Narrow-Width T4

[cal 67]

My next build will be a Type 4 engine for one of my 67 hardtop Bugs. I have this 1.7 core here, and was thinking to build a 66x105 maximum effort engine. I don't mind modifying cooling tins, sealing the compartment, or getting a header made. My plans are:

Six-studded case

66 stock stroke - rifle drilled, non c/w, maybe Mazda journal so I can run a 20mm piston pin

Either Mazda 5.0" rods or SCAT T4 H-beams with 22mm pins

Undecided on cam, but 1.5 ratio Weiss rockers and 7500 peak powerband

JE custom FSR pistons with the highest compression height possible (21-23mm)

T1 valvetrain, aluminum dual tapers, TI retainers, light springs, and Knuf lifters

Ridiculous heads. Probably dual plug.

Tri-Y probably

Anyways, it's gonna be incredibly narrow. Possibly 1" or more per side. I know some things are going to hit, like the barrel big ends on the oil cooler in/out, and I'm sure the pushrod tubes will be an issue.

What else am I missing?

[patto]

Any progress on this build ? would be an interesting combo for sure!

[cal 67]

Any progress on this build ? would be an interesting combo for sure!

A bit. I’m building a 96x82 Type 1 at the moment, then I have a customer’s T4 engine up next. He’s from Florida and I need to ship to him when ready. So far it’s a 82.2 full circle with 5.325” rods and 105mm bore. Building it to drag in one of the lighter model Split Buses. That one should be pretty narrow too because the pistons will be custom with a 22.5mm compression height. The heads are out right now at a newer head porter’s shop. He has been making big flow numbers through small valves, so I reached out to him. If the heads turn out well I’ll send my set to him as well.

So far here’s my idea for my T4 combo:

1.7 case, six-studded - I might add piston squirters and/or valve squirters

66 stock stroke, non counterweighted, rifle drilled rod throws, Chevy jrl, done by DPR

AA flywheel, modified with bushings to take up the slop, ARP bolts, Swiss cheesed at DPR (already purchased)

4.78” aluminum rods, Chevy Jrl, 22mm pins, very short - 1.8 ratio (already purchased)

Dry-sumped - not sure on specifics because I don’t know enough about it

JE custom FSR pistons - I need to get them very light, 22mm compression heights, .100” minimum crown thickness near valve reliefs and about .150” everywhere else, 1.2x1.5x2.8 ring packs, .120” wall very short pins, coated skirts and crows, pin oilers

Not sure on barrels yet. It’d be a shame to cut down Deutzes to nothing. But I might be able to get by with just using two liners to make four barrels...

AA 914 bare heads, dual plug, welded reshaped chambers, whatever valve sizes the head guy comes up with based on his flow results. The whole build’s output is reliant on his results. He said he’d port the exhaust first with the stub pipes, then port to ~75% of that for the intake. Then he can decide on valve sizes. He tends to use the smallest valve possible. I’ma try to find a suitable 7mm valve/retainer/light pressure spring combo for them.

Hopefully we can develop heads that can support 7500-8000rpm. I’ll choose the cam after that.

Holger Lashchinger aluminum 1.4 ratio rockers, custom-made pinned solid spacers (already purchased)

CB/Manton dual taper aluminum pushrods, 40 grams (already purchased)

Kummetat 41 gram lifters with bronze bushings, 356-style with 28mm heads (already purchased) - sending to SLR for modification

Custom-made intake runners with throttle bodies - angled outward so I can see the valves when I stare down the barrels

4-2-1 SS custom made header system - the engine will be narrow enough to get the primary length ideal. The 4 and 1 will join and the 2 and 3 will join, so they’ll merge near the drain plate.

Bought a JayCee 5 1/2” pulley with his new T4 hub

Compression will probably be set around 12.0:1, dependent on theoretical psi. Needs to run on 91 U.S. pump fuel, aiming for over 250 HP at 7500+ rpm, going in a 67 Bug vintage rally-inspired street car that sees about 12 fun miles a day. I could care less about longevity or mileage. I’ll tune it well and do what I’ve always wanted to do.

I’d upload pics, but it’s a PITA here.

[patto]

Sounds awesome!
Im currently building up a 66mmx98mm 2 litre track car for racing!
In the same position as you with the cam and I have attached my latest flow numbers from 44mm x 36mm valve and standard chamber! could probably squeeze out some more with chamber work but im keen to get on the track.

IMG_6905.jpg

[wreck]

I'm running a scat C55 approx 265 @ .050 and .530 lift on the intake and .500 on the exhaust because of the standard type4 rockers . I've a Web 227 that I'd like to try but don't have the compression(10.5) for it and wonder if the higher revs will be pointless because according to Pipemax and other valve calculators my intake valves start to choke at 6300 .(2.6lt with custom 47mm 7mm stem valves) .

Patto very interesting that Tony Knight is doing a set of 914 heads , I read forums on the work he did on the M20 BMW engine and the Datsun 2lt . Please keep us informed how it performs .
If your interested in performance NA engines both these links are worth reading .

http://www.performanceforums.com/forums ... K-goodness

http://performanceforums.com/forums/sho ... atsun-head

[cal 67]

Sounds awesome!
Im currently building up a 66mmx98mm 2 litre track car for racing!
In the same position as you with the cam and I have attached my latest flow numbers from 44mm x 36mm valve and standard chamber! could probably squeeze out some more with chamber work but im keen to get on the track.

IMG_6905.jpg

Looks like you don't need to lift over .550". Those are solid numbers through those valves! Tested at 25"?

[patto]

Looks like you don't need to lift over .550". Those are solid numbers through those valves! Tested at 25"?
[/quote]

tested @28" those numbers should get us over the 200 horse power range if every thing else goes well.

[patto]

I'm running a scat C55 approx 265 @ .050 and .530 lift on the intake and .500 on the exhaust because of the standard type4 rockers . I've a Web 227 that I'd like to try but don't have the compression(10.5) for it and wonder if the higher revs will be pointless because according to Pipemax and other valve calculators my intake valves start to choke at 6300 .(2.6lt with custom 47mm 7mm stem valves) .

Patto very interesting that Tony Knight is doing a set of 914 heads , I read forums on the work he did on the M20 BMW engine and the Datsun 2lt . Please keep us informed how it performs .
If your interested in performance NA engines both these links are worth reading .

http://www.performanceforums.com/forums ... K-goodness

http://performanceforums.com/forums/sho ... atsun-head

Thanks for that Wreck! Yeah Tony is a pretty damn impressive, first set of VW heads he has done and already got better numbers then others have posted and with smallish valves and port velocity is crazy so they should pull from down low all they way past 8K
See how we go with this build then we will look at new chamber shapes etc for the next one.

[wreck]

Thanks Patto , maybe you could start a thread on your build . Great to see some very high performance type 4's being built .

[patto]

Thanks Patto , maybe you could start a thread on your build . Great to see some very high performance type 4's being built .

Will do for sure when I get a few more parts and have the cam sorted etc

[Wally]

So far here’s my idea for my T4 combo:

1.7 case, six-studded - I might add piston squirters and/or valve squirters

66 stock stroke, non counterweighted, rifle drilled rod throws, Chevy jrl, done by DPR

AA flywheel, modified with bushings to take up the slop, ARP bolts, Swiss cheesed at DPR (already purchased)

4.78” aluminum rods, Chevy Jrl, 22mm pins, very short - 1.8 ratio (already purchased)

Dry-sumped - not sure on specifics because I don’t know enough about it

JE custom FSR pistons - I need to get them very light, 22mm compression heights, .100” minimum crown thickness near valve reliefs and about .150” everywhere else, 1.2x1.5x2.8 ring packs, .120” wall very short pins, coated skirts and crows, pin oilers

Not sure on barrels yet. It’d be a shame to cut down Deutzes to nothing. But I might be able to get by with just using two liners to make four barrels...

AA 914 bare heads, dual plug, welded reshaped chambers, whatever valve sizes the head guy comes up with based on his flow results. The whole build’s output is reliant on his results. He said he’d port the exhaust first with the stub pipes, then port to ~75% of that for the intake. Then he can decide on valve sizes. He tends to use the smallest valve possible. I’ma try to find a suitable 7mm valve/retainer/light pressure spring combo for them.

Hopefully we can develop heads that can support 7500-8000rpm. I’ll choose the cam after that.

Holger Lashchinger aluminum 1.4 ratio rockers, custom-made pinned solid spacers (already purchased)

CB/Manton dual taper aluminum pushrods, 40 grams (already purchased)

Kummetat 41 gram lifters with bronze bushings, 356-style with 28mm heads (already purchased) - sending to SLR for modification

Custom-made intake runners with throttle bodies - angled outward so I can see the valves when I stare down the barrels

4-2-1 SS custom made header system - the engine will be narrow enough to get the primary length ideal. The 4 and 1 will join and the 2 and 3 will join, so they’ll merge near the drain plate.

Bought a JayCee 5 1/2” pulley with his new T4 hub

Compression will probably be set around 12.0:1, dependent on theoretical psi. Needs to run on 91 U.S. pump fuel, aiming for over 250 HP at 7500+ rpm, going in a 67 Bug vintage rally-inspired street car that sees about 12 fun miles a day. I could care less about longevity or mileage. I’ll tune it well and do what I’ve always wanted to do.

I’d upload pics, but it’s a PITA here.

I would do it a little differently based on past and recent experiences:
You don;t really need 6-stud or piston squirters.
You deffo don;t need alu rods. Alu rods arewere shock absorbers for funny car nitro engines, other then that, better buy a set of light weight Pauters. Sleeps better too.

The saved money is better spend on the heads, i.e. stepping up to billet heads and getting into much better flow numbers. You need the latter more then anything for great power.
With the billet heads, you then have type 1 exhaust pattern and you can order a Wasp and get max out of it. That combo (billet heads and Wasp) with your intende CR, WILL give you > 100hp/ltr, almost guarenteed.

Just my 0.02
Walter

[cal 67]

Hey Wally. Idk if you’re familiar with Torben Alstrup, but he recommends 6-studding whenever going over 98mm for leakage purposes. With a 105mm bore and such a thin sealing area I could see how the head would warp between the studs. For the peace-of-mind alone I’ll be doing that. I agree with the Pauters. It’s just what I have, and I want a very light rotating/reciprocating assembly that’ll rev very quickly. Longevity isn’t a real concern for me. I’ll do a teardown now and then to check things. Also, the conn rods will be less stressed because of the weights of the connecting parts and the rod/stroke ratio. About the heads, I have a set with my proposed head guy now. Depending on the results I’ll either go with him or go another direction. He’s really good though, and I don’t doubt his ability to extract big cfm from the stock 914 castings. Time will tell... As for the downward ports, they are really appealing to me because a proper tri-y isn’t possible with side-exiting ports. The primaries would be a little too long, and the goal is to get my exhaust and intake within the same operating window.

[cal 67]

Oh, btw I got a AA 200mm flywheel last week and I’m ordering suitable bushing material to machine. The holes are 13.09mm as-is. I found some material to slip-in and hug the bolt perimeters for a tighter fit. No drag racing hammer drops, but it was just too sloppy for my tastes.

[Wally]

Hey Wally. Idk if you’re familiar with Torben Alstrup, but he recommends 6-studding whenever going over 98mm for leakage purposes. With a 105mm bore and such a thin sealing area I could see how the head would warp between the studs..

Yes, I know Torben from his postings, not in person though and agree he gives good advise.
However, we do not disagree as my proposed combo used billet heads! Billet heads don't warp. Its a whole different ball-game. Thats why I said 6-studding isn't neccesary: only when using the so much stronger heads. Cast heads cannot be compared to the billet ones. Its a very different alu and extremely strong.

I do agree on the bottom exit of type 4 heads: that is an advantage in my book as well, its only that the Wasp header makes such awesome power, that you cannot make that yourself..

[Wally]

Oh, btw I got a AA 200mm flywheel last week ...... The holes are 13.09mm as-is.

That is actually not too bad! Mine was 13,5mm! The shanked 12.9 bolts from Ahnendorp or other german/danish sources might just be a direct fit then! I think AA revised their product, again in a good way! Looks like the listen to us