How high can a 16 V engine be revved?

[xero]

Sam most aftermarket single valve springs are around the 50-55lbs/ft seat pressure (TODA and supertech are both 54lbs/ft), so the larger lift on the single spring may not be able to cope with the constant pressure are high RPMs and you will end up with valve float.
most of dual valve springs ive seen around the 75-80lbs/ft mark (supertech are 78lbs/ft) and would be able to handle the extra pressure of the large valve opening and RPMs.

[Sam_Q]

I see, makes sense thanks for explaining it

[oldcorollas]

formula atlantic head has stock valves and no porting? confused....

or "US Stock" = off the shelf from a shop?

[racermr2]

Oldcorollas: Here in the U.S. Formula Atlantic heads are fully ported and use 2mm larger intake & exhaust valves. Unfortunately, the class Iam building this motor for does not allow the use of a F/A head. This restriction is the basis of my many inquiries.

[oldeskewltoy]

btw... having "tested" both the Toda, and the TRD, they each run about 140#s @ 10mm of lift. I have the actually specs on the TRD springs, on the Toda's, I just remember checking them for my OST-017 head, but don't remember the actual numbers... but 140 @ 10 was what seems semi accurate

PS - ALWAYS check! NEVER believe!!! Remember these are MASS produced... the general specs they meet, but when you are using cams that utilize more than 95% of the springs capability, if you don't check... its only your fault when it fails........

[racermr2]

btw... having "tested" both the Toda, and the TRD, they each run about 140#s @ 10mm of lift. I have the actually specs on the TRD springs, on the Toda's, I just remember checking them for my OST-017 head, but don't remember the actual numbers... but 140 @ 10 was what seems semi accurate

PS - ALWAYS check! NEVER believe!!! Remember these are MASS produced... the general specs they meet, but when you are using cams that utilize more than 95% of the springs capability, if you don't check... its only your fault when it fails........

Oldeskewltoy: I contacted Misano and they will not be open until Wegnesday, the 27th. I'll keep you posted. BTW would you or a forum member have a picture of a AE111 blacktop crank. I've never seen one but I've been told they are 2lbs lighter than a USDM crank. I was informed that the AE111 crank became the std. replacement world wide. I bought a new crank from my local dealer and when I took it out on the box it looked worse than the old USDM crank and was not lighter. It weighed the same as the old one(28lbs). What I want to do is determine if the blacktop crank is indeed lighter and "WHERE DID THEY LIGHTEN THAT CRANK!! I'll duplicate what they did if possible. As you know I've got a lot of coin tied up in this motor and I don;t want to leave a "stone unturned". Oh yeah, your question about rod length prompted me to research further and I've decided not to go with a long rod. Apparently Endyn discovered that long rods create oiling problems because of moving the piston pin higher into the normal oil control groove.

[oldeskewltoy]

Oldeskewltoy: I contacted Misano and they will not be open until Wegnesday, the 27th. I'll keep you posted. BTW would you or a forum member have a picture of a AE111 blacktop crank. I've never seen one but I've been told they are 2lbs lighter than a USDM crank. I was informed that the AE111 crank became the std. replacement world wide. I bought a new crank from my local dealer and when I took it out on the box it looked worse than the old USDM crank and was not lighter. It weighed the same as the old one(28lbs). What I want to do is determine if the blacktop crank is indeed lighter and "WHERE DID THEY LIGHTEN THAT CRANK!! I'll duplicate what they did if possible. As you know I've got a lot of coin tied up in this motor and I don;t want to leave a "stone unturned". Oh yeah, your question about rod length prompted me to research further and I've decided not to go with a long rod. Apparently Endyn discovered that long rods create oiling problems because of moving the piston pin higher into the normal oil control groove.

You've been told BS....... there are 2 OEM cranks, the early crank(40mm rod journals), and the later crank (42mm rod journals). There is no such thing as a lighter blacktop crank. Oh... btw... the TRD crank is even heavier then both stock cranks

40mm crank on top, 42mm crank below



Don't worry too much about the crank... because it revolves, the mass means less then it does with the pistons, pins, and rods (these all go up and down) Also be wary of cranks that are knife bladed... often times they get too light @ the counterweight to effectively offset the pistons/rod assembly.

Another reason why I recommended you stay in the sub 10k range is you can survive on a properly machined stock crank, going over 10k usually means you move on to a TRD, or similar type crank.

BTW... I've got some TRD parts available if you are interested. I'm helping Loynings clear out their attic

Largeport, underbody TRD throttles for one (email me oldeskewltoy AT yahoo.com if interested)



BIG SALE: I'm selling for a Portland race shop to make room - Hachiroku.net | Forums

I can also get "new" TRD cranks.... (new, old stock)

[xero]

Don't worry too much about the crank... because it revolves, the mass means less then it does with the pistons, pins, and rods (these all go up and down) Also be wary of cranks that are knife bladed... often times they get too light @ the counterweight to effectively offset the pistons/rod assembly.

Another reason why I recommended you stay in the sub 10k range is you can survive on a properly machined stock crank, going over 10k usually means you move on to a TRD, or similar type crank.

this.
ive got a stock smallport crank that has been fully balanced and some minor tidy ups (casting dags and the like) and easily spins to 9500rpm. be mindful of all the other bits you will need to upgrade to support this (i think you mentioned what you've done prior but CBF going back and finding it now)