Any down sidesto a 434 stroker
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Any down sidesto a 434 stroker
( FYI< I posted this in ENGINE MODS TOO)
The block I have is a 509 casting with 2-bolt mains.
Is this (434) taking a 2-bolt block too far?
The tranny is the 1985 4+3,,,, is it capable of taking a 434 stroker HP/TQ, any thoughts?
BTW, the cost for the 420 stroker kit is the same as the 434 kit but you dont see many 434's around.
Just curious!?
[Modified by ld85, 1:27 PM 11/24/2002]
The block I have is a 509 casting with 2-bolt mains.
Is this (434) taking a 2-bolt block too far?
The tranny is the 1985 4+3,,,, is it capable of taking a 434 stroker HP/TQ, any thoughts?
BTW, the cost for the 420 stroker kit is the same as the 434 kit but you dont see many 434's around.
Just curious!?
[Modified by ld85, 1:27 PM 11/24/2002]
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Any down sidesto a 434 stroker (ld85)
Don't think you want to go much over .030 with the stock 400 block. If your going to go bigger I would recommend a world product aftermarket block. It will run you 2K just for the block though. :cheers:
Racer
Joined: Oct 2000
Posts: 476
Likes: 0
From: Socorro New Mexico
Re: Any down sidesto a 434 stroker (ld85)
You will have to notch the bottem of the block too. Don't know how wise it would be to stroke a two bolt main that much. We are probably gonna hear from a couple hunderd people that have done that, now that I said it.
Look, by the time you do all the necessary work to that block, it will have been cheaper to buy an aftermarket block with all the right features.
Look, by the time you do all the necessary work to that block, it will have been cheaper to buy an aftermarket block with all the right features.
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Re: Any down sidesto a 434 stroker (Rynda)
Please see my response to the identical post in the "Engine Mods" section.
Indeed! For the umteenth time, in the 4.125" bore (400 cid) block, the 2 bolt block is stronger than the 4 bolt block. The reasons have been stated many times. I won't reiterate here.
Additionally:
4.125" bore X 3.750" stroke = 400 cid (stock 400 bore & stroke)
4.155" bore X 3.750" stroke = 406 cid (.030 overbore - stock stroke)
4.125" bore X 3.875" stroke = 415 cid (std bore - 1/8th" stroke)
4.155" bore X 3.875" stroke = 420 cid (.030 overbore - 1/8th" stroke)
4.125" bore X 4.000" stroke = 427 cid (std bore - 1/4" stroke)
4.155" bore X 4.000" stroke = 434 cid (.030 overbore - 1/4" stroke)
Id85, I hope these dimensions help clear things up.
RACE ON!!!
Don't know how wise it would be to stroke a two bolt main that much. We are probably gonna hear from a couple hunderd people that have done that, now that I said it.
Additionally:
4.125" bore X 3.750" stroke = 400 cid (stock 400 bore & stroke)
4.155" bore X 3.750" stroke = 406 cid (.030 overbore - stock stroke)
4.125" bore X 3.875" stroke = 415 cid (std bore - 1/8th" stroke)
4.155" bore X 3.875" stroke = 420 cid (.030 overbore - 1/8th" stroke)
4.125" bore X 4.000" stroke = 427 cid (std bore - 1/4" stroke)
4.155" bore X 4.000" stroke = 434 cid (.030 overbore - 1/4" stroke)
Id85, I hope these dimensions help clear things up.
RACE ON!!!
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Re: Any down sidesto a 434 stroker (Vic'89)
the 4+3 was used in the Callaway TTs, so it should handle the power, but maybe youll need to beef up some parts
I would just be worried about fitting it in there
I would just be worried about fitting it in there
Racer
Joined: Oct 2000
Posts: 476
Likes: 0
From: Socorro New Mexico
Re: Any down sidesto a 434 stroker (vader86)
Quote:
________________________________________ _______________________
Indeed! For the umteenth time, in the 4.125" bore (400 cid) block, the 2 bolt block is stronger than the 4 bolt block. The reasons have been stated many times. I won't reiterate here.
________________________________________ _______________________
For the umteenth time, thanks for the mini lecture.
Discussions are fine though.
It would not be that difficult for someone to pump 600 horsepower out of a 434 inch small block. That is about 100 horsepower more than I would want to treat the 400 two bolt mains to. Yes the Chevy two bolt mains are very strong and 4 bolt conversions are a waste of money for most street and bracket racing applications. But a little detonation at high horespower levels and you will have a bunch of souvenirs scattered all over the road/track. I agree that the two bolt main 400 blocks are stronger than the original GM 4 bolt 400 blocks. But, not the late model more recent stuff from either GM or the aftermarket.
Can the knock sensor respond quick enough to save the motor?
________________________________________ _______________________
Indeed! For the umteenth time, in the 4.125" bore (400 cid) block, the 2 bolt block is stronger than the 4 bolt block. The reasons have been stated many times. I won't reiterate here.
________________________________________ _______________________
For the umteenth time, thanks for the mini lecture.
Discussions are fine though.
It would not be that difficult for someone to pump 600 horsepower out of a 434 inch small block. That is about 100 horsepower more than I would want to treat the 400 two bolt mains to. Yes the Chevy two bolt mains are very strong and 4 bolt conversions are a waste of money for most street and bracket racing applications. But a little detonation at high horespower levels and you will have a bunch of souvenirs scattered all over the road/track. I agree that the two bolt main 400 blocks are stronger than the original GM 4 bolt 400 blocks. But, not the late model more recent stuff from either GM or the aftermarket.
Can the knock sensor respond quick enough to save the motor?
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Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Any down sidesto a 434 stroker (Rynda)
Thanks so much guys!
I just wonder why there were not too many 434'were around. I can build the 06 and I am sure it will be a streetable car that will be quick. My goal is high to get 12's minimum with out a lot of dinking around and I am certain the 406 will do this but curiosity go the best of me while shipping for rotating assemblies and I saw that the 420 cost the same as the 434 and wondered,,, why so?
I know that cost could be an issue but did not think that cost is the only issue.
Thanks again ! :seeya
I just wonder why there were not too many 434'were around. I can build the 06 and I am sure it will be a streetable car that will be quick. My goal is high to get 12's minimum with out a lot of dinking around and I am certain the 406 will do this but curiosity go the best of me while shipping for rotating assemblies and I saw that the 420 cost the same as the 434 and wondered,,, why so?
I know that cost could be an issue but did not think that cost is the only issue.
Thanks again ! :seeya
Racer
Joined: Oct 2000
Posts: 476
Likes: 0
From: Socorro New Mexico
Re: Any down sidesto a 434 stroker (ld85)
ld85: Sometimes we get so wrapped up in the "Walter Mitty" syndrom, that we forget to actually answer the question.
420 versus 434; Vic'90 has a good chart to refer to. The only difference was the 0.030 overbore. The 0.030 is the max recommended for the GM 400 block. Probably, the people that build these, want to bore out as little as possible. Once it is bored out to the max, there are no rebuilds left.
420 versus 434; Vic'90 has a good chart to refer to. The only difference was the 0.030 overbore. The 0.030 is the max recommended for the GM 400 block. Probably, the people that build these, want to bore out as little as possible. Once it is bored out to the max, there are no rebuilds left.
Drifting
Joined: Aug 2000
Posts: 1,316
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From: Houston, TX
Re: Any down sidesto a 434 stroker (Rynda)
I would think the main reason so many 406, 420 vs 434 is the cost. You can build a 406/420 with a cast crank. Don't think you can find a 4" cast crank, only forged. ck out the guys at allchevyengines.com, they have a 420 and 434 set up fairly reasonable.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Any down sidesto a 434 stroker (No Go)
Have you checked on what the machine work is going to cost for those strokes? Or the balancing?
Melting Slicks
Joined: Jun 2000
Posts: 3,215
Likes: 6
From: Tampa Florida
Re: Any down sidesto a 434 stroker (ld85)
Clearancing the block is what I was referring to. How close to the water jacket do you come with a 4 inch stroke...not sure if all blocks are capable...
Looking thru my Lingenfeltor book...it doesn't even mention 434...just the 420 and states the rotating assembly is little more special than other strokes due to clearancing...etc. It was published in 96 too.
I like my 406...
Looking thru my Lingenfeltor book...it doesn't even mention 434...just the 420 and states the rotating assembly is little more special than other strokes due to clearancing...etc. It was published in 96 too.
I like my 406...
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Any down sidesto a 434 stroker (No Go)
I have his book and was surprised NOT to see a 434. And then I saw that the prices for the 434 was not much more than the 420 and thats what started me wondering.
Just an FYI, the forged rotating assembly for a 420 is $1500 and the 434 is $1800. They are custom sets of forged pistons, rings, forged rods, main bearings and forged crank.
I will stick with the 406 and be much happier than I was with the stock 350CI/230HP stock 85 motor.
I would like to get a minimum of 300RWHP out ofthe motor and somewhere in the 12.XX's ET times.
Just an FYI, the forged rotating assembly for a 420 is $1500 and the 434 is $1800. They are custom sets of forged pistons, rings, forged rods, main bearings and forged crank.
I will stick with the 406 and be much happier than I was with the stock 350CI/230HP stock 85 motor.
I would like to get a minimum of 300RWHP out ofthe motor and somewhere in the 12.XX's ET times.
Safety Car
Joined: Apr 1999
Posts: 4,623
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From: Ohio
Re: Any down sidesto a 434 stroker (ld85)
ld, you will be pumping more than 300 RWHP with a 406 unless you run a really small cam with crummy heads. But it sure doesn't sound like you are planning on using less than better parts.
As far as your 4+3, it will soon be toast after that motor's in the car. A friend of mine put a Richmond 6 speed in his '85 to handle a well built 355 (13.5 : 1)with a radical cam. It's a roadcourse car that he uses for driver's schools. Can't imagine a 4+3 holding up to 1/4 mile duty.
As far as your 4+3, it will soon be toast after that motor's in the car. A friend of mine put a Richmond 6 speed in his '85 to handle a well built 355 (13.5 : 1)with a radical cam. It's a roadcourse car that he uses for driver's schools. Can't imagine a 4+3 holding up to 1/4 mile duty.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Any down sidesto a 434 stroker (h rocks)
Corky and I just mocked up my 406 the other weekend to check clearances. The connecting rods were lunati forged and they cleared the block easily, however the cam was a different story. On a few of the lobes they hit the connecting rods, the others had ~.028" clearance. We opted to clearance the rods a touch right at the shoulder where the bolts thread thu. This should give us another ~040" clearance. The cam was a TPIS .610 lift 242/242.
I think if you went with anything bigger you would have your hand full with grinding, both the block and rods. For something that is cranking out 600HP I would not want to take that much off the rods. But that is just me. I'm sure it can and has been done, but it would leave me feeling very uneasy. :eek:
A properly build 406 will put out some serious power, enough to make you forget about the 434, plus a little safety factor will make you feel more at ease while laying down the power. Just my .02
I think if you went with anything bigger you would have your hand full with grinding, both the block and rods. For something that is cranking out 600HP I would not want to take that much off the rods. But that is just me. I'm sure it can and has been done, but it would leave me feeling very uneasy. :eek:
A properly build 406 will put out some serious power, enough to make you forget about the 434, plus a little safety factor will make you feel more at ease while laying down the power. Just my .02
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Any down sidesto a 434 stroker (ski_dwn_it)
Corky and I just mocked up my 406 the other weekend to check clearances. The connecting rods were lunati forged and they cleared the block easily, however the cam was a different story. On a few of the lobes they hit the connecting rods, the others had ~.028" clearance. We opted to clearance the rods a touch right at the shoulder where the bolts thread thu. This should give us another ~040" clearance. The cam was a TPIS .610 lift 242/242.
My cam will not be nearly as "wild" I am doubting my lift will go over .510" max. I am building mine to be more streetable, I agree also that grinding too much on the block and parts can cause real strength issues.