SCCA T4 Build thread

[bmacfrs]

Wow. One thing always leads to more doesn't it. Hope all the assembly goes well.
Thinking about using some wrap as well since I trashed the right side of my hot lava last season. You know what 3M code you have there?

as always, thanks for sharing.

[rice_classic]

Originally Posted by bmacfrs

Wow. One thing always leads to more doesn't it. Hope all the assembly goes well.
Thinking about using some wrap as well since I trashed the right side of my hot lava last season. You know what 3M code you have there?

as always, thanks for sharing.

3M 1080 G364 - that's the Droid you're looking for.




More UPDATE.
Finally tore the heads off. Couple things of note - The cylinder look incredible. This was a street car then ran hard for 3 full race seasons and yet everything looks great.

Except for the RTV - holy balls there's WAY too much excess RTV everywhere and I suspect that the overuse of this stuff causes failure in some engines where it comes off.




Left over Sealant on the end of the cam.





Cylinder:




While I had the pulleys off I figured I'd pop the seals and inject some new Amsoil Dominator bearing grease into them.




Making a mess in the garage...

All boxed up and ready to go machine shop

[Autoxer62]

I know several people who curse at RTV, those photos are why. More is definitely not better, I'm disappointed at seeing that on a factory built engine.

[CrowsFeast]

Originally Posted by rice_classic

Cylinder:

Am I mistaken in thinking that it looks like there wasn't a good seal between those 2 cylinders? Also surprised the hone lines are so clear!

[Capt Spaulding]

Originally Posted by CrowsFeast

Am I mistaken in thinking that it looks like there wasn't a good seal between those 2 cylinders? Also surprised the hone lines are so clear!

1. Looks in amazing shape for the use it's seen. Humfrz might say it's "clean Livin" I couldn't say.

2. They used enough RTV for 3 engines.

3. The crosshatch being so clear could be due to piston speed differences. At both ends of the stroke the pistons slow way down. Eventually to 0 fps

[rice_classic]

Over the life of the car, before and during being a race car, I've played with different additives like TCW3, octane boosters etc. Some of the discoloration is a function of that. Cross hatch looks impeccable in every cylinder throughout the stroke - I am very impressed and this supports my decision regarding oil choices, OCIs and driving. The story can change though once I look at the bearings!

No issues with the headgasket, what you're seeing is the mess that occurs when you pull up the head - the remaining coolant sort of splashes on everything. During the life of this engine, the coolant level never moved.

As for RTV - this engine had the valve spring recall performed so RTV excess on the timing cover, valve cover and cam cradle are a result of the toyota dealership tech using an excessive amount of RTV that is Spec'd by the instructions they use for the recall.

After I get the heads and valve train out of the garage, I'm going to open up both the old and new blocks. What I'm looking for is the ring end gap. I want to know what it is on the old engine and make sure on the new engine it's minimum spec, even if that means I need to buy new rings and file them myself.

T4 rules are restrictive - I basically can't do ANYTHING that falls outside of the specifications in the factory service manual. Even if I go to .020 overbore pistons I would have to add weight to the car. Therefore all of of this work is so I can (hopefully) gain 2-5whp with a fresh engine. I'm going to run minimum ring gap, tight valve lash, maximum material off the head (up to .004") and clean up the valve seats. I'm also going to get my Flywheel resurfaced and balanced with a new pressure plate. Considering how this engine looked - I'm accepting a possibility that I gain nothing from all this on the dyno... But that's racing.

[Capt Spaulding]

Looing forward to your results. BTW - what were your choices as to OCI, oil choice/cooler?

[rice_classic]

Originally Posted by Capt Spaulding

Looing forward to your results. BTW - what were your choices as to OCI, oil choice/cooler?

When street car - 0w-30 usually amsoil signature because I went 7-8k mile changes but I would change the filter at half the interval (4k).

When race car - Jackson oil cooler and I use a variety of oils depending on ambient. Usually a 5w-30 or 10w-30 Valvoline Full Syn High mileage or Mobil 1 0w-40 euro. (all available at Walmart). It gets changed more often on what is a stock engine, so I don't see a need or reason for the expensive stuff. At the runoffs I used 0w-20 because of the low temp at a championship race so I want to reduce resistance on the oil pump.

From a use-case: I never let myself rev the engine high while the oil is cool. Long standing habit I learned from my father that a vehicle should never be driving hard until it is properly warm. I suspect some of the oiling issues on these engines are: running too hard on cold oil as well as running too thin oil too hot. On pregrid I can see my oil temp on my Solo DL2 so I try to make sure it's above 160F always before I head out on track and then I'll do a lap before I let it sing, unless there's a reason I need to be at full boogie leaving pre-grid (which is rare).

SCCA just updated T4 to allow baffled oil pans so that's also a step in the right direction as well.

[Autoxer62]

Based on what I've read on the forum, I'm pretty sold on the idea of replacing the pickup and baffling the oil pan.

[strat61caster]

Curious if you'll do any injector test/cleaning?
Am I right to presume you'll do a post rebuild Dyno to confirm your comp weight for next year?

[rice_classic]

Originally Posted by Autoxer62

Based on what I've read on the forum, I'm pretty sold on the idea of replacing the pickup and baffling the oil pan.

Baffle is now legal, changing the pickup is not legal so can't do that. But nothing I've seen so far suggests I've ever had an oiling issue.

Originally Posted by strat61caster

Curious if you'll do any injector test/cleaning?
Am I right to presume you'll do a post rebuild Dyno to confirm your comp weight for next year?

100% I'll probably drop them off at Dr. Injector this week. Only doing the DI's this time since they do most of the work. I don't race in a power|weight class so finding more power is all benefit. T4 is a spec line class and weight is only adjusted for Balance of Performance reasons. I have lobbied the competition rule board to take some weight off the car so we'll see, but I'm not placing any bets on that happening.

[Capt Spaulding]

Very cool. I enjoy reading about you guys' experiences. Your approach to oil temp closely resembles mine (not really surprising since your dad probably hails from my generation). It was on air cooled motorcycles with no oil temp gauge but I tried to make sure the oil cooler was too hot to touch with a bare hand as we finished the sighting lap.

[rice_classic]

Injectors:

After 1 season, my injectors were in need of service. Dr. Injector said that I should run a decent injector cleaner every few race weekends and the service interval for them will be longer.




Pistons and Bearings
So now that I know the cylinders look amazing, how about the side skirts and rod bearings?

Some minor scoring on the bearings, but they look really good considering the 5 years of street miles and 3 seasons of racing and their wear is pretty identical between between them. I guess it's that kick ass Valvoline Syn High Mileage oil I swear by!






The heaviest side skirt wear are these:


I love the way the rods are split:




Crank journals looks virgin




So how about those ring gaps?

I pulled the #1 and #2 rings off the #2 and #4 pistons. I check the ring gap at 1" and 3" depth (top and bottom of stroke). Sorry for the bad handwriting but you can see that the top rings have a very tight gap, even tighter than OEM spec and the bottom ring has a wide gap, in one case wider than OEM spec. I surmise that the wide lower ring gap helps the top ring seal and also reduces the chance of ring flutter. I was happy to see how tight the top rings were.

[rice_classic]

I have a new in box OEM shortblock that I will open soon and check the ring gaps on it. I'll follow up when I get a chance to get back in the garage.