low 12s no problem, but it's gonna get tricky once i start using the spray.:D :D