For you veteran engine builders out there I want to know how do you get the intake ports to match up dead even with the head ports? In all of my manuals it says you should always mill the intake when you deck the block or the heads you have to compensate by milling the intake also, so the ports match. [br]1[br/] Now the theme of my engine build is going to be EFFICIENT. I want to make the ports line up perfectly. The heads are going to be a set of GT40 that will be milled 2cc from the stock ratings. Also im going to CC them myself to try and get them to be the same via porting of the chambers. Now the port work is going to be left up to a local guy that owes me a favor. The last set he ported flowed 210/174cfm @ 0.500. Im also going to have them flow tested before he`s done im hoping he can get them all to flow evenly with each other. Luckly i know a guy who will trade me a flow test at the shop he works at for a set of EF springs that i have. [br]2[br/] The heads will be getting a set of 1.9/1.6 values and a 3 angle valve job. The intake is going to be a Weiand Stealth with the divider knifed edged a third of the way down. On top will be a 650 downleg booster Holley with a 1" spacer. Trick Flow Stage 2 roller cam with scorpion rockers. Its somewhat of a budget build most of the parts are used. And the head cost is still less than half of the cheapest aftermarket heads any input is appreciated . [br]2[/br] Edit: more info. Im going to try and shoot for 10.5:1 CR to run off of 91 octane which is the highest pump has available here. The car will be weekend street/strip. I will not be running a PVC system, instead i will run a breather tank. Im going to be playing with the ignition timing alot so im doing that to prevent any unwanted detonation.
For some reason i cant do a line break. So if a Mod can insert them id appreciate it. I tried forcing it with BBcode but it didnt work.
Im not a veteran engine builder, but I did do a gasket match on a 305 with a buddy. We matched the intake and head ports using the intake gaskets as templates. We then blended the new port into the runners about 2 inches. It was just a matter of 'bolting' the gasket on the intake and heads, scribing the outline of the gasket port, and opening up the ports to the line.
You need to edit your own text Just hit the EDIT button, go to where you inserted the br html code and hit the ENTER on your keyboard 2 times - that will put in a break.
Well that matches up the port up to the gasket which I know how to do. But when does the varying deck height take into play? Im using a 8.2 block but i havent checked it to see if it`ll need to be milled down. With a V engine that has an effect on the ports matching. At least in my head, i might be wrong. Someone correct me if I am.
The "enter" key on my keyboad is not working thats why i tried to force it. Im off to buy a new keyboard right now.
milling the heads makes the...intake mounting surface....wider. milling the intake make the gap even wider......i think they make a plate to take up the difference. ...Not an engine builder...
When you mill the block it actually moves the gasket surfaces closer together on the intake side. The block is at 90 degrees, cut off some of the top of the deck and the heads move closer together. This will make the intake bolt down higher on the heads causing a misalignment of the ports. You only take half of the distance milled off the block + heads off the intake. Example = if the total you take .010 off the block and .010 off the heads then that is a total of .020. you will need to take .010 off the intake face on each side and .020 off the bottom of the intake. I am almost positive of that procedure. I may be wrong and I will check with a machinist friend of mine to be sure. Or someone on here will be more than happy to correct me, LOL! How I have matched intakes in the past for track cars is to buy 2 sets of the exact same gaskets, spray them with copper coat, bolt the intake on the engine, toque the intake down then take it off. This will leave you a template to go by from the impression on the intake and head. Remove the intake and heads, port match them, clean them up and re-assemble.
^Thank you, thank you, thank you! Thats what i needed to know. God I love this Forum. I never would have thought of the templete, that seems like it would provid the best method to get the ports to line up perfectly and will make it easier to port. I know im probably overdoing it on this engine, I dont think itll be much of a gain on a mild engine like this. But every little thing help right?
K.I.S.S. It's always the simplest things that we over-think. This is genius! If you are willing to put in the time then go for it. How do you think the guys in the super stock classes get their rules restricted stock muscle cars to run in the 11's?
Thats what im thinking. Most of these arent even expensive, just time consuming. But i have plenty of time. I was just reading an article on Kory Keshembergs maverick and Hes runnig 11.70s with 348 rwhp. Now ive seen GT40s make 300rwhp with mild cams and just an gasket port job. So if somehow i can extract 48 more whp i know power wise itll have enough for elevens. But mainly im just concerned with building the engine and documenting everything to help others with their future builds. Also ill dyno it, theres a couple of places here where i can do it for $40. I know theres very few people on here that actually dyno their engines due to the price, but im very lucky to have cheap places around here so ill take advantage of it.
The mistake you're making here is thinking you have to mill the intake after milling the heads. Nothing could be further from the truth. After milling the heads, bolt em on the block, then do a test fit to see if the intake needs milling as well. Sometimes it doesn't. I've built three motors with milled heads, but only one of the three intakes needed to be milled to fit. The second motor I used those same heads on, the intake needed no milling to make it fit the heads.
I never said you have to. You can reread every statement I said in this thread. I just stated that my repair manuals state that you should when working on a V engine. I was asking how to get the ports to match up. And I got my answer.
Ok, whatever dude. In your original post, you did imply that the intake had to be milled too. I was just responding to that assumption.
Funny you mention that, I had Ram Air 3 heads on my GTO that were cut .040 and the block was cut .010 and the ports were dead on (easy to check with a Torker!).
