Clevo120Y

Hey people, I thought I would start another thread for the OHC heads I'm starting to work on. I setup a head today for testing, I had to make a new valve opening fixture for the 4L which took a bit of time but I got some base tests done before packing up for the day. First head to get tested is a stock 94AB and stock intake manifold (BBM) Head by itself, 1.84in valve, 3 angle seat cut. 50 35.31 100 57.37 150 88.73 200 121.52 250 148.44 300 173.54 350 195.72 400 207.48 450 215.09 500 216.38 550 217.66 600 219.62 Now I remember Dave putting up some results of a head before and they were quite different to these, I checked and recalibrated my bench and these are the results I got twice, maybe earlier heads flow less I don't know. Anyway I did 2 more tests with the stock manifold on, Test 1 was with the internal butterflies closed so that means running in long runner form. 50 34.93 100 56.54 150 84.14 200 112.15 250 130.87 300 145.16 350 157.23 400 164 450 167.78 500 170.16 550 171.44 600 172.32 Test 2 was with the internal butterflies open so that means running in short runner form 50 36.16 100 56.39 150 86.35 200 114.58 250 135.57 300 154.27 350 169.43 400 177.97 450 182.73 500 187.93 550 189.06 600 189.33 So as you can see the short runner flow is a fair amount better than in long runner, tomorrow I will start some mods to the manifold and test them, it will be aimed more at higher sustained revs like speedway and burnouts so 3000rpm and above. I will post some pics when I take some. After that I will start to port the head and will post the results, I have a head to do for a burnout car next week, it is a later EL tickford head with beehive springs like the AU so it must be a very late EL head, reasonable cam and a very good driver, I have seen him perform before and he pulls good skids, part of the deal is a big sticker on his car and he enters quite a few events so I have to come up with a sticker design as well, good times

I thought I would start a separate thread for the head port I'm working on for the race head I'm going to be doing for a proddy speedway car. This port is a C1A casting, and the results are using a stock standard crossflow intake valve, 1.8in single cut valve. The port has a 3 angle seat cut that is a little worn but still usable. So the first test was on the port as cast from the factory with the 3 angle seat cut, the second test is with the port ported and the third is with the port work plus the chamber work. this is the stock valve I'm using Stock combustion chamber and reworked chamber, not much needed here, just laying the edge over and blending to form a nice smooth shape, you have to take the point off the end of he swirl generator to stop pinging. This is the port work, hard to explain what I have done but most of the work is at the short turn and bowl area, I mapped the air velocity of the stock port to determine what material and shape needed to be used, the port responded well to being biased to the right. Here are the results test1 test2 test3 50 29.4 30.95 36.08 100 54 58.34 63.15 150 77.4 85.6 92.5 200 98.5 108.98 121.92 250 121.2 131.56 149.84 300 141.4 151.05 165.2 350 162.9 168.79 178.97 400 177.7 180.13 190.17 450 184.4 189.02 198.22 500 186.2 197.22 202.96 550 189.1 203 207.93 600 214.2 213.98 650 213.44 213.4 700 212.16 212.2 So as you can see the results are reasonably good, the chamber work plays a big part of the power potential, this head now has a flow potential of 330hp using the stock standard intake valve. Hope you find this interesting.

Hey guys, I need a breakdown on how all the sensors work, there voltage ranges, the affect on fuel and timing maps ect ect. Using an EB manual ECU as an example, can sensors be manipulated to "trick" the ecu and if so how and what does it do to engine performance, everyday drivability is of no concern. Please explain it to me like I'm stupid hahaha.

Let's talk ignition systems for our crossflows. I personally have had great success with the TFI dizzy and MSD 6al-2 programmable 6530 ignition system, I found that the features of this system were hard to beat for the price. Rev limit, burnout rev limit, launch rev limit, boost/nitrous retard and a full programmable ignition curve, you can make and save any number of curves to suit different fuel or race conditions, just upload from a laptop.

Lets share some cheap easy changes to get the most out of our crossies, I have a couple that I will post up later that I have been working on.

Hey guys, now that another race car that I developed the engine for is up and racing I thought I would start a new thread for it to update it's progress. This is another XF but in the production class which is the next step up from the street stock cars. Another carby crossflow but SO much more freedom in development, modified intake manifold, ported head, balanced assembly, aftermarket ignition, electric water pump, 350 holley (modified), roller rockers etc etc but must be pump fuel. So most of the stuff I have shared with you before but I will go over it again, this engine runs a 86da block, EF crank, 200 rods with 13cc pistons, ported XD head with 1.86in intake valves, 1.6in exhaust valves, yella terra adjustable rollers, head flows 212cfm. Comp is 10.5/1 with 6al msd ignition off XE dizzy, electric water pump, 1 3/4in long tube header. I ported the head, modified the intake manifold and built/modified the carb. I also speced out the bottom end but it was put together by the owner The cam is a solid flat tappet that the owner already had so all my calculations are based around that. Cam specs are: In lift 562, ex lift 571, duration at 50 in 251 ex 254, ICL 105 LSA 106.5 So here are some pics of the head, manifold and carb work.

Definitely worth a try for sure.

I would put a modified stock manifold in front of that, the air/fuel would shear off the short turns into the runners something cronic. But like the other guys have said, you got it so you may as well try it.

I personally wouldn't use that manifold, the transition to the runners are too square and would flow quite poorly.

I personally like the 465, great all round size and vac secondaries.

I also agree with stock oil pump, the race engines I built run the same "big" clearance as Ando and the stock pump has plenty of pressure. Ando will give you the measurements for the relief valve, I also do the clearances inside the pump, I run 1.5 thou cover to rotor clearance, that had Ando worried hahaha but all good in the hood.

Good to hear mate and great to see others have a go with positive results

No worries Gerg, I have one word for you that explains the down size in fuel jet, EFFICIENCY!! Your carb is now more efficient and your engine requires less fuel to make the same power, the booster signal will be cleaner etc etc. this is why when people say that if you have more airflow you have to add more fuel but it isn't always the case, an efficient motor will use less fuel for more power and that's in the forefront of my mind when I do my little experiments.

6-3-1 suit more revs is my opinion, more secondary volume. We have had this conversation before lol, I like the 6-3-1 setup.

Do you still need a fuel pump hole blanking plate? I can send one with your manifold if you want.

Ahhhh ok fair enough.

The EFI wagons had an external high pressure pump with a low pressure lift pump in the tank, you could probably setup the same thing without the need for a surge tank.

Will do, I was just looking at a manifold and I think I will knock something up, it will have 3 webber mounts so an adaptor to a strommy would be needed.

I'm considering the idea, I might look at putting something together just to see if it can be done properly hmmmm brain is going now hahaha

I have been getting into the speedway down here and it's a great form of motorsport, class rules make the development of engines a real challenge and that makes it very interesting for me. Anyway I was talking to a bloke who runs a crossy XF in the street stock class and he now has me building and developing his engines which is great, top bloke and just gives me free open slather on what I want to do engine wise as long as it's within the rules. The challenge was to make the car competitive against the newer injected cars that have a grip on the class but sticking with the carby crossflow. All the racers down here said it couldn't be done so the challenge was on. I have been involved with the car for 3 rounds, the first round was just some tuning and setup with the engine that was already in the car, setting up rockers, timing, fuel etc etc. the car went really well and finished in the top ten of a 24 car field in the final, he was a bit too excited with the extra power and reved her a bit hard and hurt the engine so he I got to build a new one for him, Full rebuild so I flowed the head, picked a cam that was actually smaller than what was in it already as I think it suits the engine and rev range better. Motor went together nicely no real problems, ran the cam in and raced it again next round. First heat I asked him to just take it a little easy and load it up to bed rings in and shit, he was happy when he came back in and thought it was producing good power lower in the rev range which is what I was after. Heat 2 he was having problems that it wouldn't make power under 4500 and we discovered that the dizzy had broken the center signal wheels pin, so the dizzy had advanced itself and made it run poorly, we missed heat 3 while we fixed the problem by repining the dizzy centre and got the timing as close as I could just to run in the final. Started the final in 12th position and finished 4th. Not bad for a new engine with no real tune in it yet. The car was dropped off to my workshop before the next round for me to go over the engine and build a new dizzy for it that won't break. Everything was micky mouse and no damage done by the broken dizzy. I went through and studded both the intake and exhaust manifolds to make things easier when pulling it down and putting it back together, set all the timing up again with a conservative tune because I couldn't make it to the track for that round and I just wanted it to be nice and safe/reliable. Well he finished 2nd outright in that round and was pumped with how the car performed, a couple of the faster cars of the region were at a different event on the same day so I still think we are about the 4th fastest car in the region at the moment which is still pretty good I rekon. Next Saturday we are racing in Albany again and I'm onto some more development work, I have done some flow testing on the stock aircleaner assembly and carby. The stock webber carb flows 261cfm and when you put the aircleaner on it drops down to 235cfm, it is the same with or without the aircleaner in the housing, what this told me is the restriction is the amount of air that can be pulled through the original snorkel, so I used a holesaw to make some extra breathing holes on the opposite side and had immediate gains, this is something that can be done to a stock car for nothing. The flow went up to 251cfm just by giving it more area to breath from. Next I will be cutting the top off another aircleaner housing and welding it to another base to increase the height of the housing over the top of the carb as this allows a taller aircleaner to be used and gives extra height above the carb which allows for better flow. I will also building a custom webber carb during the week for increased flow and hopefully the AFR meter will be here during the week so we can fine tune jetting at the track.

Thanks mate, I'm sure wombat will ring you if I don't make it down, he is going over to an ex modified racers workshop to set it up, graham mcsweeny if that rings any bells?

This engine runs the multi rib EF balancer, alt and a Holden PS pump all on the same belt. We have wombats street stock setup like you have said above.

Still thinking about the last meet, these guys are pushing there cars so hard, the amount of mechanical carnage every race is unreal, half the field comes in with blown gaskets and radiators boiling, one of the blokes car caught on fire in the final after leads melted and set the powersteeri game fluid that was going everywhere on fire. Great stuff

We are finally getting the car scaled and suspension setup in the next 2 weeks, thank god for that haha

I agree Ando an idler pulley is what's needed, I just have to get a rocket up the guys there to get it done lol