update on Cam choice.
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Melting Slicks
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From: Chetwynd B.C.
update on Cam choice.
Thank you all for your help 
I finally made a decision on my cam choice. With advice from all of you, the Comp Cams tech and my engine builder, I have decided on a hydraulic roller custom grind of adv. dur. 270/276 dur.@.050 218/224 lift .605/.600 lsa 113. We are confident that this will give me the bottom end torque along with the highway driveability I am looking for. 
Will also have the billet core and the bronze tip fuel pump pushrod.
Thanx again for everyones help in getting me to the point where I could see thru the mud and understand (although only a little) what I was looking at.
shmoky
I finally made a decision on my cam choice. With advice from all of you, the Comp Cams tech and my engine builder, I have decided on a hydraulic roller custom grind of adv. dur. 270/276 dur.@.050 218/224 lift .605/.600 lsa 113. We are confident that this will give me the bottom end torque along with the highway driveability I am looking for.
Will also have the billet core and the bronze tip fuel pump pushrod. Thanx again for everyones help in getting me to the point where I could see thru the mud and understand (although only a little) what I was looking at.
shmoky
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From: Lompoc, CA. Santa Barbara County
I plan on converting to hydraulic rollers using the Chevy LT4 Hot Cam. Here are the specs:
218/ 228, Lift at Valve .492/ .492, with my 1.65 ratio roller rockers the lift will be .541. I hope that is not too mild for my motor with a performer rpm air gap and holley commander 950 tbi, and 2 1/2 headers. Torque and driveability is what I want too, and of course 12 second quarter mile times.
Edit: I just looked up your other thread and you have a big block.......nevermind.
218/ 228, Lift at Valve .492/ .492, with my 1.65 ratio roller rockers the lift will be .541. I hope that is not too mild for my motor with a performer rpm air gap and holley commander 950 tbi, and 2 1/2 headers. Torque and driveability is what I want too, and of course 12 second quarter mile times.
Edit: I just looked up your other thread and you have a big block.......nevermind.
Last edited by Bee Jay; Dec 5, 2007 at 05:26 PM.
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I suggested, on that post whatever the choice make sure the DCR is below 8 with iron heads. This cam, with 218 intake duration @ .050, I don't think will get him there. My 10.4 aluminum head motor needed 238 intake duration @ .050 to get to 8.25 DCR. Just my opinion, but as you know, there are those out there that don't think DCR is relevant.
Last edited by 63mako; Dec 6, 2007 at 01:26 AM.
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From: FL.
Hope I dont open another can of worms with this Question, But Whats your Quench number Look Like? Thats a factor as you start getting Marginal with higher dcr numbers.
I use a Comp Hyd. Roller 218/224@.050 ,
.528 /.536 Lift w/1.6 rockers 10/1 sc. 200cc "Aluminum Heads"
.040 Quench.
It Has 8.25 dcr according to calcs done by members on the forum.
I started having some reservations about the intake duration being to short, But already had the Cam installed and engine almost finished.
It uses Total timing 36* @3000rpm and tuned up easily ,by the Book. Has Nice idle , runs Real strong through the gears and suprisingly good Gas Mileage. No Pinging.
Next Cam change, Ill increase the int. duration to 224@.050 Im certain that will lower the dcr a half point to 7.5 or so. The engine would like it better without power compromise, I think so anyway.
I use a Comp Hyd. Roller 218/224@.050 ,
.528 /.536 Lift w/1.6 rockers 10/1 sc. 200cc "Aluminum Heads"
.040 Quench.
It Has 8.25 dcr according to calcs done by members on the forum.
I started having some reservations about the intake duration being to short, But already had the Cam installed and engine almost finished.
It uses Total timing 36* @3000rpm and tuned up easily ,by the Book. Has Nice idle , runs Real strong through the gears and suprisingly good Gas Mileage. No Pinging.
Next Cam change, Ill increase the int. duration to 224@.050 Im certain that will lower the dcr a half point to 7.5 or so. The engine would like it better without power compromise, I think so anyway.
Last edited by 69vettester; Dec 6, 2007 at 08:34 AM.
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Well, that looks like an awful responsive little cam. That's a lot of lift with duration that short.
Not sure what all your intentions are with it..but I can tell you it won't be a big HP maker at all. That short of duration and a wide LSA will make it smooth and it will drive nice. It's going to resemble what folks do with EFI LT-1's.
Don't expect to spank any new LS motors that pull up beside you!
And I agree...without fuel/timing management that's going to be definitely on the edge of detonation all the time unless you live at 5000 ft. Better be a good tuner.
Jim
Not sure what all your intentions are with it..but I can tell you it won't be a big HP maker at all. That short of duration and a wide LSA will make it smooth and it will drive nice. It's going to resemble what folks do with EFI LT-1's.
Don't expect to spank any new LS motors that pull up beside you!
And I agree...without fuel/timing management that's going to be definitely on the edge of detonation all the time unless you live at 5000 ft. Better be a good tuner.
Jim
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i meant to ask,
how is the mpg on a BB 454 with 230 ?
Thanks, i don't have much info on BB mpg.
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St. Jude Donor '08-'09
As a rule the more cubic inches the more duration needed. A 454 needs a little more cam than a 427 to operate the same. Higher compression needs more duration. A hot cam in a 10.5 to 1 350 will be much more docile in a 10.5 to 1 406.
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Any body recommending a sub 230 h-roller cam does not know anything about big ci motors and the fact that a roller cam will run smoother and have higher vacuum than an equivolent flat cam of the same duration.
Gas mileage is a function of engine efficientcy. Hot rodded motors get better mileage than low hp low compression motors. I have no problem getting over 18 mpg and still have a 600 hp 427 ci motor
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From: central FL, near the beach.
george
u don't have a BB!
.
the OP talked to comp and this is what he wants!
.
i agree about a cheaper cam.
i'd put in a solid flat tappet ~242/248/114lsa
but, HEY, i'm not the owner of this car!
The guy is 50 and just wants to cruise around. What is wrong with that? Bet it still makes 440-450hp. and gets good mpg for a REAL BB.
u don't have a BB!
.
the OP talked to comp and this is what he wants!
.
i agree about a cheaper cam.
i'd put in a solid flat tappet ~242/248/114lsa
but, HEY, i'm not the owner of this car!
The guy is 50 and just wants to cruise around. What is wrong with that? Bet it still makes 440-450hp. and gets good mpg for a REAL BB.
Last edited by Matt Gruber; Dec 8, 2007 at 01:16 PM.
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From: Millington Illinois
St. Jude Donor '08-'09
george
u don't have a BB!
.
the OP talked to comp and this is what he wants!
.
i agree about a cheaper cam.
i'd put in a solid flat tappet ~242/248/114lsa
but, HEY, i'm not the owner of this car!
The guy is 50 and just wants to cruise around. What is wrong with that? Bet it still makes 440-450hp. and gets good mpg for a REAL BB.
u don't have a BB!
.
the OP talked to comp and this is what he wants!
.
i agree about a cheaper cam.
i'd put in a solid flat tappet ~242/248/114lsa
but, HEY, i'm not the owner of this car!
The guy is 50 and just wants to cruise around. What is wrong with that? Bet it still makes 440-450hp. and gets good mpg for a REAL BB.
http://www.holley.com/50268.asp
Last edited by 63mako; Dec 8, 2007 at 01:46 PM.
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63mako
that is discouraging! compression is very important.
.
I was told 10 yrs ago that w/xe250 i was using 206/212/110 in my 355 would ping if i went over 9:1, so i thought i was being bold
with 9.2:1 and .065 quench and hot underhood air.
1 tank of 91 and i knew i was hosed. back to 87
i really wanted to run hi-test. So i don't see why a 10.3 is high w/ 91. I figure i'd need ~10:1-10.5 to take advantage of premium fuel. why not a BB? are they prone to pinging more than SB? coud be. big piston, poor flame travel?
that is discouraging! compression is very important.
.
I was told 10 yrs ago that w/xe250 i was using 206/212/110 in my 355 would ping if i went over 9:1, so i thought i was being bold
with 9.2:1 and .065 quench and hot underhood air. 1 tank of 91 and i knew i was hosed. back to 87
i really wanted to run hi-test. So i don't see why a 10.3 is high w/ 91. I figure i'd need ~10:1-10.5 to take advantage of premium fuel. why not a BB? are they prone to pinging more than SB? coud be. big piston, poor flame travel?
Last edited by Matt Gruber; Dec 8, 2007 at 01:56 PM.
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Ecuse me for stepping in but I wish to get some related info..I have a 454 with iron heads,10 to 1 cr,3:08 gear n comps xe268 cam..I will be switching to 3:70 gear so my question is would you recomend upgrading my cam...Thanx...Jerrylee///
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St. Jude Donor '08-'09
63mako
that is discouraging! compression is very important.
.
I was told 10 yrs ago that w/xe250 i was using 206/212/110 in my 355 would ping if i went over 9:1, so i thought i was being bold with 9.2:1 and .065 quench and hot underhood air.
1 tank of 91 and i knew i was hosed. back to 87 i really wanted to run hi-test. So i don't see why a 10.3 is high w/ 91. I figure i'd need ~10:1-10.5 to take advantage of premium fuel. why not a BB? are they prone to pinging more than SB? coud be. big piston, poor flame travel?
that is discouraging! compression is very important.
.
I was told 10 yrs ago that w/xe250 i was using 206/212/110 in my 355 would ping if i went over 9:1, so i thought i was being bold
with 9.2:1 and .065 quench and hot underhood air. 1 tank of 91 and i knew i was hosed. back to 87
i really wanted to run hi-test. So i don't see why a 10.3 is high w/ 91. I figure i'd need ~10:1-10.5 to take advantage of premium fuel. why not a BB? are they prone to pinging more than SB? coud be. big piston, poor flame travel?
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From: central FL, near the beach.
Matt, the answer is cubic inches. A 355 will require less cam duration than a 406 with the same static compression to run in a similar rpm range. Smaller chamber and less stroke = less A/F mix drawn into the cylinder. That is why with bigger stroke and bore you need more duration. shmoky's cam duration choice may very well work fine on a 350 with similar compression just don't think it is a good choice for a 454 considering all factors.
454
ZZ454/ 440hp
211/230 weenie cam! see! 9.6:1 5500rpm
this is not far off the OP's goals.
GM knows nothing about "this classic muscle car motor" ?
OK. mako, u say it will ping. Maybe not? is that possible in cold canada it won't ping? ANY chance?
The thing i question is the 370 rear. he should have a 336 imo. but then again i don't drive in canada, maybe he cruises at 55-70?