ALFAGTV6.COM

[Alfaross69]

That is bloody brilliant. Thats what I call swift action.

Ok, now that you showed me the water jackets under the intake I'm convinced. That is just superb.
I'm thinking of the 155 head on the 75 TS block, that would fit I'm hoping, can't see why not?
75 TS head on old nord block is more difficult since the head studs are different length.

I did mean the relief for the injectors, there are none on the 75 TS head.
On that side shot of the engine with manifolds, is that the water pump on the front cover where the PS pump is located on the 75? Looks nice and small...

I got a dissassembled 75 TS in my garage, I'll try to snap some pics asap and post them here. big difference in the mating surface of the intake/head.

Mats,
J. Steck doesn't like to bore down into head so he has stud nuts that are longer and stepped similar to a wheel lug nut so you only enlarge diameter of hole not bore down into head to recess the nuts and they still clamp from above. Also he recommended not trying to replace the studs with longer ones, also more expensive than the nuts as I recall.

Yes, that's the water pump (but its on the wrong side?but I'm not sure about that, it may be fine still some more research) as the water exits the rear of the head where the thermostat bolts on (shown in the CD diagrams) where it would interfere with firewall of GTV and spider etc..and runs forward to the radiator on the exhaust side, the opposite of the TS75 and Nord motors another difficulty in using the the 155 engine in an older Alfa.

I suspect that the relief is not needed in the head of a TS 75 because they are farther away from head in that perpendicular manifold runner, they really optimised the 155 head with the steeper runner angle and injector closer to valve, truly SWEET!!!!!
Ross

[4sfed]

Ross,

One minor correction to your description of the FWD TS rear main seal. The FWD block (164 and 155) has been shortened so the seal sticks out . . . but it is in the same location as the Nord or 75 TS.

I've also included a section drawing of the 75 TS cylinder head and manifold . . . sorry I don't have one for the 155.

[Mats]

Welcome to the board Jim! Good to have you here.

On this section the water jackets around the intake tracts on the 75 heads is obvious.
I've been thinking maybe you guys on the board can chip in on this.

The heads from the 75 TS and the 155 TS are very different when it comes to the water jackets around the inlet. Lets say that the water is around 90 degrees centigrade when leaving the head on the inlet side, which setup would be cooler for the inside wall on the inlet tracts?
Alumium is a very cood heat conductor and my gut feeling tells me that the fact that the water jackets are all around the inlet tracts would be a good thing as it would allow the cooler water (cooler then the alu that is actually conducting heat from the combustion) to conduct heat away from the inlets and hence we would have a lower intake temp.

Is this assumption correct?

Also, looking at the sections of the 75 and the 155 head the 155 head looks like the intake tracts are somewhat strangled by the oil return from the valvetrain. Is this a major concern?

[Alfaross69]

Ross,

One minor correction to your description of the FWD TS rear main seal. The FWD block (164 and 155) has been shortened so the seal sticks out . . . but it is in the same location as the Nord or 75 TS.

I've also included a section drawing of the 75 TS cylinder head and manifold . . . sorry I don't have one for the 155.

Hi Jim,
Welcome to the board. Thanks for the correction, it doesn't surprise me at all. I got it on the fly from you many months ago and was trying to recall all those issues. The photos you have generously provided are excellent for understanding many of these issues. What will you do when more folks start slapping TS's into the GTV's and Spiders, its bound to happen as the wrinkles get ironed out
If the seal is in same location then a stock 2L flywheel and bellhousing can't bolt up because of the gap between the bellhousing and rear of engine block? Is the mating surface of the 2L Nord bellhousing a different shape from the mating surface of the 155 block? Can you verify this once again?

Mats,
Drawing shows injector just outboard of head so no relief for the injector on the head itself. Yikes! that looks like a pretty good kink in the inlet tract where the manifold bolts up to the head and it looks like the injector could be shrouded by the fact its not really in the tract itself.

Attached is photo close up showing the access plugs to water jacket. I posted a close up of stock condition of water jacket access plugs

[Mats]

Thanks Ross. That whole area surrounded with the little wall in your pics is actually a water jacket on the 75 TS engines.
The injector on the 75 squirts fuel straight at the valve so probably no shrouding effect at all, very efficient I think, but the air is a bit different with the kink in the intake. Actually it's not as bad as in that section, there is a small radius in the "mouth" of the head.

Are the cams different? Can you fit 75 cams in the 155 head? Never mind the VVT now...

[Alfaross69]

Mats ,
I dont know about the cams, make that request to "wesley 55" on the Alfa bb site,he's already tearing into the motor and the 155 head, I haven't even started yet, got too many projects right now.I think he mentioned he was getting C&B ? cams for it ?

[Maurizio]

When you order from C&B you have to mention used for a 75/164 or 155. And as far I know, do they work with the exhaust timing gear also mounted on the intake cam and ditch the vvt.
See http://www.colombo-bariani.com/catalogo.php?lang=eng

[Mats]

Since they are listed like that they are probably very similar, maybe only the ends that are different since they have distributors in different locations (or not at all as on the 155) maybe the VVT drive is different too, sure looks like it but you never know. Can't imagine that they (C&B) chose to retain the possibility of a VVT on the Corsa cams.

[Maurizio]

A few days ago I had the origional exhaust cam of my 75 in my hands and the cam has the provision for the distributor on both ends.
On the AR parts cd the cams for 75 and 155 have different numbers.

[Mats]

Snapped some pics just now...

Intake side with water jackets.


The rear of the intake cam. slot for grinding process?


Front ends


Edit: updated links 7/9

[4sfed]

I'll try to clarify a couple questions of compatibility between the 75, 164 and 155 TS heads . . . in no particular order.

The 75 and 164 heads are interchangeable. The slot on the rear of the exhaust cam is used to drive a second distributor on a 164. The 164 timing cover is very different and has no distributor.

As far as I can tell, the shape of the ports in the 155 head are almost the same as the 75. The raised intake manifold requires a different angle on the injectors and the relief in the head.

Overall, the FWD engine is much shorter. The rear of the block is shortened and the timing cover is shortened. A 105 bellhousing and flywheel will not work with a 164 or 155 block without an adapter. The Bonneville engine (155 block) needed a stronger transmission and a 1/4 inch thick steel scattershield to meet safety rules, so I needed to make a custom bellhousing anyway. Here is the the bellhousing/scattershield. BTW, the requirement for 360° coverage is to keep parts off the course . . . protecting the next competitor from parts the course marshals may have missed. The rear-mounted starter makes room for a larger intercooler.

75 and Nord timing covers will bolt up to a 155 or 164 block, but the pan rail at the back of the block is different and will not allow a bat-wing or Alfetta pan to bolt up. Attached is a photo from the rear of a 155 showing the oil seal detail.

The base circle of the intake cam is larger than the exhaust cam on TS engines. They are not directly interchangeable, but an exhaust cam can be used as a core for a welded-up cam.

If the distributor drives are removed, 75 TS cams can be used in a 155 head. Some 155's do not have VVT's . . . don't ask me which models . . . I have one of each.

[Mats]

Interesting facts there Jim. Those scattershield/bellhousing pics are pure porn, some really nice welding going on there... But do you really need that enormous starter engine? Weight must be an issue even at Bonneville?

So what you're saying is that the heads and cams are interchangeable as long as you do not care about distributors and VVT?
So about the only reason for using the 155 head would be the clean look (Assuming the intake water jackets doesn't matter from a performance point of view, although they probably do.)?
Surely one could make a proper intake manifold to fit the 75/164 head even though from looking at it the floor of the mouth in the head needs to be lifted just a liittle bit.

[Maurizio]

Hmmm, pure porn:

155 stw

[Mats]

Eh, don't start mixing in the Lancia 16v engine Maurizio...
BTW, note how they changed the flow direction in the head. RHS is hot side on those ones. gear driven cams are quite nice too.

The 8v TS F3 engines are similar but are based on the 75 TS engine. There are usually some for sale if you know where to look.

[4sfed]

Mats,

The starter is from a VW Rabbit . . . about the same weight as a 1600 starter. Trick was finding a reverse rotation starter with the same pinion. Weight is not the big issue at Bonneville. We gained only 1-2 mph per mile in the last two miles. Aero and horsepower are most important.

Yes, I think you can get the same performance from either head. I like the look of the 155, and hate trying to seal the cam cover on the 75/164. Just wait until you want to check valve lash or experiment with cam timing.

The 155 head also matches the Spider/GTV timing cover.