2,4 T4 201,1Hp wants more!

Post by **Piledriver** » Fri Feb 13, 2004 1:36 pm

I had an idea that might help the sealing issue I posted to the wasser forum, an edited verion follows, it applies more to T4s anyway.

It also sort of relatd to possibly allowing more stroke on "short" Porsche jugs used in a wasser. See the thread.

******
(snip)
...following is a half baked idea. This may be stupid... But I've seen in in cut aways of aircraft engines... It also brings to mind the 911 jugs I saw here... almost no cylinder projection above the top fin...

The #1 issue with big bore jugs on a T4 (103-105) is the heads dont have enough meat to stay flat at the sealing surface.

Figure out where the top ring stops.
Cut the jug ~1mm (.040") up from there. This will be the new sealing surface. This is (usually) ~5mm down.
Step cut the head for the 103s AWAY from the std sealing surface by the same amount you cut off. The center std part gets bored for the PISTON crown with a tad of clearance... In other words, the head becomes the top of the bore that does not see the rings.

The net result is you end up with ~4-5mm of extra aluminum in the head in the direction that provides sealing surface stiffness, and ~5mm less "uncooled" cylinder in the head, the sealing surface is closer to the top fin etc. The "effective" combustion chamber is all in the head.(including the first 5mm of bore--end result would be jut about flush with the stock casting/machined area surface)

Might be effective on T1s in a blown app for better cooling/more rigitity.

(from 85.5 openings>94s)
...

I elaborated later, the thread is:
http://shoptalkforums.com/viewtopic.php ... 6&start=30

And only a vocal few have an issue with "Jakeness"

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Fri Feb 13, 2004 2:07 pm

The sealing issue can be taken care of with a Special Inconel filled O-r ing that we are working with now on 102 Nickies...

Nickies would probably solve the issue without anything else to aid them. I don't know if the Inconel o ring is compatible with Cast Iron cylinders

cnavarro · Post by **cnavarro** » Fri Feb 13, 2004 3:13 pm

The inconel gas filled o-ring option for the 102 Nickies are made for us by Garlock Heloflex. Top notch bad ass technology. Can take up fifteen to eighteen thousands of lift at the cylinder and maintain seal, under boost.

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Fri Feb 13, 2004 3:20 pm

Yep....

Wesayso · Post by **Wesayso** » Fri Feb 13, 2004 5:23 pm

Piledriver wrote:I had an idea that might help the sealing issue I posted to the wasser forum, an edited verion follows, it applies more to T4s anyway.

It also sort of relatd to possibly allowing more stroke on "short" Porsche jugs used in a wasser. See the thread.

******
(snip)
...following is a half baked idea. This may be stupid... But I've seen in in cut aways of aircraft engines... It also brings to mind the 911 jugs I saw here... almost no cylinder projection above the top fin...

The #1 issue with big bore jugs on a T4 (103-105) is the heads dont have enough meat to stay flat at the sealing surface.

Figure out where the top ring stops.
Cut the jug ~1mm (.040") up from there. This will be the new sealing surface. This is (usually) ~5mm down.
Step cut the head for the 103s AWAY from the std sealing surface by the same amount you cut off. The center std part gets bored for the PISTON crown with a tad of clearance... In other words, the head becomes the top of the bore that does not see the rings.

The net result is you end up with ~4-5mm of extra aluminum in the head in the direction that provides sealing surface stiffness, and ~5mm less "uncooled" cylinder in the head, the sealing surface is closer to the top fin etc. The "effective" combustion chamber is all in the head.(including the first 5mm of bore--end result would be jut about flush with the stock casting/machined area surface)

Might be effective on T1s in a blown app for better cooling/more rigitity.

(from 85.5 openings>94s)
...

I elaborated later, the thread is:
http://shoptalkforums.com/viewtopic.php ... 6&start=30

And only a vocal few have an issue with "Jakeness"

I have thought about this too, but I'm not quite sure it would work...
I'm on the same track as Wally with the 964 Porsche 100mm cylinders on a type IV but with 1.7 "Q" heads... (wally has the 2.0 heads)
Since I'm going to be using a 76.4mm stroke I'll need some spacers but not much. I could do a stepped cut in the head like you're talking about, use part of the head for cylinderspace above the rings (with the proper clearance) and use more of the original cylinders in the top space as a mating for the rings...

Would this be a good idea to persue or would it have drawbacks?

sort of like this:

Bobby74 · Post by **Bobby74** » Fri Feb 13, 2004 6:45 pm

Wheeew! This thread really took off! Good info guys..

[email protected] wrote:So Bobby,

When you are talking about getting rid of the IDA type throttle bodys, are you suggesting putting a plenum/runner system in with say a throttle body from something like a GM3800 on the plenum? I am working on something like this for an Electromotive Tec2 on my 2.3L with a FAT shroud. Any suggestions you guys have would be appreciated.

Thanks,

Randy

Yes, I was tip-toeing around a plenum/runner system. I feel they are the best compromise between torque and top end power. Not to mention if you get everything just right the internal supercharging effect can give you a little boost at certain RPM ranges (depending on plenum volume, shape, and runner length and diameter, many factors to concider).

Ok let the games begin!

Post by **Piledriver** » Fri Feb 13, 2004 7:19 pm

Exactly, and the o-ring and the step cut both have advantages, and are not mutually exclusive---one could do BOTH.

It was discussed and elaborated on in the wasser thread.

Thanks for doing a picture!

Bobby74 · Post by **Bobby74** » Sat Feb 14, 2004 1:42 am

This is a half-assed approach but it would work... cut the cylinder at an L-step of about 0.020" and have the head be resting on 2 "steps" of the cylinder instead of just one flat spot. This gives you a little room for flex and hopefuly and carbon that built up could keep it sealed enough to prevent head melting... Like I said, half-assed.
-Bobby

P.S.... what if you made a T6 or Stronger plate and milled the head down? The plate would go to the underside of the head with a few smaller cap screws (recessed into the plate). You could stiffen the head up so it won't flex.. I believe the stock alloy is 356A, and its about as weak as you can get.. Using a stronger plate would give the top end the rigidity it would need to keep from flexing.

This might cause problems with expansion and contraction and heat soaking..

cnavarro · Post by **cnavarro** » Sat Feb 14, 2004 5:26 am

One little detail....you can't use an o-ring on a 103, there just isn't enough meat on the sealing surface, that's one reason we only offer it on a 102. You could always weld the cylinder and head together like Porsche did

Maybe I should start offering that service!

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

Post by **Piledriver** » Sat Feb 14, 2004 8:27 am

...Weld...

Yes, but that would only work on Nickies.
(Iron doesn't weld to aluminum...Although I have seen folks try;-)

For an "Extreme" application, it might be useful, like an aircraft.
Or someone wanting to run 50 LBS of boost.

Like I said, I was just curious if the added material idea was possibly viable.

raygreenwood · Post by **raygreenwood** » Sat Feb 14, 2004 2:28 pm

I knew he wasn't insane. My brother is working on my heads right now. He suggested the inconel ring a few monthes ago. I may let him work it in, if I can get the right size. Ray

Post by **Piledriver** » Fri Dec 03, 2004 8:07 pm

Where do you get those inconel O-rings, and do you have dimentions for the o-ring grooves?

Planning a 101.6 bore, Deutz jugs, found a source, cheap.

Wally · Post by **Wally** » Sat Dec 04, 2004 2:09 am

Piledriver wrote: Planning a 101.6 bore, Deutz jugs, found a source, cheap.

Glad to hear!

But I don't think that the inconel ring or any such idea is designed to be used with steel jugs and an alu head. I'm sure you get the picture.

Walter

cnavarro · Post by **cnavarro** » Sat Dec 04, 2004 2:54 pm

I now can put sealing rings made for the 3.6 911 that are dirt cheap on to the 100mm type 4 nickies. The rings run about $2/ea, vs. the $75-100/ea of the inconel gas filled

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

Post by **Piledriver** » Sat Dec 04, 2004 7:23 pm

I thought those inconel rings were first tried for alu head/iron blocks... I'll have to goodle for history, but an o-ring shouldn't CARE what materials it's used against.

The fact that it's flexible is sort of the point...

What are the 911 ones made of? Copper?