need gudiance on cam change

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need gudiance on cam change

Post  70429scj on December 20th 2015, 6:44 pm

well my new engine plan for my thunderbird went out the window along with my budget. here is what I have left to try to upgrade  408w probe rotating assembly good crank h beam rods forged pistons 22cc dish yuck heads are victor jr that have been ported and polished by kieth craft ford racing roller rockers super victor intake 950 quickfuel custom built hooker 1 7/8 headers msd ignition evac system strip car only car runs on pump gas weight is 3300 pds roller c4 with reverse valvebody and pro tree transbrake 4000 stall converter 4.57 gears car has run the best of 6.67 at 103 normally runs in the mid 70s in the heat. guessing the motor makes a honest 540 at the flywheel. forgot to mention 88 t-bird on a 10.5 tire run baseline upper relocator kit double adjustable lowers from autoweld car goes straight and is consistent not so for the driver. when I had the heads done I didn't change the cam and basically the car picked up nothing no et no mph I am smallblock illeterit last one I owned was a 70 clevlend that I drove to high school. I cant afford to change the pistons but would like to change the cam here are the current specs comp 31-641-5 solid lifter lobe sep 106 centerline 106 duration at 50 intake 265 exh 276 lift intake .600 exh.593 intake lobe lift .376 exh.371 exh closes at 51 atdc opens at 83 bbdc intake opens at 44 btdc closes at 76 abdc let me know if I missed anything I did mill the heads .030 when it was apart so cc should by about 55cc. I know this is not the ideal compression ratio but its what I have to work with. should be 10.25 compression head flow numbers would prefer to stay with solid mechanical lifter cam
int.100-74 .200-133 .300-193 .400-246 .500-283 .550-301 .600-310 .650-314 .700-319 .750-321
exh.100-54 .200-108 .300-154 .400-183 .500-187 .550-191 .600-192 .650-192 .700-193 .750-194
not being a flow number jockey I belive the heads will support 600hp pretty easy not saying we can get there with this compression thanks for the help in advance guys I know this is not ideal but I cant justify tearing down a motor that has less than 30 passes on it . just thought of this if anyone needs this motor and has a big block to trade I might rather do that.
Thanks,
Steve
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Re: need gudiance on cam change

Post  rmcomprandy on December 27th 2015, 11:51 pm

70429scj wrote:well my new engine plan for my thunderbird went out the window along with my budget. here is what I have left to try to upgrade  408w probe rotating assembly good crank h beam rods forged pistons 22cc dish yuck heads are victor jr that have been ported and polished by kieth craft ford racing roller rockers super victor intake 950 quickfuel custom built hooker 1 7/8 headers msd ignition evac system strip car only car runs on pump gas weight is 3300 pds roller c4 with reverse valvebody and pro tree transbrake 4000 stall converter 4.57 gears car has run the best of 6.67 at 103 normally runs in the mid 70s in the heat. guessing the motor makes a honest 540 at the flywheel. forgot to mention 88 t-bird on a 10.5 tire run baseline upper relocator kit double adjustable lowers from autoweld car goes straight and is consistent not so for the driver. when I had the heads done I didn't change the cam and basically the car picked up nothing no et no mph I am smallblock illeterit last one I owned was a 70 clevlend that I drove to high school. I cant afford to change the pistons but would like to change the cam here are the current specs comp 31-641-5 solid lifter lobe sep 106 centerline 106 duration at 50 intake 265 exh 276 lift intake .600 exh.593 intake lobe lift .376 exh.371 exh closes at 51 atdc opens at 83 bbdc intake opens at 44 btdc closes at 76 abdc let me know if I missed anything I did mill the heads .030 when it was apart so cc should by about 55cc. I know this is not the ideal compression ratio but its what I have to work with. should be 10.25 compression head flow numbers would prefer to stay with solid mechanical lifter cam
int.100-74 .200-133 .300-193 .400-246 .500-283 .550-301 .600-310 .650-314 .700-319 .750-321
exh.100-54 .200-108 .300-154 .400-183 .500-187 .550-191 .600-192 .650-192 .700-193 .750-194
not being a flow number jockey I believe the heads will support 600hp pretty easy not saying we can get there with this compression thanks for the help in advance guys I know this is not ideal but I cant justify tearing down a motor that has less than 30 passes on it . just thought of this if anyone needs this motor and has a big block to trade I might rather do that.
Thanks,
Steve

Get something custom ground and use more rocker arm ratio if it is needed to get the net intake valve lift near .700" with valve springs to match.

This is the classic example of a better flowing head meaning nothing because more than you need will not be of any advantage; it actually may become a disadvantage if the velocity suffers a lot.

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Re: need gudiance on cam change

Post  738drvr on December 30th 2015, 5:25 pm

Jones Cams, Straub cams, Mark at Bullet cams.

Do it right once and never think about it again.
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Re: need gudiance on cam change

Post  supervel45 on December 30th 2015, 7:20 pm

Being it's a 408W If I wanted a custom cam I would likely go with someone who put that engine in the winners circle at the 2015 EMC Competition. RMCompetition

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Re: need gudiance on cam change

Post  738drvr on December 30th 2015, 7:31 pm

Randy's good but there's no comparison to Mike Jones or Chris Straub.

None.
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Re: need gudiance on cam change

Post  supervel45 on December 30th 2015, 8:15 pm

How did Straubs 611 dyno pull work out?

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Re: need gudiance on cam change

Post  738drvr on December 31st 2015, 12:47 am

Call him and ask.
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Re: need gudiance on cam change

Post  FalconEh on December 31st 2015, 1:43 am

supervel45 wrote:Being it's a 408W If I wanted a custom cam I would likely go with someone who put that engine in the winners circle at the 2015 EMC Competition. RMCompetition

X2

738drvr wrote:Randy's good but there's no comparison to Mike Jones or Chris Straub.

None.

I think there is a point where our opinions become unjustified through whatever bias we may hold, although I do not discredit ANY of those mentioned, I believe Randy was in this comment.
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Re: need gudiance on cam change

Post  738drvr on December 31st 2015, 8:22 am

Randy is a very good engine builder. I did not intend to bash Randy. I have built a handful of engines. If my engines work good and "run the number" does that mean I know what Randy does about engine building? Of course not. Let the specialists with the knowledge, experience and know-how have their place whether it be camshafts, converters, heads, engine building or ?. Randy probably understands camshafts about as well as any engine builder. Does that mean he knows what people like Jones, Straub and others like them do? No, he doesn't. Why do the cam specific people share story after story over the phone, on forums, at tech seminars, etc... about customers who tried cam after cam, often times after listening to the guy that was building the engine, try a specific cam custom ground for their specific application and pick up e.t. and speed or h.p. on the dyno? It's not all "fluff" or propaganda. I personally know some great engine builders who spec. their own camshafts. These same guys sometimes pick up the phone and call the specialists with questions. Why is that?The guys that do camshafts for a living ended up doing them for a reason. They're really good at it. Every engine is different. Every vehicle is different. So, to get the most, every camshaft should be slightly different. That's what specialists do. That's why many of the best race teams in the world use specialists. Why shouldn't the little guy like you and I do the same? Camshafts are the "brains" of the engine. This is one area where being close enough results in leaving power on the table. If guys will spend thousands on a new set of heads, why not spend a couple hundred extra and get a custom camshaft? Seems obvious to me.
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Re: need gudiance on cam change

Post  whitefield on December 31st 2015, 8:23 am

In my opinion stall speed needs to be higher and rear gear ratio 4:11 to 4:30 .
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Re: need gudiance on cam change

Post  whitefield on December 31st 2015, 1:31 pm

Also what is your starting line rpm, shift rpm ,and crossing the line rpm?


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Re: need gudiance on cam change

Post  rmcomprandy on December 31st 2015, 11:55 pm

738drvr wrote:Randy is a very good engine builder.  I did not intend to bash Randy. I have built a handful of engines. If my engines work good and "run the number" does that mean I know what Randy does about engine building? Of course not. Let the specialists with the knowledge, experience and know-how have their place whether it be camshafts, converters, heads, engine building or ?. Randy probably understands camshafts about as well as any engine builder. Does that mean he knows what people like Jones, Straub and others like them do? No, he doesn't. Why do the cam specific people share story after story over the phone, on forums, at tech seminars, etc... about customers who tried cam after cam, often times after listening to the guy that was building the engine, try a specific cam custom ground for their specific application and pick up e.t. and speed or h.p. on the dyno? It's not all "fluff" or propaganda. I personally know some great engine builders who spec. their own camshafts. These same guys sometimes pick up the phone and call the specialists with questions. Why is that?The guys that do camshafts for a living ended up doing them for a reason. They're really good at it. Every engine is different. Every vehicle is different. So, to get the most, every camshaft should be slightly different. That's what specialists do. That's why many of the best race teams in the world use specialists. Why shouldn't the little guy like you and I do the same? Camshafts are the "brains" of the engine. This is one area where being close enough results in leaving power on the table. If guys will spend thousands on a new set of heads, why not spend a couple hundred extra and get a custom camshaft? Seems obvious to me.

Just for communicated knowledge ... I do supply custom camshafts for engine platforms I know well as part of my living.  AND, some of the major camshaft companies HAVE called me for information.

That being said ... do whatever you want to do and get your recommendations from wherever you wish.  "Doing it right" is all about that person's opinion. Opinions are like ... well, everybody has one.

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rpm

Post  70429scj on January 20th 2016, 4:43 pm

usually leave the line on footbrake at 3200 shift right at 7000 crosses at 7200 if I remember. not sure why the gear change am I overlooking something here. Guys did not mean to start a pissing match I was looking for some help with this small block cause I have no idea what to do. just to point out my expertize is with the 385 if I claim to have any as a example my street car with a 466 c6 and weighing 600 more pounds is within a 10th of these ets with a m/t pro tire and 96 octane so I need to step up the supposed race cars 408w motor cause a 385 is outta the budget this year unless someone wants to buy this 408w. Randy are we talking solid roller? thanks for the advice.
Steve
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Re: need gudiance on cam change

Post  rmcomprandy on January 20th 2016, 7:35 pm

Personally, I would start with what you have; advance the cam 2 to 4 more crankshaft degrees than where it is at now, put a higher ratio rocker arm and open the lash about .005" on the intake side.
Be sure the valve springs can handle the extra valve lift.

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Re: need gudiance on cam change

Post  supervel45 on January 20th 2016, 8:25 pm

Get a set of flat top pistons and try to get the exhaust ports close to 220cfm if possible is what I would do. Short of all that, what Randy said.

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Re: need gudiance on cam change

Post  whitefield on January 20th 2016, 10:25 pm

70429scj wrote:usually leave the line on footbrake at 3200 shift right at 7000 crosses at 7200 if I remember. not sure why the gear change am I overlooking something here. Guys did not mean to start a pissing match I was looking for some help with this small block cause I have no idea what to do. just to point out my expertize is with the 385 if I claim to have any as a example my street car with a 466 c6 and weighing 600 more pounds is within a 10th of these ets with a m/t pro tire and 96 octane so I need to step up the supposed race cars 408w motor cause a 385 is outta the budget this year unless someone wants to buy this 408w. Randy are we talking solid roller? thanks for the advice.
Steve    

I think the gear is to much and not making the engine work . Stall speed is to low and killing the power before the engine can start making power.. Intake is to big and killing torque .

Now here is the reason. Behind my  thinking !

I have the mustang in the avatar before I lightened it it weighed 3170 lbs.
393 10.5 :1 compression  4:11 gear drag radials and a 4800 9.5 stall went 6.80 at 104 mph 1.44 60 on drag radials cam at this time was a  .672 intake 690 exhaust  duration @.050  intake 255 exhaust 272 107 lobe sep.
950 CFM. AFR 205 heads.
I bought super Vic intake car slowed down , I changed to a 3.73 gear car ran the same , changed cam shafts to find out the above cam was the better cam . Changed  converters 5 times  and settled on a 8 5000 which gave me my best 60 ft with the last cam  that was in it. So when it was all said and done before I sold the engine the car had a 1.42 60 ft and a 102 mph. With a 6.80 1/8. The cam was  690 lift  261 intake 268 exhaust duration @ .050 106 lobe sep.  all cams were solid roller and all parts were bought new . Carbs were also,changed from  a proform 750 race carb, to 860 pro system and then 950 quick fuel. All ran close  . So I figure that the engine was making all she was going to make. I also changed mufflers and it had 1 3/4 bbk long tube headers with 3" exhaust. C4 transmission . I know the weight is off 200 lbs !  Car made 380 RWHP through 5500 stall at the time of Dyno.
Now if the changes Randy recommend and  I feel the ones I have purposed don't make any changes then you are in the same boat I was in.

I am just trying to help and these are just my opinions. And experience .
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