TVIS 4A-GE 200BHP N/A Project

[KPARRIS-JONES]

I finally got the Water Junction off!!!

Was a complete PITA but now I have the wondrous problem of removing the frikkin' studs that were left behind. :censor: :

[4afte]

yeah, those studs, they look fun. not

[KPARRIS-JONES]

Can't wait to get at them!... <_<

Put the PAS Pump into its second coat of Gloss Black;....

....and the Igniter and Resistor are both in their first coat of Metallic Pewter;

B)

[KPARRIS-JONES]

Finished painting the Igniter now, here are the results:

I'm very pleased with the colour, and it has a high contrast against the black. :D

[KPARRIS-JONES]

Went out 40 minutes ago convincing myself that I didn't need to spend money on a hot dip, but after a few caps full of degreaser and wire brushes I had to give up. That scud is just impossible to remove.

Where the hell have you been driving this thing Leebo!? Looks like you took a short cut through some Tar Pits!

[4afte]

ah good old UK road gubbins. doesn't come from anywhere but gets stuck everywhere!

[KPARRIS-JONES]

So true!

I have found the 4A-GE to be a generally oily engine..... Maybe the grime seals all the leaks?

[leebo]

Went out 40 minutes ago convincing myself that I didn't need to spend money on a hot dip, but after a few caps full of degreaser and wire brushes I had to give up. That scud is just impossible to remove.

Where the hell have you been driving this thing Leebo!? Looks like you took a short cut through some Tar Pits!

alot of that was from a classic case of "forget the oil cap"..... and dirty country lanes.... but in all fairness that extra layer of skummy stuff makes this project more worth while

[KPARRIS-JONES]

And now for another update. I spent the day with a mate at college making up the adapter plate to make Valve Lifters.

The fake Cylinder was made by 3mm thick mild steel which was rolled, welded, filed and the painted. It has two plates, one on either end, which were cut to size and then chain drilled. They were filed and welded to the FC to make the adaptor we needed to get it onto the flow bench. There was a little more involved including some work on the lathe simply because we fancied being more precise

I fitted up the Valves for one cylinder so that we could then make the lifters. Using 7mm thick, 180mm long and 55mm wide steel plate we drilled the two holes to bolt it into the Camshaft retaining cap threads, and then we drilled out the bolt holes for the lifter bolts. The holes for the lifters were drilled at an angle of 22.5 degrees (half of the 45 degree angle the Valves enter in at) and then Threads tapped into them for our lovely 17mm bolts to go through.

We set up the adapter to the Cylinder Head with G-Clamps and then put on and zeroed the feeler gauge to test to see how well it worked.

Lifter bolts - we tighten/loosen these to adjust the Valve Lift, basically it allows us to calculate the flow rates at various valve openings incredibly precisely:

And we finished waiting for next Monday when we go to Castle Combe and get it on the Flow-Bench.

Which brings us nicely to the really technical bit... which I'm too tired to explain. But I do have the Excel Spreadsheets released by Power-Flow for the bench which do all the calculations for you once you input a few simple values obtained from a quick test on the bench. It's mind boggling stuff when you start but we're getting to grips with it and we will only really be able to tell when we actually get it onto the bench.

For now I'm looking into a combined cradle of dry sump and main caps which is ridiculously expensive however will allow us to rev to the 22000RPM I was hoping for to make the 300HP. It's looking to be about £5.5k for that excluding oil pumps.

I also have the dimensions for the ITB's which will fit across the quite frankly massive ports - 50mm at the Trumpet, 48 at the Butterfly Valve and 45mm at the Port which is honestly huge. It's gotten to the point where it's just flowing so much air that we need them very short and very wide. However, to be more precise I am using TVIS as a template and mocking up some spacers to see how the length of the intake tract affects the flow rates.

Hopefully I'll start to port out the Cylinder Head within the next month or two!

Until then I'll keep myself busy by putting in the oil restrictors in the Deck and blanking off the Distributor shaft.

KP

[PaulinhoT]

A very nice update, it's all looking really good

Take your time and enjoy the results :D

[KPARRIS-JONES]

Cheers Paul, I'm definitely taking my time with this one, especially seeing as everything I've done so far has been free and I need to keep it that way for as along as I can

KP

[KPARRIS-JONES]

Ok we have learned from previous mistakes and we will be at Combe next Monday to get her onto the bench and perform some far more accurate tests with a newly designed spread-sheet! Can't wait!

Expect a table with all the results to be posted ASAP :D

KP

[KPARRIS-JONES]

Still nothing on the bench itself but rest assured we are actually working on this one. Today we both fabricated the Mock ITB's to give more accurate flow bench results.

I cut out the cone thrustrums from 1.0mm Sheet Steel and hammered them nice and flat before sticking this nice jig into the vice:

I then hammered in the cone shapes carefully to make the Shaft, TB and Bell-Mouth, which Owain then tacked and welded together.

Since then I whacked a bit of paint on there to neaten it up, but luckily I have kept the Templates so hopefully I can upload a PDF for download. Basically this means you have all the right size stuff to print, cut and then make yourself, enabling you to make some nice mock ITB's for testing. ;)

KP

[PaulinhoT]

Now that will sound sweet as, very clever idea enjoy reading this a lot.

[KPARRIS-JONES]

Thanks dude, I know it's quite a slow Thread, but it really does take a certain mind to be able to enjoy reading it I am hoping that this will show others how to do a home-grown FA 4A-GE like this should they choose. Every site I find people slap up a picture and the process is forgotten!

As promised, the PDF's attached are two sheets with all the Templates we used to make the Trumpet - they are a mimic of EFI Hardware ITB's for the 4A-GE. However remember that the standard ITB's are smaller, we are having ours machined bigger!

The ISAP (Intake System Adaptor Plate) is made from 1mm thick sheet steel, whereas the rest of the assembly has been constructed from 0.8mm thick sheet steel.

There are a few things to note however. The first thing is that the "Peanut Shaped Taper" is just that, a Taper with a Cross-Sectional form of a Peanut. We kinked it in at either 65mm side and welded it to the ISAP. The Peanut Taper represents the exit from the ITB's into the Intake Port of the Cylinder Head itself. The pictures below show this shape:

What the Bell-Mouth should look like:

Remember that with the Bell-Mouth, you cut it to be 70mm long, but with a final length of about 60mm once you have formed a nice rounded edge.

And here we offered it up to the engine:

The PDF's are literally the Templates we used traced onto paper and scanned in. To compensate for my writing, I have posted the dimensions of everything here too.

ISAP:

Metal Thickness - 1mm

Width - 130mm

Height - 85mm

Diagonal Sides - 50mm

Top Hole Diameter - 12mm

Outer Holes' Diameter - 10mm

Inner Holes' Diameter - 12mm

Port Hole Height - 30mm

Port Hole Width - 65mm

Intake Port Peanut Taper:

Length (When rolled) - 34mm

ISAP Side Dimensions are the same as those of the ISAP itself, however the other end has a Circular Diameter of 45mm.

Shaft:

Length - 118mm

Mating End To Peanut Taper - 45mm

Mating End to Trumpet Taper - 50mm

The Shaft is designed to have approximately a 48mm Diameter where the Butterfly Valve is in the EFI Hardware ITB's.

Trumpet Taper:

Length - 50mm

Mating End To Shaft Diameter - 50mm

Mating End To Trumpet Diameter - 55mm

This is designed to have a slightly higher taper than the Shaft, and this characteristic should progress through to the Trumpet as well.

Trumpet:

Cut Length - 70mm

Rolled Length - 60mm Approx.

Mating End To Trumpet Taper Diameter - 55mm

The overall length is affected by the welding and forming of the metal, don't be disheartened by a difference of anything +/- 10mm of the over all length. Our worked out at approximately 270mm from the ISAP to the outer edge of the Trumpet.

If you have any questions then feel free to ask!

KP

BTP M-ITB\'s Adaptor Plate, Peanut Taper and Shaft.pdf

BTP M-ITB\'s Taper and Bell-Mouth.pdf

[KPARRIS-JONES]

Right, me and the nutcase have been back on the Flow-Bench and finally we have figures and graphs!

I even have a video of her on the bench :D

We had a MPF (Maximum Potential Flow) of 151.85cfm!! Which is in technical terms "Alottafookinair"!

However, we haven't yet worked out exactly how this ridiculously shite bench works in terms of the ranges, so we may need to retest if we have gotten it completely wrong. What is still misleading is that we are given a MPF Percentage of 105% or something like that, which of course isn't possible. However it doesn't necessarily invalidate the 151.85cfm because it isn't actually a hugely outlandish number.

If someone has some results for MPF on a similar head it'd be really helpul!

We haven't done the exhaust yet! What you can tell from the graph is that we get MPF@6.53mm Lift, and from that we will probably make a cam for 7-7.25mm Lift - however I am likely going to just fit bigger Valves so we can boost that figure even more. ;)

KP

[PaulinhoT]

All very interesting stuff, I just feel useless in not being able to help you with your figures etc...

Still looks mighty cool

[nrgizerbunny]

Looks complicated, give us a better explanation!

[KPARRIS-JONES]

Thanks Paul, nrg - I'll try to offer a decent explanation tonight The maths is silly complicated but you have a basic test flow of 10" Cubic Inches Water which you set the bench to having turned it on and warmed it up so that the upper thermometer reads 28F more than the lower thermometer.

Once you have it warmed up you switch it on and set the test pressure at the aforementioned 10" (see 3rd photo in previous post and left hand vertical gauge) and you then get your % flow reading from the diagonal gauge a little to the right.

Bung the reading into the Spreadsheet and the Temperatures of those thermometers. A lot of crazy maths takes place (which I am still learning) and the % reading is converted into an actual MPF (Maximum Potential Flow) in CFM which you can then use as a benchmark for the other cylinders but primarily for when you want to see what a difference your porting has made.

The reason why the graph tops out at 151.85cfm now matter what opening you use, is because 251.85cfm @ 6.53mm Valve Lift is the maximum the port in its current state can flow. The reason why the Valve lift is important to look at is because beyond about 7mm Lift (not 6.53 because you want to go a little over to compensate for the imperfect conditions the engine will encounter) you aren't flowing any more air at all. The rule is that when you start opening the Valve beyond the size of the curtain area it sits in, you aren't going to flow more air. There are some exceptions though but it applies here and in most engines. If we open the Valves to the full 8.7mm Lift we are just putting massive unnecessary strain on the Valve train for now extra gain; it opens us up to Valve float, spring warping, shim bounce and all sorts of engine destroying effects. So we can use as little as 6.53mm lift, reducing the engines strain and producing the same power as if we used 8.7mm lift.

I'm still learning this, I know how to use the bench and I know what I'm looking at when I see it, however the maths is still a work in progress in a few areas