What makes a high RPM engine?
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
2008 Ferrari Type 056 F1 engine specs: 2.398L, 90° V-8, cast aluminium block, 32 valves (pneumatic springs), bore 3.858", stroke 1.565", bore/stroke ~2.47:1
Oddly enough, the FIA has place a prohibition on titanium/aluminide valves to reduce expenses, but I suspect they be allowed once lower cost production methods are developed. 20,000 rpm, anyone??
Oddly enough, the FIA has place a prohibition on titanium/aluminide valves to reduce expenses, but I suspect they be allowed once lower cost production methods are developed. 20,000 rpm, anyone??
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
Oh..I dunno...pretty high sometimes! Seems the higher I rev it..the faster it goes! Ck the videos....they sound pretty cool if you crank up the volume!
Used to set the *shift suggestion* light at 6800 so I had a rough idea when I went past there. Then I would decide when it was time to shift.
Now I just unplug it when racing..just annoys me..never seems to go off for very long!
Let's see.....141+ mph..and remember...that's the AVG of the last 66' of the track....going to be going a little faster than that at the stripe.
My rear ratio is 3.07. My 4th gear is 1.435. My tires are 28". Might grow a little...but not that much.
Hmmnnn.....I get just about 7500 RPM in the lights. Ouch...did I just type that? Scares me to read it! Now you know why I don't want to look at any lights glowing!
Pump gas, steel rods, stainless valves. Valvesprings have been on it for 4-5 years. Just my little homebuilt street motor!
PS- I have a dyno sheets with WELL...I mean WELL over that RPM range when there were a few testing mistakes! Plus...what do you think it's like to be at 7000+ RPM in 2nd gear...and stick it back in 1st!! Seems like that may have happened once or twice over the years!
JIM
Used to set the *shift suggestion* light at 6800 so I had a rough idea when I went past there. Then I would decide when it was time to shift.
Now I just unplug it when racing..just annoys me..never seems to go off for very long!
Let's see.....141+ mph..and remember...that's the AVG of the last 66' of the track....going to be going a little faster than that at the stripe.
My rear ratio is 3.07. My 4th gear is 1.435. My tires are 28". Might grow a little...but not that much.
Hmmnnn.....I get just about 7500 RPM in the lights. Ouch...did I just type that? Scares me to read it! Now you know why I don't want to look at any lights glowing!
Pump gas, steel rods, stainless valves. Valvesprings have been on it for 4-5 years. Just my little homebuilt street motor!
PS- I have a dyno sheets with WELL...I mean WELL over that RPM range when there were a few testing mistakes! Plus...what do you think it's like to be at 7000+ RPM in 2nd gear...and stick it back in 1st!! Seems like that may have happened once or twice over the years!
JIM
What's the rod length? 6.385?
Race Director
Joined: Jan 2000
Posts: 13,022
Likes: 2,264
From: Corsicana, Tx
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Yep...6.385 rods.
The only thing better than a 327 at 6500...is a 540 at 7500 rpm!
Feed 'em some air...and they will breathe. Way too many folks have been reading way too many conservative Hot Rod magazine articles over the years. Made people build lots of expensive and slow cars!
JIM
The only thing better than a 327 at 6500...is a 540 at 7500 rpm!
Feed 'em some air...and they will breathe. Way too many folks have been reading way too many conservative Hot Rod magazine articles over the years. Made people build lots of expensive and slow cars!
JIM
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Modern world is great better flowing heads no porting needed even
as cast stuff is better then the old as cast stuff for airflow. Cranks, rods available with 4340 grade steel, even small blocks rods available
with 7/16 rod bolts. You see 4340 cranks, 4340 rods, forged pistons,
then you read hydraulic cam. Just because an engine has a cam
that can put in 7500/8000 RPM territory does not mean you have to drive it around at 7500/8000 rpm everywhere you go, but when
that hydraulic cam goes in you have just limited your chevy from what
it has always been good at. 4340 grade steel parts then limit your engine to 6000/6500 rpm.
as cast stuff is better then the old as cast stuff for airflow. Cranks, rods available with 4340 grade steel, even small blocks rods available
with 7/16 rod bolts. You see 4340 cranks, 4340 rods, forged pistons,
then you read hydraulic cam. Just because an engine has a cam
that can put in 7500/8000 RPM territory does not mean you have to drive it around at 7500/8000 rpm everywhere you go, but when
that hydraulic cam goes in you have just limited your chevy from what
it has always been good at. 4340 grade steel parts then limit your engine to 6000/6500 rpm.
Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
Modern world is great better flowing heads no porting needed even
as cast stuff is better then the old as cast stuff for airflow. Cranks, rods available with 4340 grade steel, even small blocks rods available
with 7/16 rod bolts. You see 4340 cranks, 4340 rods, forged pistons,
then you read hydraulic cam. Just because an engine has a cam
that can put in 7500/8000 RPM territory does not mean you have to drive it around at 7500/8000 rpm everywhere you go, but when
that hydraulic cam goes in you have just limited your chevy from what
it has always been good at. 4340 grade steel parts then limit your engine to 6000/6500 rpm.
as cast stuff is better then the old as cast stuff for airflow. Cranks, rods available with 4340 grade steel, even small blocks rods available
with 7/16 rod bolts. You see 4340 cranks, 4340 rods, forged pistons,
then you read hydraulic cam. Just because an engine has a cam
that can put in 7500/8000 RPM territory does not mean you have to drive it around at 7500/8000 rpm everywhere you go, but when
that hydraulic cam goes in you have just limited your chevy from what
it has always been good at. 4340 grade steel parts then limit your engine to 6000/6500 rpm.
A 4340 crank limited to 6000-6500 ???? These cranks are a lott stronger than the original forged ones and even they went to 6000-6500 no problem.
Most breakages btw occor at the rod due to high rpm, not at the crank. Better said, mostly the bolt or the lower cap lets go.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
A 4340 crank limited to 6000-6500 ???? These cranks are a lott stronger than the original forged ones and even they went to 6000-6500 no problem.
Most breakages btw occor at the rod due to high rpm, not at the crank. Better said, mostly the bolt or the lower cap lets go.
Most breakages btw occor at the rod due to high rpm, not at the crank. Better said, mostly the bolt or the lower cap lets go.
Yes, if you're going to rev, you need very high quality rods and rod bolts.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
I think you misinterpreted what Little Mouse is after. I believe he's pointing out the questionable practice of building a bottom end that will do the revs and then limiting the engine with a hydraulic cam. Why bother?
Yes, if you're going to rev, you need very high quality rods and rod bolts.
Yes, if you're going to rev, you need very high quality rods and rod bolts.
also my my 396, both with two bolt main blocks 5140 steel crank, I'm not sure what the rods were could have been 5140, maybe 1043, just old heavy TRW pistons that about everyone was running back then. I had a good friend ran his 327 chevy on the street/drag strip 331
with 11/32 rod bolts, sig eronson roller 5.13 gears, tunnel ram
two 660s, every other tooth off the syncros a Mr Gasket
vertical gate shifter, 63 nova. Can't remember any little 11/32
rod bolts or the two bolt main block failing.
4340 steel cranks, 4340 rods, 7/16 size rod bolts, then throw in
a hydraulic cam.
Last edited by Little Mouse; Jan 13, 2008 at 05:39 PM.
