Ok, here's the cost so far into this top end project: $240 machine service to pressure test the heads, clean and mill .060 $100 machine service to clean and mill intake manifold .040 $0 workbench porting and polishing (not including pizza, cigars and beer) $170 porting and polishing tools, mandrel, sanding rolls, cleaning supplies. Purchased mostly from TA, some local. $370 TA 212 camshaft and lifters and stage one springs $215 TA stock valves $370 TA head and intake gaskets, hoses, timing gears and chain, thermostat, sealer, oil, heat crossover plugs, adj. pushrod. and other wear items and fluids. The machinst still has my heads, he is plugging crossovers and emmission holes, multi-angle valve grind, bronze wall valve guides, and assemble. I'll add that cost to this list when i get them back.
I've been visiting my machinist every other Saturday, he sadi today that the heads have the new guides and the hardended seats installed, they will be assembling them this week. Should have them by Thursday. WOOT!!!! ray:
Im in the same boat! they were just finishing them up this week but are closed over the weekend, so like someone else told me.. Hurry up and wait! also what is the finall cc number on the heads?
Hey Brian, hopefully i can answer your question about the final cc# on the heads this weekend..........best of luck with your build.......
Talked to the machinist today and looked at my heads.........new valve guides are in, hardened exhaust seats, sweet looking valve grind......they had to order the proper valve spring shims, will be in on Tuesday, then they assemble. Should have them by next weekend.
Got the heads back yesterday.... Will cc them tonight and calculate the static compression ratio. Also will list the cost of the work.
CC'd the heads tonight, they measured 40 cc's.........now to do the math for the new compression ratio......
I calculate a 9.7 to 1 static compression ratio with the 40cc heads, should be good to go with the 280/285 advertised duration. If someone can confirm the dynamic CR, that would be helpful. Here's an update on the costs: $240 machine service to pressure test the heads, clean and mill .060 $100 machine service to clean and mill intake manifold .040 $0 workbench porting and polishing (not including pizza, cigars and beer) $170 porting and polishing tools, mandrel, sanding rolls, cleaning supplies. Purchased mostly from TA, some local. $370 TA 212 camshaft and lifters and stage one springs $215 TA stock valves $370 TA head and intake gaskets, hoses, timing gears and chain, thermostat, sealer, oil, heat crossover plugs, adj. pushrod. and other wear items and fluids. $140 multiangle valve job $128 new bonze wall valve guides and install $152 hardened ex valve seats and install $60 plug emmission passages and heat crossovers
Money adds up quick doesn't it? TA 212 with 280* seat on intake will give 66* ABDC with a 4* advance installation, which gives 10.14:1 static for 8:1 dynamic. If your SCR is 9.7:1, you'll have 7.67:1 DCR. Give me your numbers again and I'll recheck your static compression for you if you like. I simply use the compression calculator at Summit: http://www.summitracing.com/popup/calcsandtools/compression-calculator ---------- Post added at 08:51 PM ---------- Previous post was at 08:49 PM ---------- I use this calculator to get your dynamic compression: http://www.wallaceracing.com/dynamic-cr.php
Anything from 8.5:1- 10:1 the TA 212 works great... it is not too sensative to compression ratio so do not worry... Tried this cam with both 8.5 and high comp engines and it runs great.
You could advance the cam install to 8* instead of 4* netting 62* ABDC for a DCR of 7.91:1 if you like, to get it closer to 8:1. Advancing your camshaft will lower the power band of the engine, however. For every 1* advance you move it 50 RPM lower (the reverse is true for retarding: for every 1* retard you move power band 50 RPM higher). So every 4* = 200 RPM, meaning you'd move power band about 200 RPM lower with an 8* advance assuming a 4* advance default installation point. TA 212 cam typically has peak torque relatively high in power band, at around 4100 RPM using 1 3/4" headers, TA intake, Stage1 valves, and port work with a 3* advance installation. Peak HP is around 5200 RPM with this similar setup. So with this same setup you could figure peak torque around 3900 and peak HP around 5000 with 8* advance. Lower these numbers if you're not using headers or Stage1 valves. So with stock valves and exhaust manifolds, probably a peak of 4800-4900 and 3700-3800 peaks with 8* advance. Power will come on strong around 2300ish RPM and will trail off noticeably after 5400ish RPM with the above setup (8* advance). If you don't mind lower SCR, keep it at 4* install and simply add about 200 RPM to the powerband described above to get your approximate power band. ---------- Post added at 09:14 PM ---------- Previous post was at 09:12 PM ---------- Even though this is true for most cams, why not milk it for the most power you can by matching the compression closer to the cam for the grade of fuel being used? :TU:
Being at 9.7 is plenty healthy for that cam.... I think many people spend too much time worrying about dynamic compression
Thanks Gary for the advice on varying the advance on the cam installation, and thanks for those links to the compression calculators. The Summit one is an excell spreadsheet that i saved to my computer. The dymanic calculator i saved as a link. And thanks to you Sean as well, for the confirming observation. I had wanted to have enough compression for the cam, but still run 93 pump gas, so i was shooting for close to 10, but not over. But the head cc's came in a little more than expected, probably because i smoothed and polished the chambers and also ground off the machining reference nubs. Varying the cam advance sounds like a fun thing to do, followed by trips to the Lapeer dragway for ET data. Btw, i don't think i posted the set up in this thread: 1 5/8 headers 2.5" dual exhaust, H pipe, glasspacks Muncie M22 4 spd 3.9 gear No AC Manual steering Manual brakes MSD ignition 34* by 2500rpm Tuned QJet TA intake And, oh hell yeah, the $$ add up quickly. But, for hundreds of dollars less than the price of outsourcing the heads alone, she also gets a new cam and lifters, not to mention all the wear items that get replaced on the install. Took a LOT of time. Next on the list......install and degree the cam.........and decide on the * of advance..........
OOOOHh yes it does add up quick.. now i understand what people are talking about, its much more then i thought it was going to be.. i can pretty much double my original thoughts in terms of money spent.
Yes it costs but I believe that you will be happy with the out come verses not following the info given and throwing it together and finding out what you did wrong and then the expense of trying to fix it a second time. You can see just by the fact of the pistons the shop used in your motor and what your car might have been like with them.
Steve If you advance the cam more than 4 degrees, take the time to check piston to intake valve clearance. Normally not a problem on a 350 but since the head was milled so much the intake valve is a lot closer to the piston. As you go past 4 degrees advanced that gap can close up in a hurry. The valve gets close to the edge of the dish.
