Guest Locutus Posted June 14, 2001 Share Posted June 14, 2001 I have found these heads, very low price they look very good have a recent valve job. The casting number is 14102193. All I can find is they came on 87-up 350. I think they came off a 1988 Trans AM w/ 350. Does anyone know of the CC and if this a decent head for a mild 350. Around 350 Hp is the goal. Mike Quote Link to comment Share on other sites More sharing options...
DavyZ Posted June 14, 2001 Share Posted June 14, 2001 Mike, I know the 305 came with some small CC heads, like 58cc. That bumps the compression way up to about 10:1 on an 8:1/8.5:1 motor. The 350 heads...well...I'm not sure they are 58cc or 64cc. Sorry--someone else should chime in. Those heads are supposed to flow better than say a stock 350 with 76cc smog heads from the 70's. David Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted June 14, 2001 Share Posted June 14, 2001 Are you only doing a head swap or are you rebuilding your engine from the ground up? Your final compression depends on the pistons currently in your engine (dished or flat tops). If you're engine currently has flat tops (doubtful-they are probably dished if its a factory engine) & all you do is swap the heads-you're gonna end up somewhere in the 11.9:1 range. What you'ld need to run those 53cc heads is a 30cc dished piston; this would allow you to keep your 8.5:1 ratio. You'ld need 20cc dished pistons to reach the 9.5:1 comp.ratio. Chances are you have dished pistons-Find out from a local dealer which pistons were used in your engine (what their DISHcc's were) then we can have a better go at squaring away at what your final comp.ratio will be. Also-you need to be sure your camshaft is compatable w/the higher ratio. Just because you have a higher ratio doesnt mean your engine will improve-if your cam is too mild/you'll run out of power before the comp.ratio has a chance to really kick in. Remember: Dynamic Comp.Ratio (While the engine is running) and Static Comp.Ratio (while the engine is not running/not moving) are not one in the same. You'll definately feel a boost by putting those 53cc heads compared to what you have now, however-if you dont replace your cam to match the heads/your engine will run out of high RPM HP before the engine actually reaches its peak potential; which those heads are designed to reach. The 305 & 350 have the same con.rod/piston conpression height-so they should swap, but I'ld wanna talk to a local machinest knowledgeable about making such a swap before buying those heads-ask about all clearance issues. Hope that didnt sound like a bunch of circular double speak? Kevin, (Yea,Still an Inliner) [ June 14, 2001: Message edited by: Kevin Shasteen ] Quote Link to comment Share on other sites More sharing options...
Guest Locutus Posted June 15, 2001 Share Posted June 15, 2001 I have TRW Forged Flat Top pistons. This engine came in the car when I bought it. I am not sure of the current cam but I plan on buying one to match my setup. The model number on the piston is L2256 030( they are .030 over). The data I have on these pistons is head cc and compression ratio. 64cc = 10.9-1 70cc = 10.25-1 76cc = 9.6-1 I am also going with TPI so that is another reason I am considering these heads as they came off a TPI engine. The heads that were on there are 462624. Talking to local machine shops they all said these are lousy heads for a performance engine and that they were very prone to cracking. They are also 76cc heads. The only good thing was they have 2.02/1.50 valves. Is there any other info you need? Mike Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted June 15, 2001 Share Posted June 15, 2001 I have heard several GM heads were crack prone including camel hump fulie heads. I do also know that the crack if not serious can be repaired rather easily by a competent shop. Have a pair of double pump angle plug heads I used for three years that are cracked repaired with no ill effects! Only recently swapped them out for Edlebrock aluminum heads in my Z. By the way they perform just as good as my RPM's. Only difference I see is the weight loss going from Iron to aluminum. Mike Quote Link to comment Share on other sites More sharing options...
DavyZ Posted June 15, 2001 Share Posted June 15, 2001 I doubt I'll be able to find some camel hump heads at the yard, but I'll try!!!! That would be the bomb! With the small cc heads and good flowing characteristics, I should be about 300-350 hp! David Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 16, 2001 Share Posted June 16, 2001 Try this website: http://www.chevymania.com/casting/HEAD.HTM They have table of casting numbers and what info they could find about them, while they only list flow on a few of them, they do mention that those your talking about (462624) are indeed prone to cracking and are 76cc heads. I wasn't able to find the other number you mentioned in this chart, although somewhere I had another listing and if I find it I'll post it. Good luck on it, Lone [ June 15, 2001: Message edited by: lonehdrider ] Quote Link to comment Share on other sites More sharing options...
DavyZ Posted June 16, 2001 Share Posted June 16, 2001 BTW, my cracked heads are 76cc smog-job heads. Lenster and I are going to the local wrecking yard this weekend to see what we can come up with David Quote Link to comment Share on other sites More sharing options...
Guest Thurem Posted June 16, 2001 Share Posted June 16, 2001 The killer move is to just get some new Vortec L31 heads, I think they are only like 425$ brand new with valves and springs, which is probaply less than machining an old pair of heads. Thats an easy 400 hp with an intake and cam. Jim Pace and Scoggin Dickey have them. Thure Quote Link to comment Share on other sites More sharing options...
DavyZ Posted June 16, 2001 Share Posted June 16, 2001 You are right--however, I have already invested in very nice valve covers (I would have to go centerbolt with the Vortecs I believe) and also I would have to machine my intake manifold to accept the new mounting on the heads. I don't want to shell out anymore cash. If I was doing this all over again, the Vortec heads would be at the top of my list for a budget build up anyday. David Quote Link to comment Share on other sites More sharing options...
v8260z Posted June 16, 2001 Share Posted June 16, 2001 Competition Products in Wisconsin sells World Products SR torquers for 425 to 450 a set complete. I ran these heads on my car for five years with no complaints. They kill the double humps and the late 80s in all aspects. You also have options on chamber sizes and dont have to settle for the 30 year old technology that you would have to spend close to, or more than that amount on to set up a reliable a pair of heads. After all that money spent you've still got junk yard heads that aren't near as durable and wont build as much power as the SR's.For 100 t 125 more you could get the Sportsmans. they are usually a couple hundred cheaper than JEGS on heads and alot of other parts ,and JEGS is usually tough to beat on prices. Quote Link to comment Share on other sites More sharing options...
DavyZ Posted June 16, 2001 Share Posted June 16, 2001 I'll look them up--thanks for the tip! David Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted June 16, 2001 Share Posted June 16, 2001 Mike, Those figures for Comp.Ratio's on your .030 flat tops are the piston mfg's suggestion for a slew of possible camshafts that would compliment said pistons. Since the piston mfg has no control over which cam an eng.rebuilder will be using then the [suggestions] are merely their [averaged] figures to determine Comp.Ratio's...now, if they were rebuilding the engine-then we'ld know their rules were followed and there'ld be no problem. You already said you're not sure of the camshaft currently in the engine-so this leaves us w/an unknown variable. The other side to this is we also dont know if your eng.block has been deck milled-so that also leaves us guessing as to the static comp.ratio (based on the Block Deck Height-being decreased if it were milled then this would increase comp.ratio). The next variable is-we dont know the piston comp.height of your piston; since you have the piston's part# you can call the tech line & obtain that info. Knowing the piston comp.height would also tell us what Connecting Rod Length your engine currently uses. Factory Piston Comp.Height = 1.560 for a 5.703" Con.Rod while a 6" Con.Rod would incorporate a Piston Comp.Height around 1.2something. These are the unknowns; your cam profile, piston comp.height & connecting rod lenhth along w/not knowing if your block has been decked. For my assumptions I'll consider your block to be factory stock, the piston comp.height factory stock & the con.rod also factory stock. 1.74" = 1/2 Stroke of the 3.48" 350 SBC 5.703" = Connecting Rod Ctr-to-Ctr +1.560" = Piston Comp.Height ------- =9.003" (This is called the Assembly Length) 9.025" Block Deck Height of 350 SBC -9.003" Asseembly Length ------- =.022" Block Deck to Piston Deck Clearence +.038" Head Gasket [Crushed] Thickness ------- =.060" Quench (or Squish) at TDC Take the Quench & convert it to Cubic Inches by the following: 4.03^2 x .060 x .7854 = .76533 cu.in; now take that figure & convert it to [cc's] by multiplying it by the convertion factor of 16.387 as follows: .76533 x 16.387 = 12.54cc's This 12.54cc's is what you'ld add to the Combustion Chamber [cc's] of whatever cyl.head's you choose. Inorder to determine what cc's Cylinder Head is required-we need to know when your Intake Valve closes ABDC (we need the .006" to .006" Intake Lobe Opening Bank Seat to Intake Closing Bank Seat figures); its actually the Intake Closting Bank Seat figure we'll be using. This will tell us how much Cylinder Volume remains in the cylinder after the piston has moved upward ABDC in relation to crankshaft rotation-in degrees. (The Intake Valve almost always closes ABDC-that is why we need that specific figure). So, not knowing what cam you have-I'll merely give you the average of what I came up with that you'll need. Based on your ideal comp.ratio you want. IC = Intake Closing. IC = 71*ABDC 53cc Cylinder Head Comb.Chamber +12.54 Quench in cc's ------- = 66cc Final Combustion Chamber cc's = 11.8:1 Static Compression Ratio *This requires Race Gas* IC = 62*ABDC 63cc Cylinder Head Comb.Chamber +12.54 Quench in cc's ------ = 76cc Final Combustion Chamber cc's = 10.4:1 Static Compression Ratio *Pushing the Pump Gas Limits* IC = 50*ABDC 70cc Cylinder Head Comb.Chamber +12.54 Quench in cc's ------- = 83cc Final Compression Chamber cc's = 9.6:1 Static Compression Ratio IC = 36*ABDC 76cc Cylinder Head Comb.Chamber +12.54 Quench in cc's ------- = 89cc Final Combustion Chamber cc's = 9.05:1 Static Compression Ratio If your shooting for a 350FWHP choosing a head w/an intake port of around 190cc-200cc should work out great for you. The issues you need to nail down are-Block Deck Height, Piston Comp.Height (which will tell you Con.Rod Length) and your camshaft closing rate (Seat to Seat-usually measured at .006" to .006"/intake lobe openine bank to the very same intake lobe closing bank). I really enjoy playing w/these numbers. I also really appreciate this site/because of your questions (now & past questions) I have forced myself to learn things I've never even considered; much less even knew exitsted! Kevin, (Yea,Still an Inliner) [ June 16, 2001: Message edited by: Kevin Shasteen ] Quote Link to comment Share on other sites More sharing options...
Guest Locutus Posted June 18, 2001 Share Posted June 18, 2001 Well I have learned alot from this but I still need info on those heads. At 100 bucks for the pair they are a really good deal since the are fresh out of the machine shop. Especially if they meet my HP goal and they mate well with my TPI. Does anyone have any info on the heads so we know what the CC and the runners are? Mike Quote Link to comment Share on other sites More sharing options...
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