4g63 concrete filling

I am inbetween doing concrete block on the 4g63. Been doing some reading and checking out different methods which seem pretty straight forward. I know if doing a full fill some work will be needed on the head to still run water through it, for 1/2 or 3/4 fill can still run waterpump or electric waterpump to flow through the block. Looking for 300hp per cylinder atleast. I am not versed in the concrete game and looking for some solid advice. Ive seen wet blocks do good numbers and live. Engine will be with aluminium rods, ive been reading about also using looser ptw clearances once on a full fill block.

My drag engines that ran on C16/Q16 were half filled. I used the moroso block filling grout and found that to be a pretty effective product that is easy enough to use - https://www.moroso.com/moroso-shop-browse/engine-block-filler/. You can fill them to, or just above the bottom of the water pump recess. I never really did a back to back test with filled vs unfilled so I can't really quantify exactly how much more power you can support on a half filled block, or if it'll make more power as a result of reduced flex in the bores but it can't really hurt either.

For our methanol engines I ran the block filled to the deck surface. The benefit is that you're now getting the concrete where you really need it most - Up near the top 1/3 or the bores. The downside is that this clearly is only suited to a dedicated drag engine and requires significant care with warm up and managing temperature during a pass. It's personal preference but I still ran water through the head and had a small electric pump and a reservoir. It didn't include a radiator for simplicity and weight savings but this did give me a convenient way of monitoring temps. To do this I made a fitting that entered the front of the head between the cam gears where there is usually a frost plug.

I never changed my PTW clearances for a half filled block on gasoline. I tended to run slightly looser clearances on methanol anyway but nothing wild as the fuel tends to keep the piston crown temps under control and you're not running the engine for extended periods either.

Thank you andre for a response, when you say the bottom recess of the waterpump port you mean the port to the exhaust side of the block with still maintaining the oem style waterpump? The car is going to be a dedicated drag car only so even if i full fill the block i was keen on knowing how to still allow the water to pass through the head, as you mentioned the part with the core plug i will look into that. Well we are keen on running e98 fuel so i will factor in that to the equation. The only question i have to ask myself is if id be doing a half fill or full fill. With your experience will you prefer a wet block over this as ive read that the 4g63 block is proper rigid to handle the stresses.

I'm talking about the port for the factory water pump, closest to the exhaust side and just above the balance shaft. I would fill to about half the height of that opening by placing race tape over it. Then when the grout was set I'd profile it using a die grinder to promote flow through the water pump.

It's a coin toss for me whether you completely fill or half fill. The 4G63 block is pretty stout even unfilled so it depends on your power aims. I've run over 1000 whp with a stock block. Keeping water in the block gives you a lot more flexibility if someone wants to hang you out to dry on the tree as you don't need to worry about if its getting too hot. E98 is a better fuel from a cooling perspective than gasoline but not as good as methanol. So for E98 I'd be inclined to half fill the block, not withstanding the fact you haven't mentioned power targets which will affect the decision.

Good day andre. As you mentioned the methanol the tuner is getting us on that train currently as he believes it will be the best option for our goals of 12-1500hp. We have done the block to half fill and awaiting to take it machine shop. We are running with some wiseco hd2 pistons so generally looking at around .004-.0045" ptw and have our gapping to suit. I really appreciate your support and guidance on the topic. Ill be keen on hearing from you throughout this build process

Yes at that power level I'd be half filling the block at a minimum and towards the upper end of the range I suspect you'll improve block reliability with a completely filled block but only time will tell. A lot will also depend on your tuning specifics too and the peak cylinder pressures you achieve. I would suggest you target slightly looser clearances if you're targeting 1500 hp too - I'd suggest 0.0045-0.005" would be more in line with your application.

Quick question on this, was on the dyno tonight with another build, e98, wet block. We had water pressure sensor on the radiator and was seeing 10-13psi unfortunately we had a core plug pop out by the no4 cylinder on the exhaust side. We popped in a new one sorted out the waterpump as we saw a leak, we swapped the sensor to install it where the thermostat housing is on the oem coolant gauge sensor spot and we made sm pulls and saw a increase to 50psi but the limiter cut at 50 because that is wat it was set at. We decided to call it quits because its not a realm we were familiar with. The car saw 912 hp at 42psi. No water was pushing out the resevoir. Prior to the dyno we pulled the valve cover and retorqued the arp 625's. The front 2 bolts gave us a 10ftlb turn to 100ftlbs frm 90. It was all initally set to 100ftlbs. All others were within. Please advise what do you think.