crazypete said:
No offense meant here Pete, but you need to go back in and degree the cam in - it bolts to the crank by the way. This and valve train setup could be where your HP is hiding. How did you determine pushrod length?
Disappointment at the dyno: 227 rwhp with afr165's and custom cam
- Thread starter crazypete
- Start date
No offense meant here Pete, but you need to go back in and degree the cam in - it bolts to the crank by the way. This and valve train setup could be where your HP is hiding. How did you determine pushrod length?
The way you described fixing the pushrod problem, leads me to believe that you have not checked you pushrods correctly. If your push rods are too short, you will not be opening the valves to there full distance the cam dictates. If they are too long, you will bend a pushrod or your valves will not close/seat all the way either. Check out this link about measuring pushrod length ..
http://www.mustangcentral.net/tech/geometry.html
*note* also make sure to look at the link about making your own "checking" lifter out of a old hyd lifter..very useful
Also, the term "degreeing a cam" is sometimes a little confusing..You are actually making sure the 'valvetrain events" (ie valves opening closing) are timed correctly in relation to the crank/piston postion or event. So the degree wheel bolts to the fly wheel and the dial indicator is resting on you rocker are or push rod, you can (very accuratly) make sure that at xdeg after BTDC your valve is opening when the spec sheet says its supposed to..If you buy a real degree kit, it should come with a deg wheel, dial indicator w/ mag base and a howto video...go to comp cams or summit.
http://www.mustangcentral.net/tech/geometry.html
*note* also make sure to look at the link about making your own "checking" lifter out of a old hyd lifter..very useful
Also, the term "degreeing a cam" is sometimes a little confusing..You are actually making sure the 'valvetrain events" (ie valves opening closing) are timed correctly in relation to the crank/piston postion or event. So the degree wheel bolts to the fly wheel and the dial indicator is resting on you rocker are or push rod, you can (very accuratly) make sure that at xdeg after BTDC your valve is opening when the spec sheet says its supposed to..If you buy a real degree kit, it should come with a deg wheel, dial indicator w/ mag base and a howto video...go to comp cams or summit.
tmoss said:
I didnt. I asked Ed and he said the factory pushrods were what I should be using. So I shimmed the rockers properly and took his advice of reusing the pushrods since they were in good shape. If they were too short, they would eat some of the 580/570 lift up and eat a few hp but I somehow think...just sitting here that it would still be enough lift to get some nice numbers regarless. If they were too long, with the lift on the cam and the 1.7 roller rockers, they would bind up the springs since it is so close to coil bind anyway.
I'm not trying to be difficult, just trying to armchair philosophize about the valvetrain setup from work before I dive in and start tearing my daily driver apart.
I need to do a compression test tonight cause my gut is telling me that maybe the rockers are NOT properly shimmed and I have a valve or two hanging open. Something is eating my mpg and it's not all the extra power, thats for sure. I dont know, I did get a new clutchfan....
Furthermore, it seems from last night's test that this torque converter is acting as a 2000-2200 maybe 2500 stall. So he ground the cam for a different converter.
Woodrow
Founding Member
Have you called Ed and to see what he had to say?
If I had to guess you either installed the cam wrong or the timing is severely retarded. Just look at how wavy the graph is something is not jiving with the a/f, timing imo...
I'll also say that if you didnt have the a/f check at the dyno you need to, XP8 is right those gauges are only good for looks. FYI I had a problem witht eh a/f (lean) when it was fixed I gained 30 hp 36tq at the wheels.
If I had to guess you either installed the cam wrong or the timing is severely retarded. Just look at how wavy the graph is something is not jiving with the a/f, timing imo...
I'll also say that if you didnt have the a/f check at the dyno you need to, XP8 is right those gauges are only good for looks. FYI I had a problem witht eh a/f (lean) when it was fixed I gained 30 hp 36tq at the wheels.
Well get out of the arm chair and get under that hood, we can talk it fixed...lol sorry ,,could resist..
The idea that short push rods "eating up" some of the lift, would not account for the 50hp that you cant find is not really accurate.
Lets take and assesment here.
1. you running on 89 octant gas
2. running at 12 deg adv timing.
3. possible valvetrain geometry isues
4. not getting all the lift out of your cam.
Forget about 50 hp, Im surprised your car is running well enough to pull on a dyno. .ALSO, with that much lift and spring pressure, ARE you still using the stock pushrods..you probly want to go to hardened...just a thought
Just check the stuff ,and do it right..
Not a sermon just a thought...
crazypete said:
The idea that short push rods "eating up" some of the lift, would not account for the 50hp that you cant find is not really accurate.
Lets take and assesment here.
1. you running on 89 octant gas
2. running at 12 deg adv timing.
3. possible valvetrain geometry isues
4. not getting all the lift out of your cam.
Forget about 50 hp, Im surprised your car is running well enough to pull on a dyno. .ALSO, with that much lift and spring pressure, ARE you still using the stock pushrods..you probly want to go to hardened...just a thought
Just check the stuff ,and do it right..
Not a sermon just a thought...
rd
Founding Member
There should be more in that combo.
Although old school carbed 302's were considered strong at 250 hp five years ago.
My carbed 82 runs high 12's etc, with iron Gt40's, an Edelbrock Performer rpm, a Holley 600, etc, and a C4. By the calculators, thats about 270hp at the wheels.
I have a 1988 Rhodes Lifters VVT270 cam and Rhodes lifters, with nearly 100K. Something like 464 lift.
I would go back and look at what you have. One item might be that the stock cam is just not enough for the heads now.
Keep at it, and it will get better.
Although old school carbed 302's were considered strong at 250 hp five years ago.
My carbed 82 runs high 12's etc, with iron Gt40's, an Edelbrock Performer rpm, a Holley 600, etc, and a C4. By the calculators, thats about 270hp at the wheels.
I have a 1988 Rhodes Lifters VVT270 cam and Rhodes lifters, with nearly 100K. Something like 464 lift.
I would go back and look at what you have. One item might be that the stock cam is just not enough for the heads now.
Keep at it, and it will get better.
795.0pacecar - There is an extremely small amount between the RPM and Performer intake. It is just the upper that is different. That intake is not holding him back.
I use stock pushrod length as told by Ed Curtis. They are "perfect". He has did cams so long and messed with blocks, I'm pretty sure he is accurate in what he says
Deck height (unless it has been decked, which needs to be told to Ed) varies little in reference to what length pushrod to get if the blocks haven't been tampered with. Just tell him the block and what you want, he will give you what you need.
I use stock pushrod length as told by Ed Curtis. They are "perfect". He has did cams so long and messed with blocks, I'm pretty sure he is accurate in what he says
Deck height (unless it has been decked, which needs to be told to Ed) varies little in reference to what length pushrod to get if the blocks haven't been tampered with. Just tell him the block and what you want, he will give you what you need.
MrKwik said:
Well, I said 400hp * .80 for drivetrain loss = about 320 . Then I did the "magazines lie" correction -20 hp = about 300 hp. Then I did the "I'm only running 12 degrees timing/87 ocane/carb not set perfectly" correction -20 = about 280.So I was expecting to see 275 or 280 realistically.
MrKwik said:
Yeah I asked him for a torque cam for monster torque cause thats what makes a car fun to drive. But I didnt really see it. I dont know. 308/.8 = 385.....385 ft lbs of flywheel torque aint all that bad.
MrKwik said:
I didnt want a huge intake. I wanted a nice intake but concentrate on air velocity and low-midband optimizations. That intake was my choice for a stock motor with a carb conversion. I think it's well matched to a 570 carb.
Would you say the eddie performer is running out of steam that early?
MrKwik said:
I base it on fulll throttle stumbling or little doof doof super rich sounds at idle really. The guage just always seems to agree with my other indicators so I continue to use it. It's the cyberdyne one.
sometimes not doing things right the first time..........causes you to have to go back and do it over. Don't let that stop you.
Yes, do a copmpression check;
Do a dynamic balance test (EEC self-test);
Do a leakdown test and listen in the intake and exhaust with a stethescope for leaking valves;
Put fresh plugs in, run it hard and shut down immediately - then poull and read all 8 plugs;
Yes, do a copmpression check;
Do a dynamic balance test (EEC self-test);
Do a leakdown test and listen in the intake and exhaust with a stethescope for leaking valves;
Put fresh plugs in, run it hard and shut down immediately - then poull and read all 8 plugs;
Ok, I just compression tested the motor.....about 160-165 on all cylinders. They held the pressure for a few minutes each. Valves are sealing. Actually....this is the exact same cylinder pressure I was seeing before with the stock heads. Shouldnt it be a little higher now with all this extra "power"?
Existing plugs looked real clean. No black soot or white deposits or oil.
Existing plugs looked real clean. No black soot or white deposits or oil.
you sure the dizzy is a good unit? Coil?
even with smoothing at 0 there is no way the graph should look like that.
Link to mine with smoothing set to 0.
http://members.cox.net/huddy31/cleanLX.jpg
No one thing is going to find 50 magic hp.
Put a decent intake on it, check plugs, wires, dizzy, coil... add timing... with a carb, shouldn't you be looking for 32* total at ~3000rpm rather than X* initial? Degree the cam, check pushrod length etc etc...
Wether you have a "dump truck" cam or not, it should be making more hp, more tq, and should not look like a rhictor(sp?) scale.
The thing that really stands out to me is, ed ground you a tq cam, and, the tq is not impressive at all.
Something is a-miss.
even with smoothing at 0 there is no way the graph should look like that.
Link to mine with smoothing set to 0.
http://members.cox.net/huddy31/cleanLX.jpg
No one thing is going to find 50 magic hp.
Put a decent intake on it, check plugs, wires, dizzy, coil... add timing... with a carb, shouldn't you be looking for 32* total at ~3000rpm rather than X* initial? Degree the cam, check pushrod length etc etc...
Wether you have a "dump truck" cam or not, it should be making more hp, more tq, and should not look like a rhictor(sp?) scale.
The thing that really stands out to me is, ed ground you a tq cam, and, the tq is not impressive at all.
Something is a-miss.
thumper460
Founding Member
You see what they all are saying... and there is a LOT of knowledge out there, and some killer links!!
In MHO.. if you came to my shop.. this is what would happen!
..Compression test.. 165# "IS".. high octane fuel requirements!!
..Run the engine and check when the ign timing is in at full advance ( vac off) and what timing is at idle ( ruff 700-850 rpm).
..Check the holley.. jetting/ power valves/ squirter/ secondary spring set up/ accel cam set up.
..Check the push rod geomerty. springs for coil bind and spring pressure for cam specs.
Remember there is NO eletronics doing all this for you, NO knock sensor/02 sensor ect.. and it is ALL up to the tune!!
Dizzy: set the dist for a 30* advance max from the mech. side of the dizzy. set the springs for the MAX advance in at 1800-2200 rpm! With timiming lite set the total advance in at 38* ( 30* out of dizzy mech advance and 8* buy turning the dist seting) for a total Ign advance in at 38* at 1800-2200 rpm!! adjust idle to the 700-850 rpm idle for the AOD and the 2500 stall! and recheck the "total" ign timing at rpm!! ( dist is now spun in for max power at lowest rpm)
Holley.. check jets.. check plug color! check power valve size..( check vac at idle and 2500 rpm) check accel squirter and pump cam size.. check and adjust the fuel bowl level. then bump jets up 2 sizes over stock. install 45 power valve.. 28 squirter.. aggressive accel pump cam..If vac secondary.. remove "check ball from dia. retainer, install purple spring. Make first run and adjust as necc.
Check vale springs for coil bind ( .030 MIM distance between coils valve full open) Check pring pressure at correct installed height and to cam specs. Check the push rod geomerty ( and NO that will not be 50 HP loss, some yes.. but not any huge or even big amount) Make any ajustments to correct any errors.
Setting the cam in at dot to dot is OK.. Ed would have advised if there was a need to move it around. The good thing about talking to the cam grinder is that they have control of the cam all the way thru the mfg.. and know where the specs are at any phase!! Cool
Now.. dizzy is set for inital run!!
Carb is set for inital run
Valve train is set or inspected for inital run..
This is a dyno "tune" and run.. not just a bolt it down and see what you have run!! With a carb set up this is the way.. and IF a shop does it.. the cost for thir time isnt cheap!! IF you can find a good Carb Dyno shop!! cool??
Me... your heads at 168 cc are too big for what you want..140-145 cc runners. Intake is wrong.. suggest Stealth by Weiand pulls from 0 to 6800 rpm. carb is too small ( 600 cfm min. with heads /cam/ ign mods)
Cam... ICL appears to be good making 165 lbs on comp test, the lift is aggressive but the duration is quites small for a crab. DONT go out and buy stuff.. use all the comments and links given and get your combo to work!! and as said above.. yeah they did make 400 hp from ported heads.. but there is years and years of technical experience making that happen and that is WHY it made the mag..
Sorry this is so long.. have fun!!
Just me..............................
Thumper
PS: there is a lot of assuming here.. wires/cap/fuel pressure ect is all set and in good working order..cool??
In MHO.. if you came to my shop.. this is what would happen!
..Compression test.. 165# "IS".. high octane fuel requirements!!
..Run the engine and check when the ign timing is in at full advance ( vac off) and what timing is at idle ( ruff 700-850 rpm).
..Check the holley.. jetting/ power valves/ squirter/ secondary spring set up/ accel cam set up.
..Check the push rod geomerty. springs for coil bind and spring pressure for cam specs.
Remember there is NO eletronics doing all this for you, NO knock sensor/02 sensor ect.. and it is ALL up to the tune!!
Dizzy: set the dist for a 30* advance max from the mech. side of the dizzy. set the springs for the MAX advance in at 1800-2200 rpm! With timiming lite set the total advance in at 38* ( 30* out of dizzy mech advance and 8* buy turning the dist seting) for a total Ign advance in at 38* at 1800-2200 rpm!! adjust idle to the 700-850 rpm idle for the AOD and the 2500 stall! and recheck the "total" ign timing at rpm!! ( dist is now spun in for max power at lowest rpm)
Holley.. check jets.. check plug color! check power valve size..( check vac at idle and 2500 rpm) check accel squirter and pump cam size.. check and adjust the fuel bowl level. then bump jets up 2 sizes over stock. install 45 power valve.. 28 squirter.. aggressive accel pump cam..If vac secondary.. remove "check ball from dia. retainer, install purple spring. Make first run and adjust as necc.
Check vale springs for coil bind ( .030 MIM distance between coils valve full open) Check pring pressure at correct installed height and to cam specs. Check the push rod geomerty ( and NO that will not be 50 HP loss, some yes.. but not any huge or even big amount) Make any ajustments to correct any errors.
Setting the cam in at dot to dot is OK.. Ed would have advised if there was a need to move it around. The good thing about talking to the cam grinder is that they have control of the cam all the way thru the mfg.. and know where the specs are at any phase!! Cool
Now.. dizzy is set for inital run!!
Carb is set for inital run
Valve train is set or inspected for inital run..
This is a dyno "tune" and run.. not just a bolt it down and see what you have run!! With a carb set up this is the way.. and IF a shop does it.. the cost for thir time isnt cheap!! IF you can find a good Carb Dyno shop!! cool??
Me... your heads at 168 cc are too big for what you want..140-145 cc runners. Intake is wrong.. suggest Stealth by Weiand pulls from 0 to 6800 rpm. carb is too small ( 600 cfm min. with heads /cam/ ign mods)
Cam... ICL appears to be good making 165 lbs on comp test, the lift is aggressive but the duration is quites small for a crab. DONT go out and buy stuff.. use all the comments and links given and get your combo to work!! and as said above.. yeah they did make 400 hp from ported heads.. but there is years and years of technical experience making that happen and that is WHY it made the mag..
Sorry this is so long.. have fun!!
Just me..............................
Thumper
PS: there is a lot of assuming here.. wires/cap/fuel pressure ect is all set and in good working order..cool??
Thanks for that Thumper, you're the man. Thanks everyone else for all the advice.
Wow...looks like I got a lot of work to do...tuning it in for high octane gas especially...
One last question though.... almost off the subject. But lets say I tuned it properly for it's max potential power....what kind of mpg should I be seeing? Right now, I am seeing atrocious mileage (13 combined) and its killing my love of the machine since I've been passing up opportunities for road trips and doing little more than locally ferrying myself around. My girlfriend's 4.10 geared 5.0 tbird is getting better mpg than my lightweight mustang. Is this a lost cause or is this also a tune issue?
The dizzy is a new accel adjustable unit and the cap is likewise new. New wires. Plugs are older but they all looked great when I checked em yesterday. Nice and clean. Side gapped, indexed. Carb is 28 shooter, stock pump cam, 6.5 power valve, 64/66 jets and enough idle screw to make the idle max rpms. Idle set at 1000 rpms to cover up the PS pump.
But with high octane, this will all change. I'll be tuning against detonation and hesitation.
Wow...looks like I got a lot of work to do...tuning it in for high octane gas especially...
One last question though.... almost off the subject. But lets say I tuned it properly for it's max potential power....what kind of mpg should I be seeing? Right now, I am seeing atrocious mileage (13 combined) and its killing my love of the machine since I've been passing up opportunities for road trips and doing little more than locally ferrying myself around. My girlfriend's 4.10 geared 5.0 tbird is getting better mpg than my lightweight mustang. Is this a lost cause or is this also a tune issue?
The dizzy is a new accel adjustable unit and the cap is likewise new. New wires. Plugs are older but they all looked great when I checked em yesterday. Nice and clean. Side gapped, indexed. Carb is 28 shooter, stock pump cam, 6.5 power valve, 64/66 jets and enough idle screw to make the idle max rpms. Idle set at 1000 rpms to cover up the PS pump.
But with high octane, this will all change. I'll be tuning against detonation and hesitation.
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