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Re-camming a 472 Crate Hemi #2032372 03/16/16 12:59 PM 03/16/16 12:59 PM
Joined: Feb 2006 Posts: 1,057 The Great White North RAMM OP super stock
RAMM OP super stock Joined: Feb 2006 Posts: 1,057 The Great White North	I could use some friendly advice on this one. Out of my element a little bit here. A customer has purchased a 472 Crate Hemi and brought it to me for verification, customization and a little more power. Upon arrival I had the opportunity to dyno test the engine and it made a little over its rated power (535 hp 550 tq IIRC) and ran well for what it is. Customer wants 600hp- I suggested a single plane intake with a 1050 Dominator, some head work and that's about it. So after discussing his realistic intentions and tearing it down, the game plan has evolved into basically the intake/carb change, re-ring/re-hone (cylinders were washed a a bit)and a cam change. The customer intends to use this in a very very nice 'Cuda w/6spd manual with power brakes and A/C on pump premium of course. The Engle K8 hydraulic cam had a rough idle and poor manifold vacuum and I blame the hydraulic lifters for the power nosing over at about 5300-5500 rpm. (I thought Hemi's were supposed to rev?) I feel a solid flat tappet is the best choice for stable valvetrain function here. Not going solid roller. Any ideas or real world feedback on some of the more tame Hemi cam choices? I plan to order a full custom cam w/nitriding and EDM lifters so custom specs are welcome. The pic is how it was tested in Sep 2015. Thanks, J.Rob 2009 PHR\EMC Competitor 2010 PHR\EMC Competitor 2011 PHR\EMC Competitor 2012 PHR\EMC Competitor 2013 PHR\EMC Competitor 2014 HotRod/EMC Competitor 2015 HotRod/EMC NoShow 2016 HotRod/EMC 3rd place SPEC Bigblock 2018 HotRod/EMC 7th place G3

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032450 03/16/16 02:57 PM 03/16/16 02:57 PM
Joined: Aug 2003 Posts: 44,041 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 44,041 Bend,OR USA	Before tearing it down I would check and set the valve lash on that cam first and redyno it. I raced a 1970 hemi Cuda with a cheater Racer Brown hydraulic cam and lifters with the preload set at 1/4 turn on the adjusters from zero I had treid one full turn, 1/2 turn, zero preload and one or two other settings at the races over several months and the 1/4 turn hot worked the best, I shifted that motor at 7000 RPM That was when NHRA required us to use the stock valve springs and cam specs. Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032461 03/16/16 03:18 PM 03/16/16 03:18 PM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	I agree with Cab,check the setting before changing anything.Play with fuel and timing and you should see some HP gain.A manifold and carb change would be your best bet for HP gain also.If you insist on a cam change stay with a hydraulic cam with 530/550 lift. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Re-camming a 472 Crate Hemi [Re: B G Racing] #2032463 03/16/16 03:21 PM 03/16/16 03:21 PM
Joined: Feb 2006 Posts: 1,057 The Great White North RAMM OP super stock
RAMM OP super stock Joined: Feb 2006 Posts: 1,057 The Great White North	Why stay with a hydraulic cam? I did adjust the preload while it was on the dyno and did manage to find some power. The real issue is this cam will have very little vacuum for P/B and A/C. J.Rob 2009 PHR\EMC Competitor 2010 PHR\EMC Competitor 2011 PHR\EMC Competitor 2012 PHR\EMC Competitor 2013 PHR\EMC Competitor 2014 HotRod/EMC Competitor 2015 HotRod/EMC NoShow 2016 HotRod/EMC 3rd place SPEC Bigblock 2018 HotRod/EMC 7th place G3

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032471 03/16/16 03:32 PM 03/16/16 03:32 PM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	What are the specs on the cam?We usually find we have sufficient vacume with proper tuneing and timing.If you want to be playing with valve adjustment(pulling those covers of in a car that has tight clearance) and the oil mess then go to a solid flat or roller and enjoy all the valve train noise and the maintaince. If vacume is minimal you can add a tank and even a electric vacume pump.We have hemis with 600+ lift roller cams that produce 15+hg of vacume if tuned correctly. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032597 03/16/16 06:27 PM 03/16/16 06:27 PM
Joined: Jan 2011 Posts: 4,785 Utah and Alaska astjp2 master
astjp2 master Joined: Jan 2011 Posts: 4,785 Utah and Alaska	my hemi has 112 lsa, .620/.628 lift 248@.050 and I get almost 17 inhg. Crane mechanical roller spec'd by Chase Knight... Tim 1941 Taylorcraft 1968 Charger 1994 Wrangler 1998 Wrangler 2008 Kia Rio 2017 Jetta I didn't do 4 years and 9 months of Graduate School to be called Mister!

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032681 03/16/16 08:40 PM 03/16/16 08:40 PM
Joined: Jan 2003 Posts: 31,303 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 31,303 Oregon	I'd think a solid flat tappet in the range of a Mopar .528 or the Comp 294S would carry a 472 Hemi into the 600 hp range. I know they'll make that kind of power with a 470 inch wedge and the Hemi heads are much better. I don't think you need a Dominator carb to crack 600 hp. It will help on the dyno but not so sure about street driving. Maybe if you go with the new Gen 3 950 Dominator. I'm pretty sure a 850DP will crack 600 hp without any trouble. Not sure about the single plane vs. dual plane. I'd probably stick with the dual plane for a street car but it could go either way. Depending on who built that crate Hemi the low power output could be due to assembly errors. The last crate Hemi I was involved with was a total mess inside. Looked like it had been built by a drunk monkey.

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032738 03/16/16 10:14 PM 03/16/16 10:14 PM
Joined: Jan 2003 Posts: 13,266 Benton, IL. D DaveRS23 Master of nothing...
DaveRS23 Master of nothing... D Joined: Jan 2003 Posts: 13,266 Benton, IL.	At the recent Indy event, I spoke with Ken Lazzeri of ICH for awhile about my current Hemi project and asked for his recommendations on intake manifold and headers. His answers surprised me a little. It would be nice if there were more info on each of Indy's many intakes, but if it is out there, I certainly haven't found it. Anyway, for my 540" 250* cam street Hemi, he strongly recommended the dual plane intake. He said it was good till about 6,500 RPM and that the street Hemis needed all the help they could get with torque. For a mild 540" Hemi, the last thing I thought it would need was a dual plane. But he had a table full of all of his Hemi intakes, so I don't see a reason for him to misrepresent the situation. As to hedders, I had planned to use the 2 1/8" TTIs just to make the install a little easier. And I figured the smaller tubes wouldn't hurt the street engine's performance much if any at all. Wrong again. Ken said that any 540 Hemi would really want 2 1/2", so 2 1/8" would be a real cork. 2 1/4"s would be the bare minimum. And that any exhaust restrictions would cost real performance on these things. Fortunately, I have electric cut-outs, so I'm good there. Indy had a wall full of TTI headers and the Hemi headers were all the same price and he had them all. So I don't see any incentive for him to say anything but the truth on this subject either. I would be interested in anyone else's opinion on his comments. My experience is with wedges and Ken's advice flies in the face of my experience with similar sized wedges. But I bought the items that he suggested. Not from Indy because of the sales tax. But I bought what he recommended. Master, again and still

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032777 03/16/16 11:03 PM 03/16/16 11:03 PM
Joined: Jun 2006 Posts: 5,192 CT GTX MATT master
GTX MATT master Joined: Jun 2006 Posts: 5,192 CT	I have a buddy that has a 9.5:1 528, stock MP heads, cam is a solid flat tappet around 256 @ .050 and .560ish lift, Barton single plane intake, 4150 DP (I think a 950), 2 1/4 headers, made around 640 HP and 650 ft lbs, over 600 ft lbs from 3k and up, very flat torque curve. He originally dynoed it with the stock crate engine dual plan and it was down something like 60-70 HP. Now I need to pin those needles, got to feel that heat Hear my motor screamin while I'm tearin up the street

Re: Re-camming a 472 Crate Hemi [Re: DaveRS23] #2032788 03/16/16 11:08 PM 03/16/16 11:08 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Originally Posted By DaveRS23 At the recent Indy event, I spoke with Ken Lazzeri of ICH for awhile about my current Hemi project and asked for his recommendations on intake manifold and headers. His answers surprised me a little. It would be nice if there were more info on each of Indy's many intakes, but if it is out there, I certainly haven't found it. Anyway, for my 540" 250* cam street Hemi, he strongly recommended the dual plane intake. He said it was good till about 6,500 RPM and that the street Hemis needed all the help they could get with torque. For a mild 540" Hemi, the last thing I thought it would need was a dual plane. But he had a table full of all of his Hemi intakes, so I don't see a reason for him to misrepresent the situation. As to hedders, I had planned to use the 2 1/8" TTIs just to make the install a little easier. And I figured the smaller tubes wouldn't hurt the street engine's performance much if any at all. Wrong again. Ken said that any 540 Hemi would really want 2 1/2", so 2 1/8" would be a real cork. 2 1/4"s would be the bare minimum. And that any exhaust restrictions would cost real performance on these things. Fortunately, I have electric cut-outs, so I'm good there. Indy had a wall full of TTI headers and the Hemi headers were all the same price and he had them all. So I don't see any incentive for him to say anything but the truth on this subject either. I would be interested in anyone else's opinion on his comments. My experience is with wedges and Ken's advice flies in the face of my experience with similar sized wedges. But I bought the items that he suggested. Not from Indy because of the sales tax. But I bought what he recommended. What would be your max rpm... to me.. 2 1/2 sounds big and when he said you could use all the torque you can get.. again they sound big and the collector length on the TTi headers is real short which hurts the torque.. is that a 4" collector... but I dont know all the engine specs to really say what it needs

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2032985 03/17/16 10:05 AM 03/17/16 10:05 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	We find a dual plane manifold falls off well before 6000 rpm(depending on the combo) in most applications.We had a hydraulic cam 471" hemi with the dual plane manifold that ran consistant 11.70s,changed the manifold to a single plane,upped 2 jet sizes,added 2* timing and nothing else,it ran consistant 11.40s. As far a headers we found in many cases when you exceed 2.250 you will see a power drop.Most all our hemis run 2 1/8 and 2 1/4.My opinion base on over 50 years of building and racing hemis,street and strip that a 540" engine with a 250 duration hydraulic cam can have effective torque when installed at 106*.we have used this cam quite effectively in a race application and would recommend staying with a 240 duration for street friendly use. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2033057 03/17/16 11:34 AM 03/17/16 11:34 AM
Joined: Jan 2003 Posts: 14,554 So. Burlington, Vt. F fast68plymouth I Live Here
fast68plymouth I Live Here F Joined: Jan 2003 Posts: 14,554 So. Burlington, Vt.	Personally, I would explore something like the edelbrock victor manifold for that application, or the stage v dual carb. My preference would be to avoid a 4500 series carb for a 470-ish cu motor that's likely going to be chugging along in overdrive with the a/c running. I would spend a little time on the heads. A basic clean-up will get them easily into the 370cfm range. Flat tappet cam with ramps as fast as you feel comfortable with for a real street car. Something like a 248/254-112. I would also verify the net rocker ratio of what you have there before you make the final decision about lobe families. 68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads

Re: Re-camming a 472 Crate Hemi [Re: fast68plymouth] #2033627 03/18/16 08:31 AM 03/18/16 08:31 AM
Joined: Feb 2006 Posts: 1,057 The Great White North RAMM OP super stock
RAMM OP super stock Joined: Feb 2006 Posts: 1,057 The Great White North	Originally Posted By fast68plymouth Personally, I would explore something like the edelbrock victor manifold for that application, or the stage v dual carb. My preference would be to avoid a 4500 series carb for a 470-ish cu motor that's likely going to be chugging along in overdrive with the a/c running. I would spend a little time on the heads. A basic clean-up will get them easily into the 370cfm range. Flat tappet cam with ramps as fast as you feel comfortable with for a real street car. Something like a 248/254-112. I would also verify the net rocker ratio of what you have there before you make the final decision about lobe families. The customer is adamant about keeping it single carb. I was considering the 950 4500 Gen3 to avoid the "chugging". I will be spending some time on the heads for sure. Thankyou for the advice guys. J.Rob 2009 PHR\EMC Competitor 2010 PHR\EMC Competitor 2011 PHR\EMC Competitor 2012 PHR\EMC Competitor 2013 PHR\EMC Competitor 2014 HotRod/EMC Competitor 2015 HotRod/EMC NoShow 2016 HotRod/EMC 3rd place SPEC Bigblock 2018 HotRod/EMC 7th place G3

Re: Re-camming a 472 Crate Hemi [Re: RAMM] #2033832 03/18/16 02:13 PM 03/18/16 02:13 PM
Joined: Jan 2011 Posts: 4,785 Utah and Alaska astjp2 master
astjp2 master Joined: Jan 2011 Posts: 4,785 Utah and Alaska	Getting consistent and good rocker ratio's will lend itself to getting a proper cam selected. My factory wide pads were 1.32~1.4 ratio so I actually spend the money for stageV rollers and dechilles shafts, I think that it gave a much more representation of the Crane roller spec's that I installed. Loosing that much ratio would have made my engine short on expected power. Tim I wonder why so many people are afraid of roller cams? With the lack of good zinc ratio oils and the number of flat tappet cam failures, I am surprised that more don't go for the roller deal... 1941 Taylorcraft 1968 Charger 1994 Wrangler 1998 Wrangler 2008 Kia Rio 2017 Jetta I didn't do 4 years and 9 months of Graduate School to be called Mister!

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