pf.

If I was aiming at say 10k I would be better off using the 25 or 26 head as the air speed of the ports would favour dual valve intakes. This would also increase costs immensely as I would not only need to spend more on the head but also more on the rotating assembly as I would *want* a fully counterweighted crank. Revving the engine into 10k and past territory would also mean I would need to spend alot more on the gearbox for a small percentage gain over a much cheaper 8k rpm build.

I will also try and get some port flow rpm and power estimations from some guys on another forum but I won't do that until I have pics as they will want pics.

Ok I have been going slow with the build I got the head back before machining to bolt it up the block is in my backyard atm I just setup my engine stand at work so I will be taking photos soon. I will make a new thread soon and leave this one here for tech discussion. I will say a engine needs air fuel and spark it gives no farks for how many valves are delivering the air/fuel to it. My head can be flowed for 350hp with 1mm oversized valves so I roughly know that it will need to spin at 8k maybe a little more to make that. My cam choice will be made for about 8k with a 2.6l (due to bore size) engine at 8k I think I will need to limit power to about 320 330 to stay just under 8k rpm. There is also the points that I made earlier in the thread about the 2v head being vastly cheaper and easier for me to work with. If you have not make sure you read the quotes on the first two pages as these points made by a pro engine builder are quite true. The build thread will start when I get time to move my engine the head is bare so ill just be mocking up for a while. I also don't have much cash so progress will not be overnight

Yea pretty much as long as you keep the engine over a certain rpm it will be responsive as f**k.

Look guys I can try and make a engine that has 11ty hp (which is next build) but I want to do this I have no care for how big my cock is.

I am a mechanic guys I have been involved with and have driven very fast cars I want a turbo yes but I don't froth over turbos like some. I don't mind having less power if I can use the power I have IE: racetrack style torque profiles. I have seen rb30 heads that flow enough for 330hp which would want my engine to spin at about the mark I am looking for 8k which is where I will be shooting. My engine stand comes soon dedicated to this build pistons are next $700 ill be contacting crankshaft rebuilders for a price to do the crank and I am thinking 26 rods. The head is back to me before machining so I can work out belt's and other little things a mate just blew to 30's at the mattsuri comp so ill be having one for bolts and other parts.

The reasons have been mentioned in previous posts but ill give you the cliffs version. There is no point of having more flow if it is not required the 30 head will be cheaper and provide me with all I need.

I don't care if this does not make 11ty billion killer wasps I still don't understand what the fuss is over peak power figures ffs. I have no care for dick size contests the engine I will build will be plenty fast for my needs. Also this is the n/a section of the forum not the turbo section so why are you intent on annoying me with turbo this and turbo that.

I am not building a turbo engine. As for bottom ends you have no idea I will be using different pistons as the 25 pistons will drop the compression the head is bent so after machining I hope to see near 12:1. Con rods will be changed other than that the rest is identical thinking AM forge I beams or peen'd and machined 26 rods"..

Ok a bit of an update head was checked by me and was bent it can be straightened. The straightening will increase compression greatly but he 25 block will drop it greatly so I have some numbers to play with So far the head is going to cost me about 2500 I plan on spending 2k on the computer and ignition so to come under the 10k mark it leaves me with 5k for block and fuel system. Costs will blow out so I have to play it safe with my money. The head price is service,porting,machining and a cam.

Was going to work on the head but got pissed instead so monday will be the tear down then ill have to tear the block down next weekend.,

Already got one bro but the build on that will be epic when I can afford it. The 25/30 will be turbo and forecasts are in the region of 30k for that build the 30/25 will be cheap as possible porting and chamber work will be the big cost.

Lol the 4v vs 2v vibe i'm getting from your post is high

Ok it is a good amount but it is not in any way remarkable look at the hp per cc it is fairly average considering you can buy a r1 tune it and make near 200hp. Also the e36 BMW's can make 300hp with a few mods the xr6 falcon is pretty much the same engine from the xf's just with 4 valves per cylinder. What is the hp per cc or ci of a xr6 compared to some older cars there are some that do near the same.

Now back on with the build I will be tearing the head down tomorrow or saturday will post pics.