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Old 07-24-2013, 03:50 PM   #21
augiedoggy
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Originally Posted by REELAV8R View Post
Not sure. I used a 4.1 gasket bore also.

That 301A7 cam drops it down quite a bit into a usable range with some cushion for higher engine temps. Looks almost like an L-82 cam. Should get the job done with a 9.82 CR.
I found it... I had 6 listed for advance insted of 4...

I am now considering two more reasonable priced cams that should also work well and give me more usable torque.

http://www.competitionproducts.com/searchprods.asp

Also the 111221-10 Howard's cam..

http://www.howardscams.com/index.php/chevrolet-v8/chevrolet-v8-262-400-non-oe-hydraulic-roller-1957-1996
These both bring my DCR down with higher durations but there has to be a trade off? I'm assuming these will bring my HP down into 325-340 range?
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Old 07-24-2013, 05:02 PM   #22
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Can't see this cam. For these links if you just right click on the address bar then copy and paste it here then it turns into a hyperlink and people can just click on it to see the page.
I like the Howards cam too. It gives you a 7.81:1 DCR at your altitude. I like it a little better due to the 110 LSA vs the 114 LSA.
With your .049 quench this engine will be somewhat more detonation prone than one with a .040 quench. Make sure the cooling is up to par for this you'll need to keep it fairly cool to make things work well. You still may have to pull timing on hot days, hard to say.

Your torque converter of 2000 rpm stall will likely work ok. You should call a torque converter company and see what they would recommend. My guess would be more in the 2600-2800 range.

This kind of cam will have a little less torque than one of shorter duration, but you gotta do what's necessary to get the DCR down a bit, it will however extend the operating range of the engine from 5000 to something higher. The Howards cam advertises 1500 to 5600. So your HP will probably remain roughly the same just developed at a higher RPM. This actually may work fine with the 3.08 and TH350 combo as now you can shift at a higher RPM and not drop out of the operating range of the cam. Assuming that the heads, exhaust or intake are not a restriction to flow at that RPM.
A higher duration cam develops less torque for a given CR, displacement etc, so it may be lazier off the bottom (relative to what you had before) but pull longer up top.
I added a B&M Th350 with a shift kit to my combo (also 3.08 rear) and it really woke up the shifting. It's like speed shifting with a manual. It chirps on 1st to 2nd shift with almost no delay between gears. You can buy just the shift kit.

Last edited by REELAV8R; 07-24-2013 at 05:11 PM.
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Old 07-24-2013, 05:24 PM   #23
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Can't see this cam. For these links if you just right click on the address bar then copy and paste it here then it turns into a hyperlink and people can just click on it to see the page.
I like the Howards cam too. It gives you a 7.81:1 DCR at your altitude. I like it a little better due to the 110 LSA vs the 114 LSA.
With your .049 quench this engine will be somewhat more detonation prone than one with a .040 quench. Make sure the cooling is up to par for this you'll need to keep it fairly cool to make things work well. You still may have to pull timing on hot days, hard to say.

Your torque converter of 2000 rpm stall will likely work ok. You should call a torque converter company and see what they would recommend. My guess would be more in the 2600-2800 range.

This kind of cam will have a little less torque than one of shorter duration, but you gotta do what's necessary to get the DCR down a bit, it will however extend the operating range of the engine from 5000 to something higher. The Howards cam advertises 1500 to 5600. So your HP will probably remain roughly the same just developed at a higher RPM. This actually may work fine with the 3.08 and TH350 combo as now you can shift at a higher RPM and not drop out of the operating range of the cam. Assuming that the heads, exhaust or intake are not a restriction to flow at that RPM.
A higher duration cam develops less torque for a given CR, displacement etc, so it may be lazier off the bottom (relative to what you had before) but pull longer up top.
I added a B&M Th350 with a shift kit to my combo (also 3.08 rear) and it really woke up the shifting. It's like speed shifting with a manual. It chirps on 1st to 2nd shift with almost no delay between gears. You can buy just the shift kit.
Sorry its the elgin E922k cam.... the sell the whole kit including lifters valve springs locks and seals with the lube for $146 shipped! This is the same cam as the summit 1103 and the lunatic 10001lk just different name on the box it seems

Elgin, Hydraulic Flat Tappet Complete Cam Kit, Chev SB Chev SB Lift: .443/.465 Duration: 288/298 Duration @ .050": 214/224 Lobe Separation: 112 LC Mild idle. Good low end torque. Stock converter OK. In Stock
Btw
I did copy and paste link but that doesn't seem to work in mobile mode on andriod devices....
I currently have obx side pipes and 2 1/4 sweet thunder chambered muffler for the iron eagle 180 heads so I'm thinking it will be able to breath well...
The elgin cam is a bit more conservative that the Howard's cam but from the info I found on the web its an old but tried and true combo...
I may convert to dual electric fans as I found a setup from a Chevy truck that will fit nice. Haven't decided yet.
Either way I'm nervous about the lifters because even though they were labeled in order in the box by the guy I bought them from because he pulled them from the block I bought so they wouldn't fall out in transit I don't want to chance if they got mixed up

Last edited by augiedoggy; 07-24-2013 at 05:39 PM.
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Old 07-24-2013, 05:45 PM   #24
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I do currently have the double 1.437 springs that came with my iron eagle heads but I don't know if going to the milder "z28" springs supplied with the elgin kit would be easier on the cam lobes? If I can get away with it I'd just order the summit kit. I do find it funny that summit and lunati have different operating ranges for the same cam.... lunati rates their advertised duration differently so they are usually 6-8 off other manufactuers I read.

The crane 100052 at 272 adv 454 lift and 110 lsa 1600-5500seems like a good choice I can get with lifter cheap too (half summits price on eBay).... my iron eagles actually flow better on the exhaust side than intake so I don't really thing I'd get much from a dual pattern cam.... my dcr would be back up to 8.1:1 though

Last edited by augiedoggy; 07-24-2013 at 06:04 PM.
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Old 07-24-2013, 07:49 PM   #25
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Don't mess with used lifters, toss em. They are like rings on the piston once in that's it if piston comes out rings have to be changed and cylinder honed.
Quote:
Hydraulic Flat Tappet Complete Cam Kit, Chev SB Chev SB Lift: .443/.465 Duration: 288/298 Duration @ .050": 214/224 Lobe Separation: 112 LC Mild idle. Good low end torque. Stock converter OK. In Stock
This cam has a slow ramp. notice the duration from lash (or .006" whatever they use) to the duration at .050". That same 214 @.050" on a lunati is around a 268* at .006". This means that the valve opens much slower than a modern designed cam profile.

Quote:
The crane 100052 at 272 adv 454 lift and 110 lsa 1600-5500seems like a good choice I can get with lifter cheap too (half summits price on eBay).... my iron eagles actually flow better on the exhaust side than intake so I don't really thing I'd get much from a dual pattern cam.... my dcr would be back up to 8.1:1 though
Your playing with fire there. Maybe ok at lower temps but will likely be problamatic.
I'd leave the springs alone. This will allow higher RPMs if you want without having to worry about valve float.
Just remember you usually get what you pay for. It's a real pain to have to go back to fix a "cheap" component later. Not saying more expensive is better but very cheap is probably just that. Good for those budget crate engine builders.
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Old 07-24-2013, 09:23 PM   #26
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Don't mess with used lifters, toss em. They are like rings on the piston once in that's it if piston comes out rings have to be changed and cylinder honed.

This cam has a slow ramp. notice the duration from lash (or .006" whatever they use) to the duration at .050". That same 214 @.050" on a lunati is around a 268* at .006". This means that the valve opens much slower than a modern designed cam profile.


Your playing with fire there. Maybe ok at lower temps but will likely be problamatic.
I'd leave the springs alone. This will allow higher RPMs if you want without having to worry about valve float.
Just remember you usually get what you pay for. It's a real pain to have to go back to fix a "cheap" component later. Not saying more expensive is better but very cheap is probably just that. Good for those budget crate engine builders.
Yes but that slower ramp also brought the dcr way down that's the only reason I was considering it...
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Old 07-24-2013, 10:57 PM   #27
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Originally Posted by augiedoggy View Post
I do currently have the double 1.437 springs that came with my iron eagle heads but I don't know if going to the milder "z28" springs supplied with the elgin kit would be easier on the cam lobes? If I can get away with it I'd just order the summit kit. I do find it funny that summit and lunati have different operating ranges for the same cam.... lunati rates their advertised duration differently so they are usually 6-8 off other manufactuers I read.

The crane 100052 at 272 adv 454 lift and 110 lsa 1600-5500seems like a good choice I can get with lifter cheap too (half summits price on eBay).... my iron eagles actually flow better on the exhaust side than intake so I don't really thing I'd get much from a dual pattern cam.... my dcr would be back up to 8.1:1 though
Check the Crane cams closer. I think the ground in advance is different changing the intake closing point. It gives you a lower DCR than Comp or others with the same advertised duration when I ran the numbers in the past.
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Old 07-24-2013, 11:17 PM   #28
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Check the Crane cams closer. I think the ground in advance is different changing the intake closing point. It gives you a lower DCR than Comp or others with the same advertised duration when I ran the numbers in the past.
I did try to find the advance on them earlier and unless they describe it differently its not even on their site I will keep looking I also found this Howard's cam which has a tight lsa and higher lift but still has the 1500-5600 range , gives me a dcr of 7.5 thoughts?
It looks like the idle would be a bit lopy which I like and won't the 111 LSA and 3 degree advance give me more torque down low while having more top end with the 465 lift? Or am I off base?


Last edited by augiedoggy; 07-25-2013 at 08:07 AM. Reason: incorrect info
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Old 07-25-2013, 10:08 AM   #29
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Default Not Cheap!

Since temps will become an issue,
think about some 1.6 RRs.

Reduced temps and more lift!

Don't forget, more money.

R
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Old 07-25-2013, 10:44 AM   #30
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Since temps will become an issue,
think about some 1.6 RRs.

Reduced temps and more lift!

Don't forget, more money.

R
Won't the higher lift cam do that also? I currently have harland sharp 1.5 rollers on the engine...

I have sent a cam request inti Howard's to see what they recommend... the 279\465 cam seems the have more lope but I don't want that alone to be my deciding factor if its going to take away from the torque at lower and mid range driving range. I'm also assuming I have the 3.08 gears but have not verified since it is a 74 auto...converter is huge and looks original.

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Old 07-25-2013, 11:31 AM   #31
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It looks like the idle would be a bit lopy which I like and won't the 111 LSA and 3 degree advance give me more torque down low while having more top end with the 465 lift? Or am I off base?
Most cams come with 4* advance ground in. I'm not familiar with the advance on the various cams you're referencing but have been assuming 4* advance other than the first one you mentioned that had 6* advance. So if you are talking an additional 3* of advance then it would be at total of 7*.

I believe you are correct in that advancing the cam give you better performance off idle however it then takes some off the top end of the rpm range. It also increases DCR and in your case the potential for detonation.
More valve lift allows better cylinder filling and thereby more cylinder pressure and torque, up to a point. So it does not affect RPM range.
If you want to increase lift on a given cam you can always get 1.6 ratio rockers.

In the reading I have done it shows that as you increase your LSA beyond 108* for a chevy 350 you loose power through out the entire rpm range. So too wide is not good, but neither is too narrow as this causes idle quality to get worse, more overlap and less vacuum. Wider LSA less overlap, better idle more vacuum. These are for a given duration on the cam.
A good compromise for most people is a 110* LSA for a street driven car.
Glad to see 63mako has finally chimed in. His expertise in this area far exceeds mine.
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Old 07-25-2013, 11:36 AM   #32
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Most cams come with 4* advance ground in. I'm not familiar with the advance on the various cams you're referencing but have been assuming 4* advance other than the first one you mentioned that had 6* advance. So if you are talking an additional 3* of advance then it would be at total of 7*.

I believe you are correct in that advancing the cam give you better performance off idle however it then takes some off the top end of the rpm range. It also increases DCR and in your case the potential for detonation.
More valve lift allows better cylinder filling and thereby more cylinder pressure and torque, up to a point. So it does not affect RPM range.
If you want to increase lift on a given cam you can always get 1.6 ratio rockers.

In the reading I have done it shows that as you increase your LSA beyond 108* for a chevy 350 you loose power through out the entire rpm range. So too wide is not good, but neither is too narrow as this causes idle quality to get worse, more overlap and less vacuum. Wider LSA less overlap, better idle more vacuum. These are for a given duration on the cam.
A good compromise for most people is a 110* LSA for a street driven car.
Glad to see 63mako has finally chimed in. His expertise in this area far exceeds mine.
This cam is on a 111lsa with 108 angle....which when subtracted gives me the 3 degree advance ground in... raising that increases my dcr
I do understand that 1.6 rockers will increase lift

Last edited by augiedoggy; 07-25-2013 at 11:44 AM.
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Old 07-25-2013, 12:23 PM   #33
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This cam is on a 111lsa with 108 angle....which when subtracted gives me the 3 degree advance ground in... raising that increases my dcr
Yes the difference between the ICL and the LSA is the ground in the ground in advance.

This is a good article on cam stuff that I found if it helps.

http://www.carcraft.com/techarticles...c/viewall.html
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Old 07-28-2013, 02:35 PM   #34
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I ended up going with the voodoo 262 can after seeing a post from UDHarold on another forum confirming it has a ICA of 61 degrees.... also taped off my heads and filled them with a syringe to check chamber volume more efficiently than before and found the chambers are actually about 65.5 cc... so my DCR is under 8.1 which with the heart shaped combustion chambers has been reported to work with 91 octane... I have 93 here so I should be good.. if not I will retard the cam.
Desktop dyno results had the best performance with this can by far.
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Old 07-28-2013, 08:31 PM   #35
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Sound good if your Chambers are at 65.5 cc's and the pistons are at 7cc's this should work with the voodoo 262 if it in fact does have a ICA of 61*. Have you verified that with Lunati?
Even if the ICA were 59* you end up with 7.94 DCR wich could be reduce by retarding the cam 2* for a 61* ICA giving you a DCR of 7.83. Nice RPM range on that cam.
Retarding the cam 2* would not be noticable difference in performance but may make all the difference in detonation.
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Old 07-28-2013, 11:28 PM   #36
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This might be helpful.
http://forums.corvetteforum.com/c3-t...lculation.html
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Old 07-29-2013, 08:06 AM   #37
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Yes the 61 degrees came from UDHarold himself on another forum... he designed the voodoo series as well as the XE series.... they are the closest performing camshafts to the rollers. According to the info I put in desktop dyno this cam outperformed all others by a long shot at 6000 rpm or less...I know the numbers are a bit high but I got over 400hp and well over 400 lbs of torque (with a 750 Carb and open exhaust in the simulation.).. I really tried to justify buying a roller but just recently learned I'm buying the family homestead so gotta keep it conservative and things keep popping up..

http://www.chevelles.com/forums/arch...p/t-23037.html

Mako I know it doesn't check with the formula you provided but as I understand it, its because of the way the duration is ground vs the way they advertise it...
Btw thanks again for your help guys.

Last edited by augiedoggy; 07-29-2013 at 08:20 AM.
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Old 07-29-2013, 08:58 AM   #38
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I just hate it when I make a mistake......
I forgot the 256 and 262 were on 112. Those numbers are for 110 LSA.....
The correct numbers for 112 LSA are:
VooDoo 256--
IVO 18BTDC IVC 58 ABDC EVO 65 BBDC EVC 17 ATDC
VooDoo 262--
IVO 21BTDC IVC 61 ABDC EVO 68 BBDC EVC 20 ATDC

Sorry for all the un-needed calculations. The extra 3 intake closing should still be added.
It looks like according to UDharold that the IVC is really at 64* If I understand his comment about adding 3* to the IVC point.

I read some of his posts on the chevelle forum and my understanding is due to the asymmetrical lobe design, one cannot assume a constant slope from .050* to the IVC angle and this is why using the normal calculators, or calculating IVC from .050*, which assumes a symmetrical lobe design will come back with a higher than actual DCR and earlier IVC angle.
What I don't know is if the calculators use lash or SAE standard of .004* for the IVC point. Maybe someone else knows the answer to this. Interesting that when I select the Lunati 262 from the Jeep strokers DCR calculator it puts the IVC at 59*, not even close to what UDharold is saying it is.
Nice job on your homework augidoggy. This information will certainly help others when deciding on a cam to use.
Are you gonna dial in this cam? If so maybe you can check the IVC at lash and at .004* and let us know what they are. I'd be interested in those results.
On my Lunati cam I found that the valve events were not where the cam card said they should be. When I talked to Lunati about it the sales rep told me that the computer program for the card assumes a symmetrical design but the cam lobes are asymmetrical. So you really don't know what you have for sure until you dial it in.

Last edited by REELAV8R; 07-29-2013 at 09:32 AM.
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Old 07-29-2013, 11:27 AM   #39
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I'm not really sure how to dial the cam in. I assumed the listed cams in the jeep calculator were for jeeps and did not pertain to SBC grinds?
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Old 07-29-2013, 01:07 PM   #40
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I assumed the listed cams in the jeep calculator were for jeeps and did not pertain to SBC grinds?
Good point, your right in that the listed grinds on the Jeep strokers DCR calc are referring to a cam for the Jeep. If you compare the grinds they are nearly identical. The only difference is 1* @050* on the duration for the voodoo 262 on the two different engines. So IVC may be 1* Different as well can't say for sure. It's possible there are other differences in the asymmentry of the lobes without us knowing.
I compared the xe262 with the Jeep strokers 262 cam and the IVC closing angle is 1* different as is the ICL. So yes there are small differences.
I punched in your numbers into this calculator
http://www.projectpontiac.com/ppsite...tio-calculator
and it came up with nearly identical numbers. So I think the IVC is being calculated in the same place with either calculator. The only difference was .01 on the DCR which could just be how it was rounded.
In either case the IVC it appears is being calculated based on a symetrical lobe. It sounds like UDharold makes a good point in attempting to calculate asymmetrical cam grind closing points based on .050* openings.
When dialing in my cam I found that the IVC was 1* later than the cam card called for @.050. I unfortunately did not check it at .004* or lash.
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