Peppy's Build Thread

[JVK]

Those die grinding tips have done some work . All I can say is that you and your dad are on the ball and you should be proud of your old man, He has taught you well and obviously you have learnt

about patience and being thorough as well. Threads like this are pleasure to view and follow with anticipation of the final result.

Good job guys.

[Peppy_t92]

Awesome work mate love seeing someone doing all the work himself instead of just handing over cash to a shop!

I should send you over a single cam 4 litre head to port and I'll test it out on my motor haha

Sent from my iPhone using Tapatalk

I think we have a heavily ported SOCH head here somewhere, with a big Cam, might be able to sweet talk dad into finding it, from memory it still needed some finishing off Edited 17/03/15 08:47 AM by Peppy_t92

[Peppy_t92]

Haha they sure have JVK, I think I owe him some new ones, Hare and Forbes have a 5 set of the 3" ones for like $100 -_-...

Thanks for the kind words JVK, he really gets in a zone when he's thinking about it, it just seems so natural for him and is a pleasure to be able to ask all the dumb questions under the sun and he will happily answer haha I hope it comes together fairly smoothly and we see some good results

[turbotrana]

There is a pic floating around comparing the stock chain and I think an Atomic one. The stock one is alot weaker. There is also a pic of a failed tensioner. I don't know what the solution would be to improve on the tensioner but I would look into it for my build. Maybe improved oil feed to the tensioner or hardening of the tensioner maybe.

[Skids4kids]

Atomic do a improved tensioner also.

[Peppy_t92]

Hey guys, it has been a pretty long two weeks working afternoons and over the weekend on the intake side of things...

It was my plan to use the FG intake manifold but dad wasn't convinced that it would be the best option... We looked over the design of both my Bf one and the FG one, how they mated up to the head, if we could get into the runners to clean them up and how much meat was on them... While looking at that we also looked at the intake port on the head, dad went through some ideas and we decided to leave my head alone and test some different theories on the spare head again...

Firstly did a flow test of the standard port, it flowed quite well, dad again compared it to a heavily ported VN head, it flowed a maximum of 158.7cfm@10"water or about 262cfm@28"water

Its a mess, I'll neaten it up on a program I have and include some graphs when I get a chance

We went off the basic theories that I spoke of in my last post, short side, roof, throat, guide boss, flow testing it along the way, we ended up with a massive port that took over 2hrs to port, lost flow down low and only gained 5 or so cfm up top... Confused we looked at it abit more thoroughly and used the pressure gauge to map out where the high pressure points were inside the port again, to find that instead of the airflow taking the general route of the short side up to the roof, it was actually coming from the far side of the valve through to the floor!! Obviously this is why we're spending the time to develop the port...

Std port compared to the Big port

So we still had 3 usable ports on the other head, slowly tried different things, to come to one that worked. There's not much info out there of what people have got out of these heads, Dinomite performance claim to have a CNC head $4895 complete with std valves flowing 295cfm@28" of water... This is very high compared to the Std port that I flowed (262cfm)... It's hard to compare two different flow benches it's like comparing dyno's, it also has a lot to do with setup, which dad has taught me to be absolutely critical, the head is leak tested each time it's put on the flow bench and we use a plastic bore the same size as the bore on our blocks and mark the head so it goes back in the exact same spot each time, to achieve accurate results... If you use a bigger bore then std you will get in-accurate readings as there's more room for the air to flow around the valve then when on the motor, so you basically try to achieve a realistic simulation as when it's sitting on the engine... Anyway we got to a port design that flowed the best we could achieve and weren't making any gains from porting it further, a few calculations using a spreadsheet that dad made up and it revealed that the choke area was actually the curtain area of valves, so no matter what you do you literally can not flow any more air through that sized area. This worked out well because he didn't actually have to take much meat out and only took about 30-40mins on the one port...

So we picked up a little bit of flow in the lower lifts but picked up quite abit at the higher lifts, seeing a maximum of 171cfm@10" or about 286cfm@28" which is about 12% extra flow over the factory port... This was achieved only by opening up the bowl, slightly lowering the short side and lowering the floor about 1.5-2mm... And in my opinion that's a great achievement...

Made a mould of the nearly completed port to measure the cross sectional areas every half inch

Back onto the manifold... We bolted up each manifold a std port to compare before and after..

This was at 0.450" lift which is closest to max lift of the std cams, revealing that the FG manifold flowed only about 5cfm better then the Ba/f style manifold.. Dad still thought that there was room for improvement with the BF manifold, so the work started, took it apart and you can pretty much get to every spot along the runners which you can't with the FG one without cutting it open...

Tested the bottom half of the bf mani and it actulally flowed quite well, obviously the plenum was a huge restriction, so we have cut up the ports/dividers on the top half of the plenum to basically make it an open plenum. Now it should be general knowledge that a tapered runner works well to speed up the airflow, we did some calcs with a program and it clarified this, so we also joined the two seperate runners on the bottom section of the plenum

Dad made up a plate to flow the manifold alone

We're still working on the manifold but some progress tests show that it is already flowing better the the FG manifold without richen cleaning it up, I.e sharp ended and stuff, so it's looking positive, I can still use my Process west fuel rail and I'm even going to stick with the PW throttle body relocation for now, so it saves some fab work if I was going to use the FG manifold.

I'm still trying to stick to my schedule so I dummied up the motor to measure Piston to valve clearance and also completely measured the cams while I was their using a Cam analyser program. Basically taking a reading of lift every 5 degrees of crankshaft rotation.. So I can say that the BF mk2 cams are 204/206 duration @ 0.05" and 0.428"/0.434" max lift... The centreline was hard to measure as the stock cam gears are obviously controlled by oil pressure, I got readings of 96* intake and 134* exhaust, the program calculated that it would be about 115* when the gears have pressure

we pulled apart a spare cam gear that was laying around, quite interesting but not too technical, I'll have to have a play with them in the tune, hopefully I can get some pointers (jet? Wombat testicles? Or Whatever your name is this week haha)

While I was there I put a set of BF taxi cams in to measure, they were 194/201 @0.05" and 0.434/0.434...

I'm going to see Brad at Atomic, about his HD chain, tensioner and dad doesn't like the stock flex plate, so I'm up for one of his ones aswell.

I got a Nizpro Exhaust, seems alright, could do with abit of a clean up on the dump flange but should go alright

Thanks for reading

Joe

Edited 30/03/15 11:01 PM by Peppy_t92

[k31th]

loving the write up mate.

[barnz]

That's quite interesting about the bf vs fg manifold. Are you going to fab your own upper plenum for the bf manifold?

[Peppy_t92]

No I'm gonna stick with the stock upper half, I have just gutted it out so it's essentially just an open plenum, looks stock, and don't have to modify any of my boost pipes

[JETURBO]

A FG manifold flows aprox 275cfm

A b series flows aprox 270cfm

So dont go to far as itl be a non gain situation on a stock intake, typical knife edging dividers are not always a good thing as well as polishing the surface to a smooth mirror is also a loss, you want to promote as much tumble/swirl as u can and taking meat off is not always to a gain situation....

^^^ whose this bloke hahahahahaha almost bang on what I said huh

Loving what you're doing joe keep it going

Bang for buck yep stick it out on the top half but if u got a few coins go an aftermarket plennum ( hypertune ) imho

Anytime on the tuning bud !