dr_hunt
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Posts posted by dr_hunt
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Yeah, a 4 inch spacer looks like what you need.
How did you come up with that track width in the rear? -
Yup, that's what I mean, pushes the piston farther up, who knows what I was thinking at the moment, but is was backwards wasn't it. But that doesn't mean it has more compression, it depends on the valve relief cut volume, could still have the same compression even though it has a different compression height. I've run hypers before, they tout the tighter bore clearance attributes to better ring seal which makes sense. Better than regular cast aluminum pistons. Since your running aluminum heads then you can easily run 10:1 on pump gas IMO. Compression is not much of a factor as compared to cam selection as a whole when matched to the entire engine combination.
You'll find that even with low compression, tight LSA's matched with small duration cams like about 210 to 215 at .050 yield great TQ in the low to midrange and make pretty good daily driving motors.
I tend to opt for stall converters to eliminate the lazy bottom end TQ plus it gives you a better TQ multiplier in the converter.
Bet your z will scoot with whatever you choose. Damn sleeper cars.
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I posted a thread about it, probably do a search on the sanderson block huggers with 1-7/8" primary tubes for bigger ci and hp engines. Ceramic coated were $400+ delivered but work with the angle plug heads. Honestly the plugs are super easy to get to with those headers.
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1.561 is factory stock for a 350 with the 5.7 inch rod. The 1.565 will mean the piston is down in the hole .004 more at TDC which effects compression ratio.
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Well, that's a good question. I have 3 sets of AFR's laying around and on various enignes, 2 sets of 220's and 1 set of 227's, all work flawlessly and make great power. But all are roller cam application heads and fully cnc'd versions that I invested around $1700 to $2200 per pair over the years.
But in undertaking my jeep build, trying to do it on the cheap I was perplexed as to what heads to put on it. I've got $800 in the shortblock with the stock vette pan on it. I had a set of world products sportsman heads 200cc but they needed hardware like valves, springs, retainers, locks, guideplates, studs, and a valve job. By the time I get all that I'll have $500 in them and I wanted this jeep to be a force in the neighborhood and pieces just kept becoming available like a th350 with a 205 t-case, 3500 stall (nitrous and t brake) converter for $100, etc, etc. So it became obvious that just any old set of heads wouldn't do and a bigger bumpstick was probably in order to take advantage of the converter. My first cam choice fell through and I scored a bigger cam anyway for less $$$. Soooooo, while shopping on ebay for steal of a deal items I stumbled across those. Actually I had bought jeg's heads only to find that they didn't even have them, so I got these instead.
I'm about ready to fire mine for the first time tomorrow and the custom drivelines will be done by U-joints inc. of Albuquerque on Wednesday afternoon, so I'll drive it down to the local muffler shop and have some duals with stock, (cough cough), I know, I'm sick, mufflers put on it. Yup, you heard it right, even though I have single chamber flowmaster race mufflers on the shelf I'm going stock, super quiet, kick your butt, sleeper jeep that'll probably run in the 12's in the quarter mile. Yup, got a B&M z gate shifter to bang the gears with while screaming up the hills. Sad, had to use my ceramic coated sanderson headers on the jeep cause nothing else would fit. So, will have to order me some more sanderson block huggers for my z project. Ah, don't cry, it's only an addiction to speed.
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I think so Wayne, we will see though how they work. I hope to have this engine running by the end of the weekend or even by mid next week. I hope it makes somewhere close to 425hp. My rockers are adjustable ratio so I'll play with that some, but to start I'll run 1.6 in the intake and 1.5 on the exhaust which should yield about .540 lift on the intake and .525 on the exhaust, which should compliment the heads reported flow numbers nicely. I'm putting a victor jr. on it also as I scored a 3500 stall converter for $100 so it won't be seeing much of the low rpm band.
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Nice! Did you get a shipping number or anything for them? I haven't heard on mine except asking about spring rates. I might email them tomorrow.
Yeah, it takes them 5 to 7 days to build the heads, then they sent me a tracking number and poof they were here.
I took one cylinder set of valves apart. Very nice. All the work is done on a serdi machine, total quality from what I see. The heads look alot like the AFR's in some respects and alot like a set of World Products heads in some respects. My guess is that like most production parts from aftermarket, somebody sent them over to china and these are basically clones. While not CNC machined ports like my AFR's they are very nice and the casting quality is very, very good. Just look at these pictures, the inside of the ports and the water jacket is completely smooth, no casting flash and hasn't been ground off, just quality castings. Deck thickness is close to the same as my afr's, they are beefy, weigh 58 lbs for the pair. 2.05 intake valves, 1.6 exhaust valves. Very decent for the price and a good value IMO after seeing them first hand. I'll run them and follow up.
As for flowing them grumpy, I could, but I'm not going to spend the money to do that. I will run them however and see what I think. But you can see for yourself, they are very nice for the price as compared to re-working a set of stock, even vortec heads which will set you back $500 by the time you get screw in studs, guideplates, springs, valves, 10 degree retainers, 10 degree locks, bronze guides, etc, etc. And I doubt you can fit 2.05 valves in vortec or any gm head anyway with stock valve spacing.
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I have the trans-dapt dual filter unit on the boys z. Look for a pressure drop from your original oil pressure reading. It makes changing oil alot easier but what I was looking for is that alcohol puts water, methanol in the crank case and the dual filter elements let me be more comfortable than I was with just one filter and changine it every race.
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I bought these the other day. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=150310087856&viewitem=&sspagename=STRK%3AMEWNX%3AIT About all I can say is what a great looking smoking deal these were!
They look awesome. I have a pair of AFR 220's laying on the bench, fresh and ready to go so I compared them. Guys, if your in the market for a set of aluminum heads to compliment your engine, seriously take a look at these heads. I talked to the guy on the phone and encouraged him to register here as a vendor.
I ordered these and they were delivered as stated in the auction and boy do they look good. 2.05 and 1.6 valves, pretty good flow numbers and they even take vortec intake manifolds. No heat riser, no name, no brand, but they are pretty darn good quality and you can't beat the price!
I'll run them and let you all know what I think of them installed on a little 355 chevy in my jeep!
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What a frustrating couple of weeks. I ordered these heads from Jeg's, through ebay, using buy it now and paid for them. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=350254258994&viewitem=&sspagename=STRK%3AMEWNX%3AIT
Jeg's calls me 2 days later to tell me that they are discontinued and not for sale anymore. Ok, so what else you got? They transfer me to a salesman who tells me that "someone beat me to the heads and that they were already sold." Ha, really, check the aution, says 2 available!, so he does, but can't explain that. He transfers me to his supervisor who says that it was for one head, not two but they will sell me a set of patriot heads for $899 each or $1700 total! Wowsa, what a royal screwing I say!! I can buy AFR for less, to which he says "buy them then"!!! OK, so I want my money back, sorry he says, leaving for vacation and won't be back for a week, call back later! Yowsa!
So, I had also bought a lunati cam kit, also from Jeg's, paid through paypal, $288.38 and never received item. Called Jeg's, they say they got the money but have no record of me ordering item as the order was cancelled 2 days later. OK, so I am like how can you cancel an order that didn't exist you moron! To which the reply is, call back on Monday to get a supervisor! What a bunch of tools!!!!
So, I contacted paypal and got the head money back, but not the cam money yet. Bought another cam, from someone else this time. It is this one LUNATI SBC 276/284 VOODOO CAM & LIFTER KIT #60104LK.
Have to tell you that IMO Jeg's sucks in about every way imaginable!
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IMO the holley pumps are pretty much junk. I went through countless holley black pumps before buying an aeromotive to which I have to say, you get what you pay for. IMO a mechanical pump is ideal as the pump output increases with engine rpm whereas an electric pump flows pretty much the same all the time unless you have voltage drop somewhere along the time it's running which happens when guys don't run alternators for racing.
IMO a good quality mechanical race pump will feed your needs and a belt driven pump will carry you until you break the 2000hp mark.
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rate is actually lb/in (lbs per inch). Torque is lb-in (lbs times inches) or lb-ft. I know doc knows this - just correcting it for those that might be reading this and learning. Us anal-retentive engineers can't let that little stuff just slide by - sorry!
:lmao: Wouldn't expect anything less!!!Very true. Heat build up, flexing of the parts that isn't necessary (and takes away from true lift), increased where at the sliding points (cam/flat tappet interface, etc.), accelerated lowering of the actual spring rate (and therefore seat and open force). You have to balance not having so much spring force/rate that you don't cause these things needlessly, versus losing power due to noticable valve float (engine won't rev past it), and probably also losing power hundreds of rpm below that point too. Some interesting reading here: http://www.briggsracing.com/technical_talk/principals_of_valve_springs.pdfYup, Pretty cool stuff. Oddly enough in this day and age, titanium retainers are still a good idea IMO and I'd run the same in valves if I won the lottery.
If a person was to do some digging on the internet related to pushrod deflection caused by running too much spring pressure you would be amazed at what you might find. Another interesting point is rocker arm stud deflection. I run 7/16" studs on anything over .500 lift. If you delve into this area of deflection, you will find a host of problems that a little attention to parts selection can mean the difference between a winner and a looser.
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How do you figure spring rates for a cam?
http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=187&sb=2
That's the cam I linked to above. It lists part numbers for two sets of springs, one 322 in/lb and one 344 in/lb, I'm sure both work but I'm curios how you go about finding what is needed. In Vizard's "Small blocks on a Budget" book he says 220-240 lbs is adequate for a street motor and 350 lbs is the maximum. Am I confusing measurements?
Cam manufacturers have the spintron and have spent thousands of hours determining the correct spring and installed spring height and what works and doesn't work with their grind of cam. It is really kind of pointless to try to out engineer, out guess, and out theorize the cam manufacturer as to what spring rate, seat pressure and open pressure you should be using. There are guides, which is what Vizards book is about, a general guide. IMO I would use the cam kit as provided by the manufacturer and leave guesswork and theories where they belong and use tried and true solid engineering from the manufacturer.
lbs is a measure of force, lb-in is a measure of rate. I think you have it right in what your reading. Stick to the manufacturers cam card and go from there.
Interestingly enough if you look at the cam card for the cam I have versus the voodoo grind pn 60104, they use the exact same spring, same installed height and same seat pressure. The GM z/28 spring was 110lb seat pressure and about 325lb open pressure at max lift of .550, works very well with a variety of hyd and solid flat tappet cams, has for years. In actuality you just want enough spring to control the valves during operation, anything in excess of that just is wasted energy and causes heat build up in the oil.
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We will try them and see how they work.
Here is the cam card for the cam I have http://www.lunatipower.com/Product.aspx?id=1950&gid=277
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I think it would work fine IMO. I'd run some 1.6 rockers on that for a test. My Crane gold race rockers are adjustable, 1.5, 1.55 or 1.6. I think these alum heads are probably every bit as good as the ones you were looking at but have the advantage of less weight, probably better flow, smaller ports = better response, and of course the "BLING" factor of aluminum.
As for voodoo cams, not sure what your thinking about there pyro. Cam calls for 100lb on the seat at 1.750, so hardly alot of seat pressure. IIRC the open pressure is something like 250 or 275, so no it's not alot of spring rate. I was trying to get the isky circle track grind 201284/6 which has almost identical lobes but couldn't find it, so I went with the lunati, besides I think the lunati was cheaper anyway although the lobe center is 108 instead of 106. But what is 2 degrees amongst friends.
And yes I prefer tight lobe centers on street engines for better mid range TQ over say 112 or even 110LSA's. IMO it's better to have TQ hit early and hard IMO, it wins races. -
Actually they kind of lack at low lift. 28" of h2o which is the standard. Kind of weird, but if you think about it you have no vacuum at WOT. Not sure how that standard came about. A larger motor is going to draw more air than a smaller engine, but manifold pressure will still be zero guage no matter what, which is 14.7 psia at sea level and less than that at altitude of any kind.
I thought I'd try them just for kicks and grins, they certainly flow better than most heads and they are aluminum so get the weight savings, repairable and of course the WOW factor when you pop open the hood.
I think to take advantage of those flow numbers your going to have to run a cam with at least .500 lift. I'm planning on running a lunati voodoo with .507 lift, 238 or so at .050 and then I've got some 1.6 roller rockers so that should bump it up to about .530 or so give or take.
Just thought for the price he might want to check them out since they are about the same price.
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630.6 rwtq, Ford 9 inch, stock resplined axles, detroit locker, 4.56 gears, 29.5 x 9 x 15 slicks, ladder bars, coil over shocks. Absolutely no issues ever.
I have a jig to narrow 10 bolt, 12 bolt, 9 inch and dana 60 axle housings
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Busy working. Building an engine for the southern sport mod nationals in Abilene. I'm going to drive an IMCA modified in that race next month.
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There's all different combos from this guy on ebay, but I was leaning towards these most. 64cc chamber with 230cc intakes
I managed to find these. Liked the flow numbers and the price. I bought these yesterday.
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IMO when you see that and you check the align hone on the mains, you will find that it is off and that block will need to be align honed.
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Dr Hunt: Don't get so upset. Just pointing out the facts. Disagree on location of the temp sensor. He is likely not running Circle Track nor NASCAR. In NASCAR the engines are likely rebuilt after ONE race. What is the justification for running 230 to 250 degrees? Oil is not the PRIMARY cooling medium. The condenser is not MODERN and looks to be oversized for the application. Understand efficient radiator, proper water flow and adequate water flow. Pointed out a DIRECT experience with undersized GM type water pumps. The suggested source for VERY GOOD water pumps was IGNORED. Need more?
Fact is that 230 or even 250 doesn't kill the engine as long as the water stays in the block, pertains to everyday vehicles as well as nascar. That is my point. If you run a 22-24lb cap on your daily driver then it'll run 250 or 260 without hurting anything which can be mighty handy if you don't happen to see the temp guage or temp light come on right away! Oil looses it's lubricating ability if it gets too hot and will cost you an engine, which is why most top end road race cars monitor engine oil temp. But in this case the poster doesn't run the engine at that temperature for any extended period of time, in fact quite the opposite.
An engine typically lives longer if the operating temp is 180 to 200 degrees but closer to 200 which is why the manufacturers use 195 thermostats. Less temp typically makes more power because the engine heats the incoming air in the intake and heads, which is the primary reason for having temp readings at the intake rather than the head, although either is fine but the water at the neck area is exiting the engine and is the hottest of the two.
You can mod a stock pump for more flow by riveting or welding a circular plate on the vanes, been there done that and back in my days we rebuilt water pumps, starters and alternators. Actually the gasket for the back of a water pump is in a full gasket set for those of you who want to try that mod. A lot of attention is being given the pump, but no attention given to the drive mechanism. You can overdrive or underdrive the pump which is usually more cost effective than buying a $150+ pump. I have found that option much more effective both temperature wise and cost wise.
Stock pulleys overdrive the water pump and there are two sizes for the sbc long style pump, non a/c and a/c and come in v-belt and serpentine belt options. The a/c version is larger diameter and drives the pump faster for more coolant flow and is typically installed on vehicles with A/C and/or two package and is often seen in newer vehicles with aux. electric fans as well. There may be others as well offered from the factory that I am unaware of and there are many offered by the aftermarket. I personally underdrive the water pump by 80% using the Moroso 3 inch diameter crank pulley on all my race cars and I have no problems with cooling since most water pumps flow way too much to be effective. Yes, that is right you can have too much flow and not enough residence time in the rad, especially in an aluminum radiator!!!!
The serpentine belt offers superior belt gripping ability over the v-belt design. Both have their advangages and disadvantages. v- belt slippage can contribute to heating problems as well, but multiple belts offer a safety in case some road debris happens to take one out. Redundancy is the key there and is my point.
I see your point and agree for testing for a plugged radiator which is basically your suggestion, but brings to mind the thought of doing it right the first time or skimping and using used parts of unknown quality and serviceability. Not sure it's all that applicable to the poster of this thread since he didn't state that he bought a used radiator off ebay, but a valid point nonetheless.
Personally flow testing, especially aluminum radiators is a mute point as they significantly outflow any copper cored radiator hands down due to larger tube cross sectional area. Although packing peanuts would significantly impact that flow characteristic, but allowing that to happen seems rather inconceivable except in rare instances considering how much money a person typically invests in an engine. It's a healthy investment in an engine that should last for years and taking chances on used radiators is aking to shooting oneself in the foot, which is another point. Things cost money and it is troublesome to watch inexperienced people invest heavily into the engine only to have problems such as overheating. I am sure any advice is great, especially if it directly pertains to the situation at hand, and even if it doesn't directly apply to the thread.
I think there is alot of information provided here by alot of members and should be compiled and made a sticky by someone other than myself. Seems a good idea overall. Perhaps one our new admins will be up to the task.
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You know for $150 you can get a new cast crank. I'd opt for a new crank if it was me. You can get a forged crank for $350 or so which would be even better. My advice anyway, take it or leave it.
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Happy B day! What did you get, er, get yourself?
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Happy B day Ron, this is the thread that keeps giving and giving year after year!
How did you come up with that track width in the rear?
350 build
in Gen I & II Chevy V8 Tech Board
Posted
Yup, the metal shim head gasket, used by GM and still available, has a compressed thickness of .022 which will effectively give you a theoretical static compression of around 10:1. I didn't go that route, but instead used the 4 valve relief speed pro forged pistons so I'll bet it's around 9.7:1 or so. Not bad.
I second guess myself sometimes too, but at least I have you guys to tell me when I'm all wrong.