Got Cam Recommendation, does it look right?
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,672
Likes: 8
From: Sumter South Carolina
Got Cam Recommendation, does it look right?
I called comp cams and got their recommendation of cam for my engine. Wanted to make sure it all looks right. Also talking with a dealer for AFR heads and about to finalize purchase but still on edge about the head size.
383 Stroker in my 1989 manual vette
Need a lot of high end rpm because used for almost entirely Road Racing NASA/SCCA. Want to be able to hold a gear close or to 7000 RPM. Also in Autocross I always need more 2nd gear (3rd hardly ever worth shifting for).
Intake will be a USM ported Holley Stealth Ram
AFR Head either 210cc or 220 (would like to hear recommendations. my thoughts are go bigger in case of future modification)
Will be using a 5.7 Rod (thinking of a 6. I want reliability over power)
The Cam Recommended is: http://www.compcams.com/Company/CC/c...?csid=161&sb=2
Thing that makes me a bit weary is it looks too small. I am going to use a 1.6 Roller rocker so the specs change to 251/258 550intake 568 exhaust, but still seems a bit small... He said it makes power from 2000 to 6300. Could I hold a gear up to 7000? That seems a long way a way from 6300.
383 Stroker in my 1989 manual vette
Need a lot of high end rpm because used for almost entirely Road Racing NASA/SCCA. Want to be able to hold a gear close or to 7000 RPM. Also in Autocross I always need more 2nd gear (3rd hardly ever worth shifting for).
Intake will be a USM ported Holley Stealth Ram
AFR Head either 210cc or 220 (would like to hear recommendations. my thoughts are go bigger in case of future modification)
Will be using a 5.7 Rod (thinking of a 6. I want reliability over power)
The Cam Recommended is: http://www.compcams.com/Company/CC/c...?csid=161&sb=2
Thing that makes me a bit weary is it looks too small. I am going to use a 1.6 Roller rocker so the specs change to 251/258 550intake 568 exhaust, but still seems a bit small... He said it makes power from 2000 to 6300. Could I hold a gear up to 7000? That seems a long way a way from 6300.
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,672
Likes: 8
From: Sumter South Carolina
I told him it has been ported to flow 290cc per runner. It just seemed like when I was asking him specific questions all he was doing was plugging it into their program and seeing what happened...
What other company can I call for a second opinion?
What other company can I call for a second opinion?
Melting Slicks
Joined: Nov 2000
Posts: 2,469
Likes: 6
From: Winchester Ontario
Have you looked at Lunati Voodoo 60123? More lift and some more duration.
http://www.summitracing.com/int/part...0123/overview/
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
210 comp port should do the job ifits 7k max get the best head for the build now and it will run right
If I were running a motor up to 7 and holding it there or close I wouldnt even bother with a hydraulic put a solid in there and really make some power. no risk of lifters pumping up and hurting things. with a qualtiy rocker setup youll only have to ck lash 1 or 2 x a yr if that. where do you want your power to start and stop, gear ratio?
If I were running a motor up to 7 and holding it there or close I wouldnt even bother with a hydraulic put a solid in there and really make some power. no risk of lifters pumping up and hurting things. with a qualtiy rocker setup youll only have to ck lash 1 or 2 x a yr if that. where do you want your power to start and stop, gear ratio?
Last edited by cv67; Jul 1, 2014 at 10:42 AM.
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
what computer setup are you going to run it ? dont forget that if you go crazy with the cam its going to be difficult to tune an efi,
I would find the people on here who have stealth ram setups or have built them and ask them what sort of cam to use, you will probably get better info on CF.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Cuisinart also knows his stuff. For 7k rpm, solid roller sounds the way to go. Shaft rockers I'm guessing too.
6" rods make more top-end power so that's what you want. They aren't any less reliable.
Consider oiling and windage tray with your build.
Bullet cams will work with you to determine a custom cam.
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
210 comp port should do the job ifits 7k max get the best head for the build now and it will run right
If I were running a motor up to 7 and holding it there or close I wouldnt even bother with a hydraulic put a solid in there and really make some power. no risk of lifters pumping up and hurting things. with a qualtiy rocker setup youll only have to ck lash 1 or 2 x a yr if that. where do you want your power to start and stop, gear ratio?
If I were running a motor up to 7 and holding it there or close I wouldnt even bother with a hydraulic put a solid in there and really make some power. no risk of lifters pumping up and hurting things. with a qualtiy rocker setup youll only have to ck lash 1 or 2 x a yr if that. where do you want your power to start and stop, gear ratio?
For 7000rpm, you are talking about a race motor and you don't need the extra weight of hydraulic rollers. One thing that hasn't been asked is what your compression ratio is. That has a lot to do with cam selection. A 383 is inherently a torquer motor based on it's bore/stroke ratio. If you are looking for high rpm horsepower, a 377 would fit your needs better.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,672
Likes: 8
From: Sumter South Carolina
All things I told to the guy when he made the recommendation... hmm.
Problem is I already have a set of 1.6 roller rockers crane golds. I need to use them to be able to spend all I can on the bottom end. The competition afr 210 or 220 will be good flow and feed it. Only thing I was thinking is upgrading the springs to handle over .600 lift.
Compression: shooting for 10.5:1 still run 93 octane
ecu: holley commander
bosch III injectors 40lb
Ill go with 6" rods (just always heard its tough on cylinder walls)
Rear gear is 3.73 6-speed zf6 black tag, spec flywheel/clutch 2+
usm holley stealth ram ported and cut to fit under hood
Already have remote oil cooler and canton rr pan.
cam is what is in the air
I already have a summit block 1 piece rms fit for hydraulic cam. Everyone ive talked to so far says I dont need flat tappet and should be fine for hydraulic. I need to hold up to 7k but just get there. Not pull. If I make peak power at 6500 I think with a good cam and stable valve train and balanced block shouldnt be a problem. I dont need it all the time, just in certain instances.
Problem is I already have a set of 1.6 roller rockers crane golds. I need to use them to be able to spend all I can on the bottom end. The competition afr 210 or 220 will be good flow and feed it. Only thing I was thinking is upgrading the springs to handle over .600 lift.
Compression: shooting for 10.5:1 still run 93 octane
ecu: holley commander
bosch III injectors 40lb
Ill go with 6" rods (just always heard its tough on cylinder walls)
Rear gear is 3.73 6-speed zf6 black tag, spec flywheel/clutch 2+
usm holley stealth ram ported and cut to fit under hood
Already have remote oil cooler and canton rr pan.
cam is what is in the air
I already have a summit block 1 piece rms fit for hydraulic cam. Everyone ive talked to so far says I dont need flat tappet and should be fine for hydraulic. I need to hold up to 7k but just get there. Not pull. If I make peak power at 6500 I think with a good cam and stable valve train and balanced block shouldnt be a problem. I dont need it all the time, just in certain instances.
Burning Brakes
Joined: Jun 2005
Posts: 1,188
Likes: 13
From: Wallingford Vermont
Ill go with 6" rods (just always heard its tough on cylinder walls)
I think you got it backwards, short rods should induce more side loading - scuffing of cylinder walls. That's why the 400 cu in small blocks wore out so fast (relatively) was the 5.565" rod with a 3.75 stroke.
Does anyone find it curious (besides me) that AFR recommends a dual pattern cam? I mean: AFR has some of the best I/E flow rates in the industry (upper 70% - 80% I/E ratio), his exhaust will be full competition (so no restriction there), why go big on exhaust duration? (and give up that mid-range pull)
Last edited by DanZ51; Jul 1, 2014 at 02:28 PM.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
I'm no expert but,
Does anyone find it curious (besides me) that AFR recommends a dual pattern cam? I mean: AFR has some of the best I/E flow rates in the industry (upper 70% - 80% I/E ratio), his exhaust will be full competition (so no restriction there), why go big on exhaust duration? (and give up that mid-range pull)
Does anyone find it curious (besides me) that AFR recommends a dual pattern cam? I mean: AFR has some of the best I/E flow rates in the industry (upper 70% - 80% I/E ratio), his exhaust will be full competition (so no restriction there), why go big on exhaust duration? (and give up that mid-range pull)
Melting Slicks
Joined: Oct 2000
Posts: 2,158
Likes: 9
From: N.E. WA
Good point here. Most dual pattern cams favor the intake with increased duration. Exhaust gasses pretty much explode out the port and don't need as much time to exhaust as the intake needs to suck in the charge. Also, that cam is recommended for a 9.0 compression ratio. 10.5 is quite a difference.
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
Try this; exhaust valves are smaller so the duration needs to be longer to get the gasses out.
Last edited by 383vett; Jul 1, 2014 at 05:15 PM.
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,672
Likes: 8
From: Sumter South Carolina
I pmed bjankuski but no response yet. What should be my next move? Should I call comp cams again and try to get someone else? Or try a different company? Or make a new post called "need cam recommendation"? Last thing I want to do is leave power and rpms on the table.
Usually people end up regretting an aggressive cam because they loose drivability and low end torque. Both of which I have no use for. I need this thing to pull hard to 6500 and then not be under 250hp by 7000.
Ive seen some third gen guys slap stealth rams on and get some very unimpressive numbers with inadequate cam and 190cc heads. Making me worried. I would be satisfied with 400 to the wheels but nothing less.
Usually people end up regretting an aggressive cam because they loose drivability and low end torque. Both of which I have no use for. I need this thing to pull hard to 6500 and then not be under 250hp by 7000.
Ive seen some third gen guys slap stealth rams on and get some very unimpressive numbers with inadequate cam and 190cc heads. Making me worried. I would be satisfied with 400 to the wheels but nothing less.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Does anyone find it curious (besides me) that AFR recommends a dual pattern cam? I mean: AFR has some of the best I/E flow rates in the industry (upper 70% - 80% I/E ratio), his exhaust will be full competition (so no restriction there), why go big on exhaust duration? (and give up that mid-range pull)
One reason I suggested talking to Brian about the USR HSR is power limitations. I think he had some frustrations and had to rework it quite a bit. I also wonder if he thinks a MR would be better for your power range? I was thinking the HSR was better for a 6200-6500 RPM setup.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
some good points here. You can run a single pattern cam with the afrs but running a split pattern can carry the power a little farther up. At that point its all about valve opening and closing events. You can have your cake and eat it too without blowing all your torque out the exhaust.
Try getting ahold of someone like Mamo, Chris Straub or the likes for the the "right" cam. Comp tech guys can only spend so much time
Im thinking there are some good off the shelf cams that will work fine just geting the right one. only about a bazillion cams have been ground for the sbc.
Sounds lke youre stuck on a HR...if you did go solid know most co's are making bushed rollersnow so no needle bearings to go bad couple that with a ramp that isnt too "extreme" you should have long life with either type of cam
Try getting ahold of someone like Mamo, Chris Straub or the likes for the the "right" cam. Comp tech guys can only spend so much time
Im thinking there are some good off the shelf cams that will work fine just geting the right one. only about a bazillion cams have been ground for the sbc.
Sounds lke youre stuck on a HR...if you did go solid know most co's are making bushed rollersnow so no needle bearings to go bad couple that with a ramp that isnt too "extreme" you should have long life with either type of cam
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,672
Likes: 8
From: Sumter South Carolina
Its not that im stuck on the hsr, its more that is what I have. It would tack another $1000 on the price tag for a miniram. Im already over budget because I sprang for the afr heads. I know I could sell the hsr for some but thats not cash in hand. I would rather spec a cam with some growing room in it and swap later than sacrifice my rpm.
I hope I can speak to brian soon. Im about to have to order parts and get this thing started or it wont be done by aug when I have to go back to work.
I hope I can speak to brian soon. Im about to have to order parts and get this thing started or it wont be done by aug when I have to go back to work.
Melting Slicks
Joined: Oct 2000
Posts: 2,158
Likes: 9
From: N.E. WA
Just keepin ya honest. No worries, we've all been there.