2.9l street engine build

[Arnoud]

Oliver Knuf now works for Kummetat if I understood correctly?

I believe he is now the Head Honcho down in Gelsenkirchen.

[Eddie010]

Oliver Knuf now works for Kummetat if I understood correctly?

I really like the 4-2-1 style exhaust and I even think I seen it at Engine Plus back in the days when they sold their T1-T4 billet heads for type 4 still. From my understanding the 4-2-1 lay-out will probably not have that very common dip around 3500 Rpm that most 4-1 dyno sheets with bigger cams have.
From both I have now gotten inspiration again, so I'll make exhaust in that idea as well, but with a twist I'll open a topic here for it

I really like the stepped headers they make like the JPM Wasp system, keeps the exhaust gasses in speed in the headers..
But they only make those for the type 1 world.

The 4-2-1 above here (MegaRookie) is also going from small tubing to big tubing… so I think will have the same exhaust speed advantage...
Looks nice

Edgar

[MegaRookie]

Thanks Richard for the info on the 5th and 6th stud! Looks like a very nice solution with the spacer. Due to the very long cylinders and stroker pistons I don't need a big spacer (only 0,2mm/approx. 0.01") but Ill start with the original 4 studs.

Ps. I use 5.7" rods.

Too bad you had to put your project on hold! Are you going to start it up again?

Thanks Walter, I am also very curious what kind of twist you are giving it!

And Edgar, yes I am using different sizes of tubing, it starts small due to the limited exhaust port size and clearance to the pushrod tubes, then the primaries go to 50,8mm (2"). At the first collector the two 2" pipes go to 1 55mm (approx. 2.17") and at the second collector they go to 63,5mm (2.5").

I'd rather use 57mm instead of the 55mm amd 48mm instead of the 50,8mm, but because I allready had the 55mm, i thought, why don't try this first. At my 2l engine I also had an exhaust which was a bit too big (42mm) but never had problems with it.

The case is finished so far, and was cleaned at my work in the industrial cleaner yesterday. I will double check the oil bores with a special 15mm bore brush, to be sure they are really clean.

And the guy who does the machining for me called that the balancing was finished and that the machining is also done. He was only waiting for the valve locks so he can finish the heads.

So there will be another update soon.

I wish you all some great Easter days and all the best in this crazy world we are living at the moment!

Mark

[Type 4 Unleashed]

Should you decide to go the 5th & 6th studs, you could still go a stud mounting plate just with holes large enough for the cyl's to slide inside instead of on top, that would keep from having to split the case for welding the stud attachment blocks, maybe even requiring a line bore afterwards ? There looks like enough room on the long cyl's for a plate.

I plan to eventually get back to my Type 4 project, but I have currently gone to the dark side and I'm working on a 7.7 ltr America Muscle project.

[twodollardoug]

But wouldn't you have to lengthen the rods to make up the difference for the thickness of the plate?

[GARRICK.CLARK1]

You would shorten the cylinders.

[Type 4 Unleashed]

In Mark's case, he wouldn't have to go longer rods, or shorten the cyl's there is no need. The only purpose of the plate would only be to have a place to anchor the additional studs, it would not be a spacer plate, it is now only a stud plate.

Let me hold every ones hand and walk you thru my suggestion, the I.D. cyl holes in the stud plate are made larger then the cyl's seating surface and the cyl base would now slide thru the plate and the base of the cyl would seal against the case, the cyl's base is not sealing against the plate they are going thru the plate and sealing against the case, they are now not a spacer plate but only a stud plate.

[MegaRookie]

Thanks Richard,

I have also been thinking about this. But due to the limited space between the cylinders I would make a separate top and bottom stud holder plate.

Today I finished cleaning the case and I got a call from the machining guy that the heads and crank will be shipped tomorrow. When the heads arrive here I will make a drawing of the stud holders and see how they align to the heads.

One question. What studs do you use for the case and the 5th and 6th? For now I planned to use the original for the case and have extended ones for the cylinders from AA with arp nuts. Might some cromoly t1 studs or original t4 be used for the cylinders?

Thanks!

Mark

[Type 4 Unleashed]

You won't need to make seperate plates. A single plate will work fine. The plates would need to be at least an inch thick, to be able to support the studs.

Actually I would'nt mix the studs, I'd mount all 6 tuds per cyl in the plate and the studs would all be the same material and have equal expansion rates. Lengths will have to be figured out, I would start with Scat Type 1 8 mm studs, which are a good quality stud, and the studs used on the split ports.

[MegaRookie]

Thanks for your advise Richard! We'll see with what kind of solution I will end up with this engine.

For now a small update. The flanges for the gearbox arrived after 3 months, so I started with the conversion from 90mm cv to 100mm.

I also got the heads and balanced crank back. Earlier this week I cleaned the parts and brought the rods to the same weight within 0.3 gram and yesterday I took some time to assemble the rods and cam gear. Unfortunately the racer spacer I had in stock for some years did not fit at all. Even after 15 minutes in the oven it didnt expand so much that it would fit, so it ended in the trash can after cooling down and I ordered a new one.

Below 2 pictures of the crank can be found, and at the bottom one the clearance for the cam can be seen.





Next week I hope to have some time to clean the parts so I have everything ready to close the case.

Mark

[MegaRookie]

Good morning guys,

Small update again. Yesterday I had most of the parts so far that I could do a final check before assembly.

I started with the oil pump. Unfortunately I had to grind the threads a bit, but now it clears the bolts on the cam for more than 1mm.



After that, I checked the clearance from rod to cam, just to be sure that it clears enough now the rod bolts are set to the correct torque. And with the rod of the 4th cylinder I have just 1mm clearance:





The second cylinder also needed to be rechecked, but thats for another day. unfortunately I saw at assembly of the crank in the case that one of the Silverlite bearings I used needs to be deburred Never seen that on a bearing before, even not the real cheap ones. So just to be sure I will remove the gears on the crank again, just the be sure that the one on the crank is also free from these small pieces. (I already cleaned that bearing but I cant remember that I had attention for those small particles that were still half fixed)

The last thing I did was starting to fit the small oil sump. Somewhere I read about tw different lengths of pickup tubes. Can you guys tell me if I have the correct length here? (I am not sure that this tube comes from this case, so just to be sure.



This length means that the O-ring sticks through beyond the oil passage, is that correct?



Thanks to you all, and I wish you already a very nice weekend!

Mark

[Richie]

Hi,

You need a short oilpickup tube because you have a later crankcase there.
The long one you have there is for the earlier cases without the oilreturnchannel (better word? )

Cheers,
Richard

[Type 4 Unleashed]

Why are you going to use a stock pump ?

[MegaRookie]

Hi,

You need a short oilpickup tube because you have a later crankcase there.
The long one you have there is for the earlier cases without the oilreturnchannel (better word? )

Cheers,
Richard

Thanks for your reply Richard, then Ill have to search for a short one.. (happy that I did not weld the pickup extender to it

Why are you going a used stock pump ?

At my previous engine I also used a stock pump. I log the pressure with the MS2 and never had any problems with it (also at 6500+ rpm). Do you advise another size? And why? From one view I would say that a bigger pump is better, but from the other side I would say that you would heat up the engine more, because the flow that not can be used will be turn into pressure and pressure more than the spring will hold will be flown back to the case immediately (and will normally) produce heat.

Thanks!

Mark

[wreck]

I just pulled my 2.6 (78x103) down it's down 22000km , apart from the worn valve guides , the only other wear was on the silver line rod bearings , only on the piston side . the main bearings are fine and I'll reuse . I've heard a few people won't use the silver line rod bearings . I'm going to try KS rod bearings .

I thought about using a stock oil pump , the only one I have had good internals but the body was broken by someone levering it out of an engine . still working on the best solution on type 1 oil pump fitment .