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FE Power Forums => FE Technical Forum => Topic started by: gregaba on December 12, 2020, 06:50:18 PM

Title: Comp Cams 930-16 pressure
Post by: gregaba on December 12, 2020, 06:50:18 PM

Ordered a set of valve springs from Summit last year for my 428 with solid lifter flat tappet cam with .620 lift.
Summit recommended the 930-16 so I ordered them.
Last month I called Comp cams and they said they would be fine with my cam.
I went to Arlington to pick up my balanced assembly and I took the valve springs with me to let Charles measure them because I thought they might be to stiff for my build.
Here is what they measured
1.950     140#
1.900      150#
1.850      170 #
1.800      180#
1.780      190#
What is the opinions of everyone on this spring set up.
Thanks
Greg

Title: Re: Comp Cams 930-16 pressure
Post by: blykins on December 12, 2020, 07:08:34 PM

What’s your install height and which cam is it?  140 lbs seat is a lot for regular solid flat tappet.

Title: Re: Comp Cams 930-16 pressure
Post by: gregaba on December 13, 2020, 11:17:25 AM

Hi brent
Not going to use these as I will use the ones on the TFS heads I am going to use.
I bought these for a set of C2 heads I was going to use before I decided to buy a set of the TFS's.
I was just wondering about the spring pressure's on these as they were recommended by both Summit and Comp for my cam.
They both said these would be good for a cam with .620 lift. I did tell them it was for a flat tappet and not a roller.
Maybe they need to update their computer.
I wanted to post these numbers for anyone thinking of using them in a build.
Greg

Title: Re: Comp Cams 930-16 pressure
Post by: blykins on December 13, 2020, 11:39:08 AM

Quote from: gregaba on December 13, 2020, 11:17:25 AM

Hi brent
Not going to use these as I will use the ones on the TFS heads I am going to use.
I bought these for a set of C2 heads I was going to use before I decided to buy a set of the TFS's.
I was just wondering about the spring pressure's on these as they were recommended by both Summit and Comp for my cam.
They both said these would be good for a cam with .620 lift. I did tell them it was for a flat tappet and not a roller.
Maybe they need to update their computer.
I wanted to post these numbers for anyone thinking of using them in a build.
Greg

140 lbs seat is pretty stout for a flat tappet.  I've ran more than that, but they have been pretty aggressive, higher rpm camshafts. 

The issue with Comp or Summit either one making spring recommendations without knowing the install height ,valve weight, or anything else really just rubs me the wrong way. 

Title: Re: Comp Cams 930-16 pressure
Post by: 1967 XR7 GT on December 13, 2020, 09:04:42 PM

I had looked up the 930's before when I was thinking of using them.
The Specs say Installed Height @ 1.900

Height   Loads 1.950    135 1.900    153 1.330    358 1.300    365

Coil Bind   1.160

Title: Re: Comp Cams 930-16 pressure
Post by: manofmerc on December 15, 2020, 03:31:23 AM

Lunati has a similar spring 73121 I have used in my 460 bracket car as well as my edelbrock equipped 427 comet .These are a solid flat tappet spring.Similar specs 140@1.940 .Open specs are 402@1.250 .I have a spring checker and that is pretty much what they are .I haven't had any cam lifter issues with these springs .I use vr1 motor oil .I imagine they are the same spring as comps.They hold up pretty good in my .600 lift engine .Same story on the comet and it uses dumbbell lifters so no oil going to the lifter just what gets slung around .If one wanted less seat pressure just increase your installed height .

Title: Re: Comp Cams 930-16 pressure
Post by: gregaba on December 15, 2020, 10:13:29 AM

I just though that with I am using the car for these would be a little stiff. It will be a daily driver with maybe 6 or 8 trips to the strip a year. I am going to set my rev limiter at 6800 even though the cam will rev a lot more then that.
I know I am overly concerned with the spring pressures with the aluminum heads. I would have no problems running these springs with cast iron heads.
I am also concerned with the cam issues other people have had.
With this in mind I have a 40 year old set old springs from a 390 that I will use for break in. They should be good enough for 3000 rpm for 30 minutes
Never had a cam issue but I don't want one now.
Greg

Title: Re: Comp Cams 930-16 pressure
Post by: blykins on December 15, 2020, 10:22:36 AM

Quote from: gregaba on December 15, 2020, 10:13:29 AM

I just though that with I am using the car for these would be a little stiff. It will be a daily driver with maybe 6 or 8 trips to the strip a year. I am going to set my rev limiter at 6800 even though the cam will rev a lot more then that.
I know I am overly concerned with the spring pressures with the aluminum heads. I would have no problems running these springs with cast iron heads.
I am also concerned with the cam issues other people have had.
With this in mind I have a 40 year old set old springs from a 390 that I will use for break in. They should be good enough for 3000 rpm for 30 minutes
Never had a cam issue but I don't want one now.
Greg

Greg,

You would not have to worry about those springs on an aluminum head and that's not the issue that raises a flag in my mind.  FWIW, you can run up to 600 lbs open pressure on an aluminum head and you're about 7 miles away from 600 lbs with those springs.

However, the issue is that they may be too stout for the camshaft.  140 lbs seat is starting to ride the fence on too much spring pressure for a street camshaft.  With that being said, if you could give the cam specs and engine specs, I can tell you how high the cam will go and if the spring pressures are warranted.   Keep in mind that we really don't judge how aggressive/lazy a cam is by looking at the lift by itself, nor does that really play into how much spring pressure is needed. 

I run 160-170 lbs seat and over 400 lbs open on solid flat tappets, but they require special oiling lifters and other options.

Title: Re: Comp Cams 930-16 pressure
Post by: gregaba on December 15, 2020, 11:10:31 AM

Please disregard this message and read the next one. For some reason this posted half way though.
Greg

Title: Re: Comp Cams 930-16 pressure
Post by: gregaba on December 15, 2020, 11:28:52 AM

Yes that was my main concern.
I will give you the specs on the engine. I am hoping to make from 425 to 450 HP with it.
Engine block is blueprinted with deck at 10.155 and bore is 4.164.The cam and mains were honed for straightness and I had the lifter bores honed to clean them up. Screw in plugs in all the oil galleys.Cylinder bores were camfered and we clearanced the rear mail for  the windage tray mounting. 
Assembly was balanced to 2 grams with the rattler balancer installed.
Scat H beam rods part number 66490. Be 563.2 SE 252.1
Part#  66490.
Auto tech forged pistons Part# 1021059.
695.3 grams.
I will be using the TFS heads COO as soon as I build up my bank account some more.
Here are the cam specs. I know it is the wrong cam for what I am going to use the car for but I will run it far a few months and change it out for a more streetable cam but I want to have some fun with it for now.
Solid lifter Comp part# 33-000-5
Gross lift .614
Duration @.050 272 intake and exhaust.
Valve timing@ .050
Open
Int: 34  Ex 68
Close    ink   58  Ex 24
102 degree centerline.
Mushroom lifters NAPA part# 213-1656
I Have the FE Power intake adapter and a TFS 351C single intake and will be running a 1050 Carb or a EFI system. Haven't decided yet.
Also have the FE Power timing cover with adjustable timing gear for the expected cam change.
I have a 6R80 and will run a 3800 to 4000 lock up converter with a 444 Detroit locker.
The car weighs 3380 lbs now without engine, trans, insulation heater etc.as it was a striped down race car from birth. 63 Galaxie 2 Dr. sedan.
If you need more info just let me know, I am sure I forgot something.
Greg

Title: Re: Comp Cams 930-16 pressure
Post by: blykins on December 15, 2020, 12:30:59 PM

Well, that's a lot more cam than what I thought you had.   You need the valve spring pressure because the TFS heads will let it take advantage of the duration.   If it were mine, I'd probably run a hair more spring pressure than you have, but also keep in mind that the valve springs that come on the hydraulic roller TFS heads will have approximately the same spring pressure that you would have with the 930-16 springs, but they will be better quality springs/retainers than what you have. 

I'm not sure if Napa lifters will make it.  If you can give me the lobe numbers at the top of the cam card I will let you know.

Title: Re: Comp Cams 930-16 pressure
Post by: gregaba on December 15, 2020, 01:08:15 PM

Hi Brent
I could not find the lobe info on the card so I took some pictures of the cam and cam card.
If you don't think the NAPA lifters will work then give me a brand and as soon as I build up some money I will order a set.
Thanks
Greg

Title: Re: Comp Cams 930-16 pressure
Post by: blykins on December 15, 2020, 01:15:29 PM

Ahhh, it's one of those cams. 

You should be fine with what you have, springs included.  It's a big cam, but it's a real lazy cam. 

BTW, when you're dealing with spring pressures like that, take the inner springs out for break-in. 

Title: Re: Comp Cams 930-16 pressure
Post by: gregaba on December 15, 2020, 01:19:22 PM

Thanks for the advice.
I plan on running it for about 6 months and then I will order a roller that will work with my combo from you.
I just want it to live for 6 months as is.
Greg