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Camshaft for 388 sbc, and 88mm Turbo

6K views 49 replies 8 participants last post by  HeavyChevyDeluxe 
#1 ·
Hello,
I need some advice for my new project 388sbc forged, full ported edelbrock aluminium heads, 8.2:1 Comp Ratio, 88mm turbonetics y2k ball bearing and like 10-15psi to reach 700hp at flywheel i actually have a crane-119661 but this is a Blower cam. So it can be hydraulic roller, or solid roller (if there's a real power increase with this one)

Thanks :thumbup:

Mauricio
 
#7 ·
That would be really nice, :evil::evil:

Where i can grind a custom cam for my aplication?, i send some mails to compcams, bulletcams, without answer.

Also i have to buy the new intake manifold, rails and injectors, need advice here too (single or dual plane) i have some 60lb/hr injectors, but i think i will need bigger ones
 
#8 · (Edited)
:welcome: Been a While, How did you do with the Supercharger on the SAND ? :thumbup:

First thing you need to remember is to mention in your posts that you do high altitude racing, sand runs "UP SIDES OF MOUTAINS" (and its not a groomed track) !!! LOL Its very important you state that or you could have someone recommending a cam they use in DEATH Valley thats below sea level !!!!LOL

With our language barrier "A groomed track is cleaned up and smoothed out " NO BUMPS OR BOULDERS "!!!:mwink:

My thoughts on boosted cams:
Supercharged engines have a shorter intake, longer exhaust, and wider (LCA) and are very easy to pick a cam for Turbo Charged engines are very complicated to pick a cam for!!

Before the turbo reaches speed to create good boost the engine behaves much like a low compression NA engine. This means to fill a cylinder at low compression and get exhaust at enough velocity to spin the turbo
would be a relatively close LCA. but once the turbos spinning fast enough to produce good boost the engine is acting like a regular mechanically driven blower engine and would run better with a wider LCA! LOL So at low RPM a close LCA and as higher PPMs come into play LCA needs to be wider!!! so there is a big compromise that needs to be deliberated ! If you choose one cam you lose here if you choose another cam you loose there!!!

A small turbo will spin up faster then a big turbo, which helps but is not good for supplying large amounts of air!! And is also complicated with high altitude running , And with you slowing and speeding up for obstacles (LIKE BOULDERS LOL) the turbo will spool down and up over and over fluctuating boost (maybe too much to keep boost at a beneficial level)!

That's why years ago I jumped to roots blowers, I do not like turbos for anything but full throttle drag runs!! The mechanically driven blower is still my choice (especially a roots like a GMC)because it is more constant in its boost production at any RPM and has big torque from idle to peek RPM!

I would suggest you call a very good cam grinder and tell them your driving conditions and have them with your help design a cam that meets your needs ! I am not qualified to Suggest a turbo cam for your type raceing and conditions ( I do not run turbos anymore or like them), And I have not kept up with them over the years> OH , I could web search and read and post crap from other peoples blogs or statements!! BUT I WOULD NOT BE ABLE TO STAND behind them !

Good Luck

Jester (Chris)
 
#10 ·
Jay Allen @ Camshaftinnovations.com Did a couple for me far a couple of fords (very good)

Lunati ground a couple of really good cams for me !

Harold Brookshire is good!!!!I have his old number 662-562-4933 Harold can help you out in the planing and development and get it ground!!

The other good people I know are dead and waiting for me LOL :thumbup:

Jester (Chris)
 
#13 ·
MY GOD, I feel terrible about my joke:( "The other good people I know are dead ....."
He was only a little older then I am:eek: He was a great man in the industry and life style! may he rest in peace ! He helped me design and grind quite a few cams over the years I'm so soory he is gone :( !!! Now I'm thinking of my own mortality :confused: its getting closer!! I was very ill since before Christmas and just started feeling better a short time ago ! I probably missed the thread on here or news report about his death ! Thank you for telling me!!

Jester (Chris)
 
#14 ·
Schneider Racing Cams was a great choice in the 60s and 70s they even sponsored me once but I haven't heard much about them for a while and Bullet has been mentioned and Crow cams was a good grinder haven't heard about them in quite a while! I used a lot of Mr. Horsepower , Clay Smith Cams Their custom grinds were one of the best!!!

Jester (Chris)
 
#17 ·
"I'll get a lot of GRUFF from some of the guys one here..."

Not from me, I feel the same way.

modern valvetrain parts and materials we have now means that you no longer have to be lashing the valves every week if running a street/strip or mid level bracket car hard, like the complaints from hotrodders of the 1960's and 70's. Now it is about twice a season that you have to check it, start of year and middle of year.
 
#21 ·
Vinnie, Chris, Eric, whomever,

What are the advantages/disadvantages of a square cam over a cam with 6-8 deg more exh duration than intake duration? Or vice versa? Do the benefits change depending on driving application or turbo size?


I've looked all over the web for answers to these questions and spoke to a couple of engine builders and I'm yet to come up with any consistency to the answers. I'm not expecting it here either, but maybe.

Thanks in advance and thought this info might help explain the grinds being recommended to the OP.
 
#22 · (Edited)
A dual pattern cam is made to pin point best flow, in ports and valves of different size and characteristics! look at the cylinder as a single flow one valve push system and the valve is small and the flow by that valve is slow you would create a cam lobe for that one valve so it would reach its best performance! then you have another cylinder just like it but a vacuum system with a bigger valve and you would have a different lobe design for that cylinder ! now put those 2 valves in a single cylinder that pulls in and pushes out and use those 2 lobe designs you created for best performance of each valve and you have a dual pattern cam! A cam designed for each valves individual need with a different lobe for best flow!

" Do the benefits change depending on driving application or turbo size?" Yes,
Tried to make that simple LOL :mwink::thumbup:There is no advantage or disadvantage it is your job to pick the best cam for your build !! whether a straight grind or dual grind Only the engine Knows what is best!!! If it runs better its an advantage , if it runs worse its a disadvantage !!!:eek:

Jester (Chris)
 
#23 ·
Its funny years ago when I was running in Class racing or pit crewing, the dual pattern cam was the hot choice because the old technology head flow and design was suspect in power loss because of the flow in the ports and we also used different ratio rockers on the exhaust to compensate for the small valves! And I still see people using dual pattern cams and high ratio rockers today, even though the new head technology is so much better with increased flow ,and better combustion chambers that a straight ground cam is a much better choice now!! The dual pattern cam now is more for fuel economy and emission control today, unless your still using old technology heads !

Unless you test different cams ( Flat , Roller, solid, hyd., Dual grind or straight ) and rockers and just settle on one cam that's suggested on here or anywhere else , You have no Idea what you lost or gained in performance!! and have no idea what to recommend to anyone else, Some of us on here over the years have run and swapped so many cams it is mind boggling and we tested different cams and rockers in the same engines to narrow down our choices ! even getting custom grounds and sending them back to be reground befor being satisfied!!

Vinnie could suggest a cam, I could suggest a cam, ericnova72 can suggest one , Etc Etc, and you would need to test all three to decide which is the best! Each cam suggested will probably run better then another in some area of the power curve that we think you will need with your build, BUT TILL EACH CAM IS TESTED WHEN THAT ENGINE IS BROKE IN AND RUNNING !! No one knows for sure what each cam would act like, I will admit most hobbyists do not have sponsors LOL or the money to test more then one suggested cam so they stab one in off some forum that was suggested AND THEN SUGGEST IT TO OTHERS ON FORUMS LIKE THIS AND GET MAD IF ANYONE DISAGREES LOL

In my opinion The only advantages of roller cams over flat tappets is No ZDDP, A higher lift at a lower duration and the valve stays open longer at the top of the lobe! And that is my line of decision (lift and duration) I do not fool around at ,choosing between a flat tappet or roller bellow a certain lift a flat tappet may be a much better choice then a roller and produce much more power but over that lift and duration the roller is better!! You will never know without testing both , They both have their advantages and disadvantages and the choice is in wghing the two!! Any person Making a statement that a roller always makes more power, or vice versa is CRAP!!! Each has its place in performance and power output depending on the build! And money should not be The deciding factor!

I will state emphatically that solids on a cam will always produce more HP and RPM then Hyd.s

Hydraulics were invented for pleasure driving ( they are quiet and need no adjustments till you hear them) and years ago adjustment checks during tuneups were needed on solids about every 20,000 miles!

This is not aimed at anyone in particular ! the use of "you" is PLURAL, and its just my thoughts that might be interesting to someone LOL

Jester (Chris)
 
#24 ·
Thanks Chris for sharing your experiences with us ( i like to read your posts, because i like to learn), it's true what you said about camshafts try and error and try different configurations to use the one better fits to your application, and i will do that if i live there (in USA), but i live too far away in South America, and get cams or any engine part to here is more than twice the price sometimes, plus waiting like 2 to 4 weeks to have them in my hands, that's why i'm need some help to pick a cam that fits well to my application.

Thanks :thumbup::thumbup:
 
#25 ·
Not everyone is in the position to test different cams usually its professional racers or a sponsored team that does that or a high priced performance blue printer! And being over seas makes it worse !!

I was sponsored by Crane in the early seventys and they ground a cam that I hated and I went back to my General Kenetics Cam LOL but the Crane name was still on my Gasser and they didn't care LOL!! But I told everyone in the pits "that General Kenetics was a better Grinder" LOL Valvoline sponsored me LOL but the oil used to sludg on my breathers so I ran Kendal (no sludge) !! It was funny I had Valvolines name on the car and a case of Kendal next to my car in the pits LOL I also had Napa on the car but got my parts at Groats Auto in Wyandotte Michican:thumbup:

Jester (Chris)
 
#26 · (Edited)
I just posted on another post , and thought it was worth mentioning to you! Its something not thought about much by the professionals that know because its an automatic thing we do, We set valve lash at the cam position when lifters are on the base circle of the lobe not at TDC crank position!! A lot of young or old hobbyists set lifter lash at TDC and every 90 degrees of crank rotation for each corresponding cylinder , and some set them 8 at a time at TDC then one turn on the crank and set the other 8 lifters ! But that is very wrong for many high output cams and can lose gobs of HP or cause damage!!! Because all cams are not ground where those TDC crank position marks correspond with the actual lash position of the valves so be VERY careful they are fine for hydraulics and for most stock solid-lifter cams, BUT!!! some cams have VERY long clearance ramps that are high, and at TDC crank position for any cylinder, both the intake and exhaust valve for that cylinder are still on their ramps (OPEN), NOT on the cam's base circle! Even some stock cams !!!! So make sure you find the position of your lifters on the base circle of your cam to do a lash setting!! and mark that position for each lifter on your DAMPER to make later adjustments easier! Your top dead center crank position will still be the same for setting your timing!! But your valve settings will not be at each pistons TDC position in the cylinder!


Jester (Chris)

I said this to my automotive studants years ago at class covering valve lash, and it turned into an uproar of everyone talking back and fourth and wondering if they adjusted their lifters right LOL Because they got their info out of a Chiltons or Motors book on how to set their valves LOL and your Manuals do not take into consideration "HIGH PERFORMANCE CAM GRINDS" Not even most Chevy manuals!!! They do not even cover their own Cams like the 30 - 30!!
 
#28 ·
Ok, heres Lunati recommendation: (Hydraulic Roller)

The cam I recommend is a custom grind .900" small base circle, grind #
012-62703-62803-115+3. The cam is 231/235 @ .050, the lift is .536/.543,
and it is cut on a 115 LSA with a 112 intake centerline


Colt Cams answer this also:

Sorry we are unable to help you out with this
Thanks
 
#29 ·
Note to Chris: Ive adjusted valves like that (2 x 360º rotations) since I was 19. You get a feel on the feeler gauge,,, I also check a couple rotations.

TJ,you will be in the ball park with these cams as they are similar.
Noting what Chris said about cams;they create a personality in the engine. That personality has to match the driver. Also like Chris says; dyno figures do not make the fastest race cars,,, go back to what I said, the personalities have to match the driver.
 
#30 · (Edited)
Vinnie, I bet you check your valves hot and running too:thumbup: , I was not aiming that post at people that Know it is natural and ingrained in us, we do not even think about it, its like Breathing LOL , We find out the exact closing point of our valves and adjust accordingly!

I aimed it Just to those that do not Know!!

The 30- 30 , LT1, etc, cams were really trick for the racers that knew the procedure and would tell no one, and would get the edge over the racers that did not know because their lifter lash was set right and hot and running!

Through the years many people came and told me that when they adjust their hydraulic or solid lifters cold at #1TDC when both # 1 valves are closed (like the books say) they are set fine, but then noisy when running or complain about lost power, they recheck them at #1TDC and they are still fine 3/4 turn or the right solid lash !! So I check it out Hot and running and find when they adjusted both #1 valves at #1 TDC like in the books both #1 valves were actually open and when closed were way after #1 TDC and the lashes were loose, so I would set them hot and running readjust and had to loosen or tighten the lifter lash a lot depending on the cam grind!!!

Can you just imagine how many young people or unknowing come on here and adjust their valves by factory stock instructions given to them on these threads and how much power they are losing, because their cams closing point of the valves at #1s TDC are different and still are actually open.


Basic adjustment for Chevy small block solid and hydraulic cams in the books look like this:
With #1 piston at TDC, both number one valves are shut.
Adjust the #1 exhaust valve
Adjust the #1 intake valve
Adjust the #3 exhaust valve
Adjust the #5 intake valve
Adjust the #7 intake valve
Adjust the #2 intake valve
Adjust the #4 exhaust valve
Adjust the #8 exhaust valve
Now rotate the engine 360 degrees. The mark on the balancer should be back at the TDC mark. Keep in mind that this is not the TDC where #1 would be firing! It's where #6 would fire.
Adjust the #3 intake valve
Adjust the #5 exhaust valve
Adjust the #7 exhaust valve
Adjust the #2 exhaust valve
Adjust the #4 intake valve
Adjust the #6 exhaust valve
Adjust the #6 intake valve
Adjust the #8 intake valve

High output solid or hydraulic cams like the 30-30 or others adjustments: At top dead center both #1 intake and #1 exhaust valves are open! NOT closed !!
So for these type cams:
With #1 piston at TDC You adjust #8 Ex, and #2 Int - Not #1 ex. or #1 int. then turn crank 90 degrees at a time and set these!
90 deg. - 4E, 1I
180 deg. - 3E, 8I
270 deg. - 6E, 4I
0 - 5E, 3I
90 deg. - 7E, 6I
180 deg. - 2E, 5I
270 deg. - 1E, 7I
and on some cams the degree to set valves for each cylinder at their TDC may not be 90* it may very!

That's what I was trying to warn unknowing people about! Not the procedure just that the adjustment valve order in the procedure changes with different cams in the same engine If you adjust some cams like most books tell people to do, thinking when #1 piston is at #1 top dead center both #1 valves can be adjusted they will be way off . When using one cam at #1 TDC both #1 valves are closed and are adjusted, and then swap cams and at #1 TDC #8ex. and #2 int. will be the ones closed and you adjust Them.

I hope I wrote that so its not confusing ?? And in order to check to make sure your settings are right ALWAYS do a hot and running valve adjustment! it seems like most enthusiasts do not set hot and running because its messy LOL and rely on a cold setting even though it is a very important step in proper tuning! And will set your valves precisely where they should be!

Jester, (Chris)
 
#31 ·
Chris: rofl,I remember the first time adjusting solids while engine was running;
I had the old style "straight gauges that only go to .020" so I had to stack 2 blades (tried to use 3 blades so I could just add the .oo2 blade for the exhaust valves)
I was very slow so I got a lot of oil,,,,everywhere!
I flipped over the cover and pushed the plug wires onto the headers,
I didnt have a helper.

1 qt of oil
1 plug wire and I was done in 2 plus hours,NOT including clean up of engine bay aand washing and waxing car,,,
I did manage to get the points wet when I washed the engine bay

TOOK ALL DAY!!!
my hands hurt from holding the rockers while adjusting the nut,,,Im sure youve done that style by putting reverse pressure on the rockers so you can feel the gap clicking?

funny memories,thanks Chris
 
#38 ·
LOL , My first adjustments were in a 50 ford flat head LOL You have no IDEA LOL My second was on an Arden headed cement mixer truck! The worst was on the 426 Max wedges Cross ram engines To pull the valve covers you had to pull the intakes and then put them back on to do a running hot setting and then pull the intakes again put the valve covers back on and then replace the induction system again :sweat: Man I hated those LOL!!

Jester (Chris)
http://www.hotrodders.com/forum/attachment.php?attachmentid=222913&stc=1&d=1432245979
 

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#36 · (Edited)
Its funny reading these because some cams adjust "when exhaust valve just reaches fully open", then you set the intake, some when its at 1/4 lift some at 1/2 lift Etc Etc It depends on the cam ?? Its really pretty simple Its when any lifter is fully on the heal of the lobe and the valve is closed !!! Just find that point and set the valve, that's true with every cam ! Find that point during assembly and write the degrees down for that particular valve when fully closed and the lifter is on the heal and set your valves at exactly those degrees on your degree tape before top dead center or after top dead center!! its not supposed to be easy, just close, or fast it needs to be precise ! I have my ways of blue printing and I give each valves setting precise degree points to the owner with the engine:mwink: everyone's different I guess Stay with what works for you :thumbup:

When all of you use a degree wheel do you just check #1 cylinders TDC and valves opening and closing points on the wheel to see if they check out or do you check all cylinders with the degree wheel???

I check each cylinder at its TDC and write down its valves opening and closing points and full lift points and its valve setting points.

Jester (Chris)
 
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