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330rwhp/330 rwtq. Not enuf. Here is my stuff: 383, Edelbrock Vic. Jr. heads (215 cc, 2.08/1.60), C.R. 10.25, Vic. Jr. intake w/1 in. spacer, 6 in rods, Crower 00426S cam, soild roller (250/252@.050, .570,.584,lsa=112, 108 centerline), Holley 750dp., 1-3/4 in. headers, 2.5 in. w/ 40 series Flow's. I'm thinking cam is too big (dyno shows still climbing at 6,500.) Any suggestions? TIA
YOUR COMBO. DOES NOT SEEM THAT FAR OFF TO ME OTHER THAN THE PORT VOLUME OF THE HEADS IS A LITTLE LARGE.I WOULD THINK IT WOULD WORK BETTER WITH SAY 190 CC HEAD OR A WELL PORTED 180 CC HEAD.WHAT COULD BE HAPPENING IS YOUR CAM IS OUT OF IT'S POWER BAND BEFORE THE HEADS ARE.Quote:
Originally posted by big_G1
330rwhp/330 rwtq. Not enuf. Here is my stuff: 383, Edelbrock Vic. Jr. heads (215 cc, 2.08/1.60), C.R. 10.25, Vic. Jr. intake w/1 in. spacer, 6 in rods, Crower 00426S cam, soild roller (250/252@.050, .570,.584,lsa=112, 108 centerline), Holley 750dp., 1-3/4 in. headers, 2.5 in. w/ 40 series Flow's. I'm thinking cam is too big (dyno shows still climbing at 6,500.) Any suggestions? TIA
put it on the bottle.............
Is the hp still climbing or the torque?
LOBE SEPERATION IS GOOD FOR N20 BUT IT WOULD WORK A LOT BETTER IF HE HAD MORE EXHAUST DURATION.Quote:
Originally posted by 86Diablo
put it on the bottle.............
The hp is still climbing. The cam is spec'ed for 7000 max hp, 7500 redline.Quote:
Originally posted by 76GMC1500
Is the hp still climbing or the torque?
THIS COMBO. SHOULD DO ANY EASY 500 OR A LITTLE MORE AT THE FLEXPLATE.WHAT ARE WE MISSING?Quote:
Originally posted by big_G1
330rwhp/330 rwtq. Not enuf. Here is my stuff: 383, Edelbrock Vic. Jr. heads (215 cc, 2.08/1.60), C.R. 10.25, Vic. Jr. intake w/1 in. spacer, 6 in rods, Crower 00426S cam, soild roller (250/252@.050, .570,.584,lsa=112, 108 centerline), Holley 750dp., 1-3/4 in. headers, 2.5 in. w/ 40 series Flow's. I'm thinking cam is too big (dyno shows still climbing at 6,500.) Any suggestions? TIA
Well, if you allow 30% loss in the drivetrain, it's makin' 470 at the flexplate. Pull the plugs, wire the throttle blades open and check cylinder pressure. I think I'd have backed off on the intake volume in the heads if I used a cam that made power to 7,500. In my opinion, you've got more heads than cam.
When I was looking at head flow numbers, the Vic.'s did not flow as well as AFR 190's or 195's. Now I have to decide how to pick up the torque. Smaller runners? Or will a cam with less duration and overlap raise the torque enough to bring the hp. up enough at 6500 rpm? (I don't have to rev. to 7000 rpm). My cranking compression is 150 psi.Quote:
Originally posted by techinspector1
Well, if you allow 30% loss in the drivetrain, it's makin' 470 at the flexplate. Pull the plugs, wire the throttle blades open and check cylinder pressure. I think I'd have backed off on the intake volume in the heads if I used a cam that made power to 7,500. In my opinion, you've got more heads than cam.
I agree, the heads are too big,......sucks though, they are'nt cheap.......but you definately have a problem, those numbers are far from what is expected from your combo.....some times when building a motor camshaft selection and port volume are missed. I would suggest a smaller port volume as stated in an earlier post......
YES,THE SMALLER PORT VOLUME WILL HELP.THE WHOLE IDEA IS TO HAVE A SMALLER PORT VOLUME AND GREAT FLOW NUMBERS.THERE IS STILL SOMETHING WAY OFF.330 RWHP IS WAY TO LOW.GO BACK AND CHECK EVERYTHING YOU CAN THINK OF TIMING,JETTING ETC.Quote:
Originally posted by big_G1
When I was looking at head flow numbers, the Vic.'s did not flow as well as AFR 190's or 195's. Now I have to decide how to pick up the torque. Smaller runners? Or will a cam with less duration and overlap raise the torque enough to bring the hp. up enough at 6500 rpm? (I don't have to rev. to 7000 rpm). My cranking compression is 150 psi.
I'd be changin' the cam to one with an earlier intake closing point to raise the cylinder pressure to around 170-180 if I had a good tight squish in the motor.
Yea, I think that would be the less costly route, maybe a 230/236. That and I'll keep my ears open for some AFR190's...lol..Thanks for the good advice.Quote:
Originally posted by techinspector1
I'd be changin' the cam to one with an earlier intake closing point to raise the cylinder pressure to around 170-180 if I had a good tight squish in the motor.
I think Erik is right. Something aint right. Check the balancer, to see if the deg. marks are correct. You may have a small vacuum leak or running a little lean. Just check everything and check it again.
Sometimes you over look some of the dumbest things and kick yourself after. LOL
Yea, been all around this problem for a while. Good SFI balancer, tried 30 to 40 deg total advance,(not any power above 34 deg.) all in by 2300. O2 sensor on dyno shows 12.5 a/f ratio, tried BG850 Mighty Demon as well as the Holley 750 dp. I'm gonna degree the cam this weekend just to see how it was installed, then pull it to check the part no. and lobes. BTW, it runs 12.40's, but I know I'm down a bunch...Quote:
Originally posted by Joe Scalley
I think Erik is right. Something aint right. Check the balancer, to see if the deg. marks are correct. You may have a small vacuum leak or running a little lean. Just check everything and check it again.
Sometimes you over look some of the dumbest things and kick yourself after. LOL
THIS,WASNT,WHAT,I,WANTED,QUOTED,OOPS!!Quote:
Originally posted by erik erikson
YOUR COMBO. DOES NOT SEEM THAT FAR OFF TO ME OTHER THAN THE PORT VOLUME OF THE HEADS IS A LITTLE LARGE.I WOULD THINK IT WOULD WORK BETTER WITH SAY 190 CC HEAD OR A WELL PORTED 180 CC HEAD.WHAT COULD BE HAPPENING IS YOUR CAM IS OUT OF IT'S POWER BAND BEFORE THE HEADS ARE.
Cam is completely wrong for any given application. Not enough exhaust duration for N2O or forced induction. Too wide lobe separation angle for naturally aspirated. Same cam on a 106 lsa and istalled 4 degrees advanced would yield about anywhere from 40-60 more horses. Also you wouldn't have to spin it to 7g's to make HP.
One of my combos'
--383cid
--victor jr. intake
--dart 215cc heads
--holley 750hp
--comp solid roller 252/258@.050 .630/.630 1.6in/1.5ex rockers
--10:1 cr
Dyno'd lil over 500hp and 485 ft lbs all below 6200
your cam may be bleeding cylinder pressure on the exhaust side because I have 200lbs cranking pressure. I run pump gas with a 0 deck and .039 head gasket. I run 36 degrees timing and 76/84 jets in the carb. 3" exhaust, 40-series flowmasters.
Thanks, Ray...BTW what is the part number on your Comp cam?
yea make sure ur carb is tuned right , that can make a big difference
THE WIDE LOBE SEPERATION GIVES YOU A LITTLE WIDER POWER BAND.YOU ALSO STATE BY HAVING THE CAM GROUND ON 106 L/S AND IN STALLING IT AT 4 DEGREES IT WILL GIVE IT 40-60 MORE H.P.I REALLY WISH IT WHERE THAT SIMPLE.Quote:
Originally posted by camaro_fever68
THIS,WASNT,WHAT,I,WANTED,QUOTED,OOPS!!
Cam is completely wrong for any given application. Not enough exhaust duration for N2O or forced induction. Too wide lobe separation angle for naturally aspirated. Same cam on a 106 lsa and istalled 4 degrees advanced would yield about anywhere from 40-60 more horses. Also you wouldn't have to spin it to 7g's to make HP.
One of my combos'
--383cid
--victor jr. intake
--dart 215cc heads
--holley 750hp
--comp solid roller 252/258@.050 .630/.630 1.6in/1.5ex rockers
--10:1 cr
Dyno'd lil over 500hp and 485 ft lbs all below 6200
your cam may be bleeding cylinder pressure on the exhaust side because I have 200lbs cranking pressure. I run pump gas with a 0 deck and .039 head gasket. I run 36 degrees timing and 76/84 jets in the carb. 3" exhaust, 40-series flowmasters.
Man, that camshaft is way too big for a 10.5:1 compression motor, with the 215cc runners it is having a hard time breathing in that much volume. With your relatively low compression you should be runing a camshaft with around 236@.050"....also a runner volume of around 180-190.....this is why you have low numbers, your compression can't support that camshaft. This is obviously a race motor, so you are eother going to have to run a way higher compression or stab in a smaller cam and head package. You can't mismatch the head and camshaft.....this is what will happen.....Jmo
Erik, you are right hands down on that the power band is wider on a wide LSA. The problem is that comes at the expense of torque and horse power throughout the wider rpm range. IN short the engine needs the 106 LSA for better scavenging intake vacuum during overlap. Proper cam design is as important as proper head design and those 215 runners are not to big for a 383. The cam is the place to start, and it is that simple. Advancing the cam 4 degrees is going to trap more cylinder pressure for one and make more bottom end power to keep the engine from having to spin to 7g's to make it's power,,,for,two.Quote:
Originally posted by erik erikson
THE WIDE LOBE SEPERATION GIVES YOU A LITTLE WIDER POWER BAND.YOU ALSO STATE BY HAVING THE CAM GROUND ON 106 L/S AND IN STALLING IT AT 4 DEGREES IT WILL GIVE IT 40-60 MORE H.P.I REALLY WISH IT WHERE THAT SIMPLE.
My Comp part no. is 12-900-9, I run a 850 Proform DP, my cam is installed on a 102 intake centerline, I have 200psi cranking pressure. I run 32x18.5 Mickey Sportman PRO's 4.11 gear TH-350, 2500 stall. It equals out to a 1.55 60ft. 11.20's ET@122mph crossing the line @61-6200RPM all on motor and pump gas. The only thing wrong with this combo is stall but if I went up on it I wouldn't hook on the street.
The RPM range listed on my cam is 3200-6200.
P.S. I know engine vacuum is dead low during overlap. When I refer to intake vacuum I am refering to the rushing exhaust gasses drawing intake charge into the cylinder. That is why tuning collector length can play a big part in engine tuning. Had to say that so my buddy wouldn't get :confused:
Erik, You must've missed this one. I don't think he's saying he wants more RPM range here. I think he wants more usable power under 6500. Can't wait to see how your arrogance picks this one apart. In SIMPLE terms I'd appreciate you don't quote me no more. ThanksQuote:
Originally posted by big_G1
When I was looking at head flow numbers, the Vic.'s did not flow as well as AFR 190's or 195's. Now I have to decide how to pick up the torque. Smaller runners? Or will a cam with less duration and overlap raise the torque enough to bring the hp. up enough at 6500 rpm? (I don't have to rev. to 7000 rpm). My cranking compression is 150 psi.
Also I would like to point out what is your lobe seperation ? most SBC 383 naturally aspirated cams like a lobe seperation of 104 to 106 degrees. Remember that the 383 is a large displacement motor that can rev, specially if it is internally balanced, so most stock SBC heads only barely get the job done. First off I would get hold of a dynamic compression ratio calculator. Because remember the most important engine power making event is when the intake valve closes. Cam design and static compression ratio work together to give an actual running compression ratio, which is called dynamic compression ratio and is a much more accurate engine building and design tool.:)
YOU ARE OBVIOUSLY MISTAKEN.I WANT TO TRY AND HELP PEOPLE.CAMARO FEVER68 I WILL STOP QUOTING YOU WHEN YOU STOP MAKING FALSE CLAIMS AND STATMENTS.THERE ARE A LOT OF YOUNG PEOPLE ON THIS FORUM AND WHEN YOU POST B.S. THEY MIGHT THINK IT IS TRUE.REALLY 40-60 H.P. BY HAVING THE CAM GROUND ON 106 L/S AND INSTALLLING IT 4 DEGREE'S ADVANCED.STOP IT YOUR KILLING ME.I WAS BORN AT NIGHT BUT NOT LAST NIGHT.YOU CAN QUOTE THAT IF YOU WANT L.O.L. :whacked:Quote:
Originally posted by camaro_fever68
Erik, You must've missed this one. I don't think he's saying he wants more RPM range here. I think he wants more usable power under 6500. Can't wait to see how your arrogance picks this one apart. In SIMPLE terms I'd appreciate you don't quote me no more. Thanks
The only B.S. on this site is you thinking you know it all. If you can't understand simple scavenging you don't know engines. If his lsa would've been about 110 he would gain less hp going to 106 as if it was 108 he would gain even less. 112 is way off and installing it 4 degrees advance would help build more cylinder pressure. Do your homework and post to the sites, don't try to be a know it all when you are nothing but full of B.S. I'm not giving opinions, I'm stating what worked for me in experience, not theory. The problem with people like you is YOU KNOW IT ALL. I haven't seen you actually give helpful advise to anybody. Instead you like to contradict others like Denny and so forth that I know and have seen there advise and have no question that They know what they're doing. If I answer a post on here, it's going to be straight forward what I know will work...Nuff Said, I'm out the pissing contest with you..keep your B.S. and your arrogance to yourself.....Quote:
Originally posted by erik erikson
YOU ARE OBVIOUSLY MISTAKEN.I WANT TO TRY AND HELP PEOPLE.CAMARO FEVER68 I WILL STOP QUOTING YOU WHEN YOU STOP MAKING FALSE CLAIMS AND STATMENTS.THERE ARE A LOT OF YOUNG PEOPLE ON THIS FORUM AND WHEN YOU POST B.S. THEY MIGHT THINK IT IS TRUE.REALLY 40-60 H.P. BY HAVING THE CAM GROUND ON 106 L/S AND INSTALLLING IT 4 DEGREE'S ADVANCED.STOP IT YOUR KILLING ME.I WAS BORN AT NIGHT BUT NOT LAST NIGHT.YOU CAN QUOTE THAT IF YOU WANT L.O.L. :whacked:
I APOLOGIZE TOO ANYONE AND EVERYONE READING THESE LAST FEW POST. EVERYONE IS ENTITLED TO HIS/HER OWN WITHOUT SOMEONE ELSE BELITTLING THEM. ANYTHING I LIST IN THESE FORUMS WILL BE JUST LIKE MY SIGNATURE HAS SAID FROM THE START. IF I HAVEN'T EXPERIENCED IT OR DONE IT, I WON'T ANSWER IT. I'M STILL LEARNING EVERYDAY AND SOME THINGS I HAVE TO ASK IN THE FORUM ALSO. I'M STILL EXPERIMENTING WITH WATER/ALCOHOL INJECTION AND MY FIRST BLOWER MOTOR.
Thanks for the replies guys...Using Wallace Racing's D.C.R. program, it comes up with 8.87:1, with a cranking compression of 181 psi. (My tests show 150 psi dry.) Intake valve closes at 53.0 ABDC, btw. I am considering the Comp cams 280AR or XR274R...any thoughts?Quote:
Originally posted by southerner
Also I would like to point out what is your lobe seperation ? most SBC 383 naturally aspirated cams like a lobe seperation of 104 to 106 degrees. Remember that the 383 is a large displacement motor that can rev, specially if it is internally balanced, so most stock SBC heads only barely get the job done. First off I would get hold of a dynamic compression ratio calculator. Because remember the most important engine power making event is when the intake valve closes. Cam design and static compression ratio work together to give an actual running compression ratio, which is called dynamic compression ratio and is a much more accurate engine building and design tool.:)
Quote:
Originally posted by big_G1
Thanks for the replies guys...Using Wallace Racing's D.C.R. program, it comes up with 8.87:1, with a cranking compression of 181 psi. (My tests show 150 psi dry.) Intake valve closes at 53.0 ABDC, btw. I am considering the Comp cams 280AR or XR274R...any thoughts?
:cool: Glad to help :3dSMILE:
It all depends on what you want to do with the motor. If you want pro street, which is what you just about have to do with the rest of the combo, you should consider the comp 288AR-6. It requires a 10:1 CR and a 3500 stall. It is a .420 Hi-Tech roller that is designed to be easy on parts. I have been running it for a year in my 383 with no problems. I drive it around town but not on the highway or anything. I think if you go too low on the cam with those heads you will kill power because you will not have enough velocity in those big intake runners. You have to decide what to do in this case. The problem is that if you want a tamer, more streetable engine, you are going to have to start over at the short-block. The heads and intake are performance oriented. I'm running close to the same combo, but with a small converter for the street. I think a 3500 stall would put me in the 10's. I went to a proform 850dp and it didn't help or hurt, so now I got it on a 420sbc.:3dSMILE:Quote:
Originally posted by big_G1
Thanks for the replies guys...Using Wallace Racing's D.C.R. program, it comes up with 8.87:1, with a cranking compression of 181 psi. (My tests show 150 psi dry.) Intake valve closes at 53.0 ABDC, btw. I am considering the Comp cams 280AR or XR274R...any thoughts?
Thanks for the advice. I called Comp Cams earlier today, they recommended a very similar cam, XR280R. I ordered it today. Thanks for all your help, I'll let you know how it worked out.Quote:
Originally posted by camaro_fever68
It all depends on what you want to do with the motor. If you want pro street, which is what you just about have to do with the rest of the combo, you should consider the comp 288AR-6. It requires a 10:1 CR and a 3500 stall. It is a .420 Hi-Tech roller that is designed to be easy on parts. I have been running it for a year in my 383 with no problems. I drive it around town but not on the highway or anything. I think if you go too low on the cam with those heads you will kill power because you will not have enough velocity in those big intake runners. You have to decide what to do in this case. The problem is that if you want a tamer, more streetable engine, you are going to have to start over at the short-block. The heads and intake are performance oriented. I'm running close to the same combo, but with a small converter for the street. I think a 3500 stall would put me in the 10's. I went to a proform 850dp and it didn't help or hurt, so now I got it on a 420sbc.:3dSMILE:
big_G1, what stall are you running. Stall converters will give you some lower numbers on the dyno torque and HP. The bigger the stall the worse it gets.
I'm still a 3 pedal guy, but I don't understand how a hi stall converter would lower torque and horsepower on a chassis dyno. Is the slippage that bad, or what????
5 Speed Richmond, 3.08 rear axle, dyno pulls in 4th gear....Quote:
Originally posted by 73RS
big_G1, what stall are you running. Stall converters will give you some lower numbers on the dyno torque and HP. The bigger the stall the worse it gets.
What are the plans with this engine? Prostreet, mostly strip, Hot street, daily driver(hope not) That 280 is a decent cam and might make some more horses. It on a 110 lsa, calls for 10:1 CR and wants a 2800 stall with 3.73-3.90 rear gear. You might wanna go to www.racingjunk.com and list those heads for trade or something. They are a little to much to try to tame down and produce decent torque levels. Horsepower will come but higher in the RPM range.Quote:
Originally posted by big_G1
Thanks for the advice. I called Comp Cams earlier today, they recommended a very similar cam, XR280R. I ordered it today. Thanks for all your help, I'll let you know how it worked out.
This is in a 3100 lb. 68 Vette, Richmond 5 speed. Pro-Street/strip use. Not a daily driver. I have a buddy with same heads/cam, only a 406 and he is making 400/400 at the wheels. He is using 1.6 rockers, tho. I figure with my 1.5 rockers, my numbers will be close to his.Quote:
Originally posted by camaro_fever68
What are the plans with this engine? Prostreet, mostly strip, Hot street, daily driver(hope not) That 280 is a decent cam and might make some more horses. It on a 110 lsa, calls for 10:1 CR and wants a 2800 stall with 3.73-3.90 rear gear. You might wanna go to www.racingjunk.com and list those heads for trade or something. They are a little to much to try to tame down and produce decent torque levels. Horsepower will come but higher in the RPM range.