Bsa

Yeah thats y I didn't modify the stock intake. Thanks for all the info rob82 really got me thinking now. When I had my BMW I exterimented with the intake changing it from plastic to alloy and extended the runners and made the plenum smaller made a heap of difference with low end power which it was lacking it was the slanted 6 na. I think what your saying is correct the plenum does have a huge impact on the engine just trying to figure it out properly is the hard part. Iv drawn up 3 designs that I'll start making this week there will not be any progress photos untill completed as I kinda want to keep it to myself. Thanks everyone for the help sorry for reving a few people up sorry if I offended you.

Yeah I have

Iv been looking at a plazma man today and looked at oem 26 plenum the other day I'm going to have a look at a greedy plenum this week. Iv been drawing down runner lengths injector positions pipe sizes everything as I want to get this right. Iv been speaking to many people about how they have gone about it and where they went wrong also the positives. I plan on starting one this week and seeing how I go. My mate in newy will flow test and pressure test it when I'm done. It will be a plenum similar to the plazma man they have it fairly spot on tho I can see where it could be improved. When I get that right I'll move onto something new. At the moment I plan on just doing turbo inline 6s as that's what I have available to me. Roy you know what it's like to have a go at things when everyone is saying it's better this way so I think you know where I'm coming from by doing this. This thread has been a bit unforgiving for me and made me look stupid but typing on a key board is totally different to talking in person. If everyone was to meet me I'm sure people would see I'm not a idiot and that I'm on the right track.

i understand i will spend a lot of money to get it right. iv been looking over a lot of designs from big name manufacures and taking many aspects on why they are good just need to combine all the best designs into one. i agree its a hard task to take on and even harder to prove they work. but if i spend the 5 g on getting a few designs perfect then one day it will pay off. iv been looking into doing this for years and im now understanding how it all works. i plan on making 2 types one for your everyday where responce is needed and one for high rpm racing so short runners ect. yes i know it could be years before i start to actually get some where but im willing to do that. my tuner is being very helpful in everyway jez is keen to see it work but also telling me if im doing something stupid.

thats it as a complete setup. can be welded in if need be but this way makes for easy removal

you mean a pipe like this replace this bit where the afm was

I can do it not a hard job got one lying around that I made for my car

Sau will have to hold a boxing day soon Way the forums are going this month

If it had a service I'm sure plugs would be changed. Jez is right that list is your best option. Why was the timing changed it should be at 15 I'm fairly sure

You don't ask for skyline bits take your rubbers there and ask them to see if they can closely match the shape and size you will end up with 10 hoses from different cars but if they if it does not matter. If not buy heater hose and make it work. I had some hoses from a jeep all sorts of cars trust me much cheaper option otherwise buy Nissan

If you get a block honed to a fresh surface wouldn't that be like a new block? Why also would a new motor have 0 km cos it's a brand new engine that's why. The 30 block with a 25 head will smash the 26 block with tourqe and power

Do you know your afr readings? Could be dead fuel pump I would never put a second hand pump in waste of time really especially putting a pump in that's older then your car.

Pumps are cheap enough to give peace of mind just buy a walbro or 044

No worries let us know how you go. Could be just bad fuel and it's getting overlooked

Pull the plugs out re gap to .8 or .9 is he running stock boost? Also check all loom plugs are connected properly. If that still don't work check piping for rags most unlikely but never trust some one unless you know they are capable on rb engines they can be sensitive

Put a timing light on it to check. Your plug gap might be to big and causing a weak spark. But yeah like mafia said more info will help

Rito

Anyone?

Sure is more constructive good when you have people helping out and willing to see results

Yeah everything by the books want to do it right and don't want to fry a fresh motor either

Good idea mate I talked to the bloke that will flow test it and he suggested running it in the dyno first as that will give a clear indication of it working properly as it may flow well when tested but it will act different on the car due to pulsation and turbulence

I can make as many as I want no big deal. If a make one that works then im Charlie shiening ( winning ) if not I'll cut my losses and accept I couldn't do it

I'm not trying to get credit or a pat on the back this thread like the title stating where would people rather there power. And seeing as it's 3000 to 6500 the stock runners are perfect for the job why change something when it going to help me out? If the peak power was 4000 to 7500 I would of totally changed directions and designs this is for a street market not a racing market where people buy the best stuff. I'm happy to be told I'm going in the wrong direction but after everything iv ever read and been told there are 2 people telling me differently and I'm stupid for having a go that's not criticism that's just being a pain in the ass.

Found this on google its what i was trying to tell you but you wont listen When dealing with air movement there is a latent or potential energy Static Pressure (Sp) and a kinetic energy Velocity Pressure (Vp). Both pressures combined make up Total Pressure Tp. When you put a gauge on you invariably measure Tp unless you are smart enough to install a pitot tube.. So reading off a gauge can be a little deceptive in giving a true indication of what the air is air doing. But lets assume the air is travelling at say 30m/s open throttle into the plenum. Well you know that some of the air will continue as flume until it hits the opposite wall of the plenum, but a large percentage of the air will slow down. The plenum is therefore a cushion box and is designed to proportionaly raise Sp in relation to Vp which is especially desirable for when you have a manifold of pipes all requiring change in direction of common supply flow at different times, like intake pipes do. Of course the plenum will tend to knock out a lot of the pulsations coming back up the intake pipes too. If you haven't twigged yet, it's the difference in static pressure regions that causes the air to flow and it's friction losses and dynamic losses (flow separation) that reduce the flow. Now here's something worth pondering. A lot of plenums have a throttle body coming in on one end and the intake pipes lined up from front to back. As the air streams into the plenum the Vp starts to reduce and the Sp starts to rise accordingly, but this will favour a higher static pressure approaching the end of the plenum. To overcome this you really should taper the plenum so that Vp is relatively higher than or equal to that at the TB end, thus making the Sp more uniform throughout. The ends of the plenum should also overhang the first and end intake pipes to provide some cushioning and thereby helping the first and last intake pipes. What volume should the plenum be you ask? Well a factor of two (2) times the engine displacement is freely bandied about, as is 65%-80% for three cylinders (use two plenums for a six), 50%-60% for fours cylinders and 40%-50% for V8s, but really the best size is going to be determined empirically and I can really see a 6 litre plenum on top of a3.0 litre six using the 2 times rule of thumb LOL.. Some people swear by small capacity plenums to provide smooth engine response, others swear the opposite. The pundits will say the plenum should increase in size as you chase higher rpm, but this will make throttle response worse and low end power will suffer. Obviously decreased lag should occur with smaller plenums. At first glance a smaller plenum should offer higher plenum/cylinder differentials (P1V1= P2V2), thus better flow and more impedance to blow back during valve overlap, an advantage when using long duration cams. But also consider there is less volume and the suction stroke cylinder may be grabbing air from the other pipes/runners, thus reducing VE overall. This calculator actaully has some thought behind rather than rules of thumb. Mind you it was only a fleeting thought. Boundary layers ppfft who needs them.

Well tell me share to the group rather then being negative if you can help me and other people out then y not do it that's y these forums are here to help people solve problems not shit on them when they come up with a new idea and having a go.