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Discussion Starter #21
Back pressure is good. Valve springs are good for 40+ psi . 300lbs on the seat and 680lbs open.. Got 2.15 intake and 1.77 ehaust valves. The 4.090 bore is the lmitation for a bigger valve. Had to remove some deck area with chanfers for the 2.15. there all Inconel . I have no clue where the cork could be .

Where would you look?

The parts are all good. Billet crank with full counter weights. Carrillo rods with Carr bolts. The weak link is the stock block . They dont make an aftermarket one ..
 

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Back pressure is good. Valve springs are good for 40+ psi . 300lbs on the seat and 680lbs open.. Got 2.15 intake and 1.77 ehaust valves. The 4.090 bore is the lmitation for a bigger valve. Had to remove some deck area with chanfers for the 2.15. there all Inconel . I have no clue where the cork could be .

Where would you look?

The parts are all good. Billet crank with full counter weights. Carrillo rods with Carr bolts. The weak link is the stock block . They dont make an aftermarket one ..
Possible leak ? Gates working correctly?

Those are some big valves.
 

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Discussion Starter #23
Possible leak ? Gates working correctly?

Those are some big valves.
No header leaks or pipe leaks Hot or cold. Waste gate works great no leaks at all . It responds to more boost with any added .. I was thinking about putting a larger ratio rocker on the intake and leaving the exhaust the same . My thinking was to speed up the exhaust gases to pick up on spool time..
 

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Back pressure is good. Valve springs are good for 40+ psi . 300lbs on the seat and 680lbs open.. Got 2.15 intake and 1.77 ehaust valves. The 4.090 bore is the lmitation for a bigger valve. Had to remove some deck area with chanfers for the 2.15. there all Inconel . I have no clue where the cork could be .

Where would you look?

The parts are all good. Billet crank with full counter weights. Carrillo rods with Carr bolts. The weak link is the stock block . They dont make an aftermarket one ..
Any idea on valve weights?? That is not a lot of open spring pressure for an intake valve that heavy. Cam losing duration at same lift may not have helped this situation depending on how aggressive the lobes are. I would run a larger cam and turn the piss out of it, you'll break less parts at high rpm vs your current power band. When you had spooling problems did you try advancing the cam to give it more torque to get up on the converter?? Depending on transmission you may consider a converter dump valve plumbed into the converter feed if possible.
 

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Discussion Starter #25 (Edited)
Any idea on valve weights?? That is not a lot of open spring pressure for an intake valve that heavy. Cam losing duration at same lift may not have helped this situation depending on how aggressive the lobes are. I would run a larger cam and turn the piss out of it, you'll break less parts at high rpm vs your current power band. When you had spooling problems did you try advancing the cam to give it more torque to get up on the converter?? Depending on transmission you may consider a converter dump valve plumbed into the converter feed if possible.

Intake:135g exh:129g

Its a .3883 int and a .3707 lobe .

Its recomended install is on a 110 . Ive had it in on a 108 and a 106 . It seemed to be more explosive with less hoof upstairs. Didnt really help spool . But it came on hard lower in the rpm which i think is why i was going through cranks . Then i went for the billet..

I really dont think im having any problems with the springs because i dont have any valve float. Seats always look fine . Ive been as high as 44 psi...

I did look into the dump but never got the right info on it to know exactly what to do. I would still like to try it if i found out what the right parts are to buy. Its a turbo 400..
 

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Who spec'd the cam and who ground it?? I would have gone with quite a bit more LSA especially with that much boost. There are several threads on here about valve train spring issues that make an engine run kinda flat up top or even layover a bit without being completely out of valve control. Its generally weak springs or not enough spring for the rpm or valve weight. I definitely like the other cam better and would consider going even larger. When nothing else pans out or makes sense come back to the springs.
 

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Discussion Starter #27
Tim at Bullet cams spec'ed it and ground it. He designed it with a none aggressive rap so it would live on the street. He told me that he didnt want to go any wider then 114. He said it would take away from the lower end power. We knew the 198 ci motor needed all the help it could get before turbo ..

What open rate do you think i should go with if 680 is not enough?
 

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If you want to make power you'll need more RPM. My 120ci Honda made well over 1000hp to the wheels but needed 10k rpm. I used stock and ported heads. Didn't see much difference.
 

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I would consider just putting the first cam back in it for now along with the head porting. You said the new cam didn't improve spool so I would go back to what you had that will help extend the RPM range back up a considerable amount and more so with port work
Put the old cam in at 110 ICL.
 

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Discussion Starter #30
If you want to make power you'll need more RPM. My 120ci Honda made well over 1000hp to the wheels but needed 10k rpm. I used stock and ported heads. Didn't see much difference.
Thats what i was looking for . Someone that tried ported and unported .

Thanks man!
 

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Discussion Starter #31
I would consider just putting the first cam back in it for now along with the head porting. You said the new cam didn't improve spool so I would go back to what you had that will help extend the RPM range back up a considerable amount and more so with port work
Put the old cam in at 110 ICL.
I would like to do that. But the big reason i changed the cam was one of the lobs kept going bad . So after 3 regrinds i decided to go for a new one . So being i thought the cam was too big i went smaller. Man was i wrong.. O well win some lose some .. Ill put it back together and see how it goes. Next time i spring for a new cam ill go big and get the head ported ..
 
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