Are you still building that other 2.4LR shortblock?

 

I still have it. Debating selling off the block and crank now or building it and selling it. Don't need 2 spare motors haha.

I still REALLY want to try out a 2.4L to feel the difference but at this point I just want something reliable next year and the 63 block is way less prone to head gasket failures than the 64, at least when it's being beat on for 20 mins at a time.

 

This is simply not true. With the proper Oring and surface finishes, the 64 block is perfectly fine.

 

There's 120 thou more wall between cylinders on a 63 vs a 64. I've seen almost every local high power TA evo in the midwest fry at least one head gasket in the past two years. PA has fried like 3-4 head gaskets. RS won't even touch 64 blocks for anything over 4-500hp.

I'm not disputing orings don't work. They do. I don't want to go that route. They're expensive and require more special attention. I'd rather just take the extra seal offered from more deck area on the fire rings.

 

Do you have a preferred O-ring style (copper vs. stainless, receiver ring or not?) and head gasket for 4G64 builds?

I've always wanted the extra displacement and deck height of a 4G64, but I've heard so many conflicting stories about head gasket reliability.

 

Everyone I've ever talked to always says stainless > copper rings. You can't run rings without a receiver groove. Way easier to put the grooves in the head and rings in the block.

 

I had Headgames do a copper oring in the head. Its the same setup English Racing uses in their TA cars, one being a 4g64 based 2.3L (custom stroke crankshaft) until you get into the their drag motor setup which is meant for 4 digit nastiness and not really even applicable to a 4g64 block.

I saw pro awesome IG post last week that there engine *now* has an oringed head. Which implies to me it has never before been oringed. So IMO it's a solid bet their head gasket woes will now be over.

I have a half mile car that is a English Racing full bling 2.4LR in it. Makes 870whp/680wtq with a gen2 6466. We did 35-40 170mph+ 1/2 mile pass with that car at Coalinga in April this year, two were 180.XXmph. with the entire front end closed off except for the intercooler opening. Not even a hiccup. So RS motors not wanting to touch a 4g64 sounds like they just haven't done the development...

I get the desire to not oring your head @ayoustin. It does add complexity, and if you pull the head to check something, getting it resurfaced is no longer a simple operation. But saying the 4g64 is unreliable is incorrect and I will always correct that misinformation. The setup/build spec simply needs to be correct.

 

I'm not saying it can't be remedied. But at the end of the day, I just want my car to run and not spend months again chasing stupid issues. This is the first time PA has run rings to my knowledge.

When it comes to racing, reliablility is paramount. To me, I'm willing to sacrifice the extra displacement for the larger head gasket sealing surface.

I know my car won't be competitive next year, but if I can get through the entire season without a catastrophic failure or anything requiring a major teardown then I'll consider the season a success.

 

Receiver groove is a 2nd groove milled into the opposite surface. Figure 3 on page 2: http://www.engineprofessional.com/ar...Q216_60-62.pdf

As far as I know, it's more of an extreme setup. Definitely overkill for most.

 

Receiver groove 100% not required...

And copper works great.

 

I wouldn't run without a receiver groove. I've seen a ring blow out due to being crushed improperly. Just my opinion though.

 

Sounds like you've been around a lot of poorly built engines.

 

This was back in my Mazdaspeed days. Motor was put together by a reputable shop. Aluminum doesn't handle rings like steel does.

 

I'm personally a fan of the 4g63 block over the 64 to keep it simple and have more material between the cylinders.Also the oil squirters. There is a local car that has made 800-1000whp for a decade on the same longblock using a 63 block/94mm crank without any witchcraft. Its been pro tuned and has been run hard for 15-20K IIRC. Back to back street racing etc.

Machinist are a dying breed unfortunately. If you've got a solid guy then treat him right and hope he works another 20 years.

ayoustin, At the point you have everything apart why not sell the stock crank/pistons off and move into a 94mm crank. Its just going to make everything better and its well worth it IMO. You can thank me later .LOL

Also, If you are going to run a hard hitting stock frame turbo I would consider some Carrillo's. Low rpm/high torque can stress things. They are going to be lighter then stock rods and strong enough for 1100ish.

Carrillo Pro H are around 585 grams. H tuff's are 635 grams. Turbo tuff's are 672. A lighter rod is going to be easier on the bearings and rev quicker.

Whatever direction you go, make a list and look over everything twice. Your car will be back running soon enough and you can enjoy it.

 

I'm trying to avoid dumping money into this motor, I'd rather spend money on getting it machined properly and buying other stuff to increase reliability like a Fluidampr balancer and possibly a larger oil cooler or fan setup.

My coworker actually owns his own machine shop and I still have old co workers at McLaren's machine shop who do lots of sidework so I'm fortunate to be in the company of many good machinists who can take care of all the little machine work left to be done.

The 94mm stuff has crossed my mind but again, this motor will handle 600whp all day without issue as it stands.

There's plenty I'd do differently if I were starting from the ground up, but what I have now will reliably hold together and that's priority numero uno. The money saved buying this motor and finishing it vs starting from square one will buy me a lot of seat time.