The Official Hot Rod Thread - Part 3: Money Pit Anonymous

[ZachJ03]

Off subject but I finally got my pile up to CJ’s Racing Engines in Auburn and made a few dyno pulls a few weeks ago. The car made more than I was expecting for 10.5psi. It does creep a tad, I have seen 11-12psi before. This was my third and best pull, had tire slippage on the second pull. Tried uploading dyno vid to Photobucket and it isn’t having it. Still on a stock bottom end 302

 

[churchmouse]

Off subject but I finally got my pile up to CJ’s Racing Engines in Auburn and made a few dyno pulls a few weeks ago. The car made more than I was expecting for 10.5psi. It does creep a tad, I have seen 11-12psi before. This was my third and best pull, had tire slippage on the second pull. Tried uploading dyno vid to Photobucket and it isn’t having it. Still on a stock bottom end 302

How much will that stock 302 take...???

 

[ZachJ03]

Lol, it’s past it’s life expectancy, been together for 3 years now. The tune is solid and I keep RPM’s conservative (6k). The old myth is the block will split at 500rwhp. I think mainly due to guys getting carried away with RPM.

 

[churchmouse]

Lol, it’s past it’s life expectancy, been together for 3 years now. The tune is solid and I keep RPM’s conservative (6k). The old myth is the block will split at 500rwhp. I think mainly due to guys getting carried away with RPM.

Spin-em up like you hate them.
Stock rods have engineering limitations which is why serious builders step up to after market.
As you say, keep it realistic and it will live.

 

[ChristianPatriot]

Stock rods have engineering limitations which is why serious builders step up to after market.

 

[ZachJ03]

Spin-em up like you hate them.
Stock rods have engineering limitations which is why serious builders step up to after market.
As you say, keep it realistic and it will live.

Oh yeah, fully aware of factory bottom end limitations. If/when it splits then I’ll weigh bottom end options, aftermarket SBF based block and rotating assembly or Coyote. Guys are doing some pretty good stuff on Coyote+Tubo set ups. As long as the factory 302 bottom end hangs in there, I’ll stick with him. AFR’s are solid under boost, timing and RPM’s are conservative.

 

[thunderchicken]

Off subject but I finally got my pile up to CJ’s Racing Engines in Auburn and made a few dyno pulls a few weeks ago. The car made more than I was expecting for 10.5psi. It does creep a tad, I have seen 11-12psi before. This was my third and best pull, had tire slippage on the second pull. Tried uploading dyno vid to Photobucket and it isn’t having it. Still on a stock bottom end 302

Nice. Is what are you doing with the car? Street cruiser, street & strip, road racing??

You're right keep the rpms reigned in and it will live longer than rumors say. Some people just try to get too greedy with a stock block & rotating assembly

 

[churchmouse]

Nice. Is what are you doing with the car? Street cruiser, street & strip, road racing??

You're right keep the rpms reigned in and it will live longer than rumors say. Some people just try to get too greedy with a stock block & rotating assembly

They tend not to realize the rod stops the piston and reverses directing 2 times in every rotation. Not as hard stopping it on the down stroke and going back up. The failures happen (mostly) when the piston stops at the top and is pulled back down on the intake stroke. Tend to stretch the rod caps.

 

[ChristianPatriot]

They tend not to realize the rod stops the piston and reverses directing 2 times in every rotation. Not as hard stopping it on the down stroke and going back up. The failures happen (mostly) when the piston stops at the top and is pulled back down on the intake stroke. Tend to stretch the rod caps.

I was under the impression that failures like rods/blocks happened at peak torque not necessarily high rpm. Peak torque being the highest cylinder pressure and therefore most “power”. Whereas high rpm failures tend to be caused by oiling issues.

 

[thunderchicken]

I was under the impression that failures like rods/blocks happened at peak torque not necessarily high rpm. Peak torque being the highest cylinder pressure and therefore most “power”. Whereas high rpm failures tend to be caused by oiling issues.

Cyilnder pressure and rod stretch are IMHO both brutal on an engine. Especially when it has a power adder and run high rpms.

 

[halfmileharry]

Spin-em up like you hate them.
Stock rods have engineering limitations which is why serious builders step up to after market.
As you say, keep it realistic and it will live.

No guarantees of an afterlife either. Even with aftermarket.
We're in an area of unknowns unless we travel the beaten path and eventually that gets over the top boring.

 

[ZachJ03]

Nice. Is what are you doing with the car? Street cruiser, street & strip, road racing??

You're right keep the rpms reigned in and it will live longer than rumors say. Some people just try to get too greedy with a stock block & rotating assembly

Its just a street cruiser. It’s a blast on the street. Made a few passes last year at Muncie and got a best of 10.9@131.9mph leaving on no 2 step, no boost and no power shifts. Don’t plan on taking it to the strip much, just occasional cruises. Has a decent suspension set up and 275/50/15 ET Street R’s out back so it hooks in second gear and up on the street most of the time.

 

[jeffsqartan]

Where did you score the spindles?

Pull-A-Part on the east side of Indy. Just east of Keystone and 70.
https://www.pullapart.com/locations/indianapolis/

Yeah, that turbo 302 is probably on borrowed time lol
I imagine mine will be, too. And I'm only shooting for 350-400 rwhp lol

 

[churchmouse]

I was under the impression that failures like rods/blocks happened at peak torque not necessarily high rpm. Peak torque being the highest cylinder pressure and therefore most “power”. Whereas high rpm failures tend to be caused by oiling issues.

High RPMs will stretch a rod cap and allow the bearing to spin. Or the cap will just break. Or the rod bolts will fail. Stock pistons are heavy. Stock rods have a point they can no longer survive the harmonics/pressures being exerted. Main caps are the same. They are merely cast pieces. 2 bolt mains are much weaker than the 4 bolt offerings.
Cast cranks will fail due to twisting/harmonics.

In the day with properly prepared stock rods/cranks/lighter aftermarket pistons we would spin the guts out of a small block. They would take the abuse right up to the point where they didn't.

 

[thunderchicken]

Its just a street cruiser. It’s a blast on the street. Made a few passes last year at Muncie and got a best of 10.9@131.9mph leaving on no 2 step, no boost and no power shifts. Don’t plan on taking it to the strip much, just occasional cruises. Has a decent suspension set up and 275/50/15 ET Street R’s out back so it hooks in second gear and up on the street most of the time.

Nice. Sounds like a very fun little foxbody

 

[thunderchicken]

Pull-A-Part on the east side of Indy. Just east of Keystone and 70.
https://www.pullapart.com/locations/indianapolis/

Yeah, that turbo 302 is probably on borrowed time lol
I imagine mine will be, too. And I'm only shooting for 350-400 rwhp lol

Right on. I don't go there often, but it's only few minutes from my house

 

[thunderchicken]

High RPMs will stretch a rod cap and allow the bearing to spin. Or the cap will just break. Or the rod bolts will fail. Stock pistons are heavy. Stock rods have a point they can no longer survive the harmonics/pressures being exerted. Main caps are the same. They are merely cast pieces. 2 bolt mains are much weaker than the 4 bolt offerings.
Cast cranks will fail due to twisting/harmonics.

In the day with properly prepared stock rods/cranks/lighter aftermarket pistons we would spin the guts out of a small block. They would take the abuse right up to the point where they didn't.

Quality parts is of the utmost importance if you expect it to live under consistently high rpms. And as Halfmile mentioned even then stuff breaks.
I always recommend a little over kill. Get parts designed to handle a little more than what your intentions are

 

[halfmileharry]

Quality parts is of the utmost importance if you expect it to live under consistently high rpms. And as Halfmile mentioned even then stuff breaks.
I always recommend a little over kill. Get parts designed to handle a little more than what your intentions are

Overkill is mandatory considering I don't know one of us that's ever finished with these money sucking, noisy, always needin' work SOBs.
You build a house from the foundation up. Same with a car.

 

[thunderchicken]

Overkill is mandatory considering I don't know one of us that's ever finished with these money sucking, noisy, always needin' work SOBs.
You build a house from the foundation up. Same with a car.

That's the truth

 

[churchmouse]

That's the truth

And............if I know I have a buffer I will find a way to stretch it...