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Old 07-14-2007   #81
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

I was checking out some cams on the CNC Store where Munson found the Eagle Kits. I went through most of them but I'm having difficulty trying to decide which one would probably be best. Can someone give me some help please?

CNC Camshafts and Lifters

These are also the others that I'm looking at buying. These guys are probably going to love me when I place my order here soon. LOL! The only thing I wasn't sure about was the stud size for the rockers. They have both 3/8 and 7/16 stud sizes. I picked this one because it says thay work with the center bolt valve covers.

CNC Eagle 383 Stroker Kit
CNC 1.6 Aluminum Roller Rockers

Also, I had a buddy look at my heads yesterday and they are going to need some machining done to them. Any idea of what my combustion chambers are going to be after the work is done? Also if that is going to raise my compression, how can I bring it back down so that it isn't so high? Thanks for all of the help Cliff and Munson.
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-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-14-2007   #82
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

Quote:
Originally Posted by strc09
I was checking out some cams on the CNC Store where Munson found the Eagle Kits. I went through most of them but I'm having difficulty trying to decide which one would probably be best. Can someone give me some help please?

CNC Camshafts and Lifters

These are also the others that I'm looking at buying. These guys are probably going to love me when I place my order here soon. LOL! The only thing I wasn't sure about was the stud size for the rockers. They have both 3/8 and 7/16 stud sizes. I picked this one because it says thay work with the center bolt valve covers.

CNC Eagle 383 Stroker Kit
CNC 1.6 Aluminum Roller Rockers

Also, I had a buddy look at my heads yesterday and they are going to need some machining done to them. Any idea of what my combustion chambers are going to be after the work is done? Also if that is going to raise my compression, how can I bring it back down so that it isn't so high? Thanks for all of the help Cliff and Munson.

Ok, first I thought you were going to go with that other kit Munson was talkin about. Anywho, if this is the one thats fine, as for your compression, you are going to have to find that out after he does the work. Did he give you any idea on how much he was going to remove? Also, you can raise or lwr your compr with the head gaskets, and if you get a cam thats has a split duration( ie: 230 on the intake and 240 on the exhaust is considered a split duration). then that will help also as for lowering your compression while making plenty of pwr. Also the LSA(lobe speration angle) needs to be at least in the 112 to 114 area, IMO. If you go to Comp cams website, they have a fairly new cam that would work great in your application called the XFI cam and they are on a 113 LSA which would be ideal for your motor, of course you can always call up Comp and give them your application and get a custom grind cam. Oh and if you are usin 1.6 rr's when you start to assemble the motor you will need to check all of your clearences with some clay putty. hth
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Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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Old 07-14-2007   #83
FearThisGTA
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

oh and your rocker stud size should be 3/8.
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Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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Old 07-14-2007   #84
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Sorry Cliff. I should have given a PN when I made that post. My bad. I saw a few that had the 112-114 that you were talking about. What was confusing me is that some said rear axle ratio as well. What does that have to do with it? I want to upgrade, but I'm about to drop some serious change on just the motor alone and I can't really afford to change the gears right now. That'll come later (probably next year).
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-14-2007   #85
FearThisGTA
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

The gear ratio effects the rpm's hence the cam profile will need to fit that rpm range.
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Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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Old 07-14-2007   #86
MunsonGTA
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Posts: 1,948



GTA Year: 1987
GTA Engine: Custom
Re: 383

112 lsa would be fine for a street 383. i run a 112 in my car and it's a DD when it runs. i was actually considering going to a custom ground cam with a 110 lsa. like cliff said, you can use different size head gaskets to raise and lower compression. why did your buddy say the heads need work?

and as for those rockers, they look like a good product. i'd run self-aligning though. i'm pretty sure all vette heads were made to use them. i know i tried a set of non-aligning on my car and they didn't work right, even with my pushrod guides. i had a rocker literally come off the valve stem and ride the spring retainer. after i replaced those rockers with a set of self-aligning, i've never had another problem.
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87 GTA: Forged 408 LSX short block, TEA stage 2 cnc ported 243 heads, BTR Stage 3 stroker cam, Fast 102 intake, NW 102 TB, Longtube headers, custom 411 ECM, custom harness, custom tuned, Performabuilt stage 2 4l60E with PTC 2800 stall, 9 bolt rear with 3.70 gears and TAP girdle.

11.16 at 123 mph.
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Old 07-14-2007   #87
MunsonGTA
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GTA Year: 1987
GTA Engine: Custom
Re: 383

this would be a good article for you to read. it'll help you understand things a little better.

http://www.thirdgen.org/mods2
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87 GTA: Forged 408 LSX short block, TEA stage 2 cnc ported 243 heads, BTR Stage 3 stroker cam, Fast 102 intake, NW 102 TB, Longtube headers, custom 411 ECM, custom harness, custom tuned, Performabuilt stage 2 4l60E with PTC 2800 stall, 9 bolt rear with 3.70 gears and TAP girdle.

11.16 at 123 mph.
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Old 07-14-2007   #88
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Thanks for the info fellas.

The reason they still need a little work is because the bottom side of the heads around a couple of the cylinders have some gouges so they probably won't seat correctly. Nothing really deep so that's a good thing. Like Cliff mentioned previously just flattened.

I'll go back to that store and see if I can find a set of self aligning in that style. When you say didn't run right, why wouldn't the car run right? As for the rocker coming off...yeah, I had that happen to me before while I was cruising about 85 down I95 in my 66 LeMans. I thought my freakin' motor blew up on me. Lucky that's all it was because I was a ways from home and thet would have been an expensive tow bill. LOL!
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-16-2007   #89
MunsonGTA
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GTA Year: 1987
GTA Engine: Custom
Re: 383

Quote:
Originally Posted by strc09
Thanks for the info fellas.

The reason they still need a little work is because the bottom side of the heads around a couple of the cylinders have some gouges so they probably won't seat correctly. Nothing really deep so that's a good thing. Like Cliff mentioned previously just flattened.

I'll go back to that store and see if I can find a set of self aligning in that style. When you say didn't run right, why wouldn't the car run right? As for the rocker coming off...yeah, I had that happen to me before while I was cruising about 85 down I95 in my 66 LeMans. I thought my freakin' motor blew up on me. Lucky that's all it was because I was a ways from home and thet would have been an expensive tow bill. LOL!
the car did run right, the rockers didn't work right. they didn't ride right on the valve stem, and one actually came off. others were trying to do it when the problem happened. the car did run right up until the very minute that it happened. i would definitely look for self-aligning rockers.
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87 GTA: Forged 408 LSX short block, TEA stage 2 cnc ported 243 heads, BTR Stage 3 stroker cam, Fast 102 intake, NW 102 TB, Longtube headers, custom 411 ECM, custom harness, custom tuned, Performabuilt stage 2 4l60E with PTC 2800 stall, 9 bolt rear with 3.70 gears and TAP girdle.

11.16 at 123 mph.
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Old 07-24-2007   #90
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Would this cam work?

http://www.cnc-motorsports.com/produ...D=12909&CtgID=
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-24-2007   #91
FearThisGTA
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

It will but I would go with a roller instead.
__________________


Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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Old 07-24-2007   #92
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

What's the difference between the two styles?
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-24-2007   #93
MunsonGTA
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GTA Year: 1987
GTA Engine: Custom
Re: 383

Quote:
Originally Posted by strc09
What's the difference between the two styles?
you have a roller motor, you need a roller cam. roller cams are much better anyways. that cam you posted is way too weak for a 383. i run bigger then that in my 350 and my cam is too weak in my opinion.
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87 GTA: Forged 408 LSX short block, TEA stage 2 cnc ported 243 heads, BTR Stage 3 stroker cam, Fast 102 intake, NW 102 TB, Longtube headers, custom 411 ECM, custom harness, custom tuned, Performabuilt stage 2 4l60E with PTC 2800 stall, 9 bolt rear with 3.70 gears and TAP girdle.

11.16 at 123 mph.
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Old 07-24-2007   #94
FearThisGTA
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

Thats why I say call Comp Cams tech line and ask them. Tell them what you have and they can fix you up OR you can go on their website and send them an email if you like. They usually will email you back with in a day.
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Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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Old 07-24-2007   #95
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Okay...I'll try that instead. Thanks fellas.
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-31-2007   #96
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Still waiting to hear back from Comp Cams...
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-31-2007   #97
strc09
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Finally had to call Comp Cams to get some help since I couldn't get an e-mail back from them after a week of waiting. I really think the guy gave me a custom grind instead of helping me select once that is already done. Not that it's a bad thing, but there's no price. It's probably going to be more expensive than selecting one that's already done which will keep my GTA in the driveway longer. Grrr...
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-31-2007   #98
FearThisGTA
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

Custom grinds are usually a little more but not much.
__________________


Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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Old 07-31-2007   #99
strc09
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Location: Linden, NC
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GTA Year: 1988
GTA Engine: Custom
Re: 383

Yeah...I wish he would have given me a price. Now I have to call them back and sit on hold forever to get a price. Grrr...
__________________
-Patrick

GTA: Grand Turismo Americano (Grand Touring America)
1 of 930 1988 Gunmetal Metallic GTAs produced (RPO 87U)
Built by Zeus Performance and tuned by Alvin from PCM4Less
Check out my website: Night Vision GraFX
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Old 07-31-2007   #100
FearThisGTA
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GTA Year: 1991
GTA Engine: 350 TPI Automatic
Re: 383

He cant give you a price and if he did it would be high, jsut get the part# and grind and give the part # to whoever you buy your parts from and they can give you a price. hth
__________________


Cliff Jones
1991 GTA Trans Am
w/305,231 miles
on the original motor!!!!
Time of Death on motor, 4:07pm on 05/29/2010.
Hp:211.2@4200rpms/Tq.328.5@2700rpms
Best et: 13.959@97.05mph
Best mph: 98.3
Best 60' : 1.875 on BFG Comp TA's w/ 32 lbs of air in them
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