Engine guru help
Thread Starter
Instructor
Joined: Aug 2007
Posts: 103
Likes: 0
From: Chatham On
Engine guru help
Hi all
Need some engine help and thoughts.
I have a local guy who races and has a engine for sale I can pick up but needs some work. It is what I have been looking for and is local bearing in mind it really is just a short block.
So it spun a rod bearing and is at the machine shop torn down and I have done an inspection. It does have pan, oil pump, timing chains Ect with it but no cam or heads.
First the machine shop guy says you can't machine the crank because a scat forged crank can't be turned? Sounds strange to me but the crank is a 4-350-4000-6000r
The block is a 4.125 SHP tanked plugged and ready to go back together no damage. It is still at 4.125 bore.
Callie's ultra 6.125 sj rods all look fine.
JE forged 213109 Pistons, look like 18 degree -2.5 cc domed Pistons.
I guess since this is going to be a pump gas motor any head options for those Pistons or am I looking at replacement and do I need to go oversize and hone to fit?
If I can find a head does it have to be 18 or should I go back to 23 ?
I suspect new pistons, hone and balance?
Anyhow opinions welcome.
The price is nice as well.
Mat
Need some engine help and thoughts.
I have a local guy who races and has a engine for sale I can pick up but needs some work. It is what I have been looking for and is local bearing in mind it really is just a short block.
So it spun a rod bearing and is at the machine shop torn down and I have done an inspection. It does have pan, oil pump, timing chains Ect with it but no cam or heads.
First the machine shop guy says you can't machine the crank because a scat forged crank can't be turned? Sounds strange to me but the crank is a 4-350-4000-6000r
The block is a 4.125 SHP tanked plugged and ready to go back together no damage. It is still at 4.125 bore.
Callie's ultra 6.125 sj rods all look fine.
JE forged 213109 Pistons, look like 18 degree -2.5 cc domed Pistons.
I guess since this is going to be a pump gas motor any head options for those Pistons or am I looking at replacement and do I need to go oversize and hone to fit?
If I can find a head does it have to be 18 or should I go back to 23 ?
I suspect new pistons, hone and balance?
Anyhow opinions welcome.
The price is nice as well.
Mat
Drifting
Joined: Jul 2013
Posts: 1,299
Likes: 93
From: Tri-Cities TN
Hi all
Need some engine help and thoughts.
I have a local guy who races and has a engine for sale I can pick up but needs some work. It is what I have been looking for and is local bearing in mind it really is just a short block.
So it spun a rod bearing and is at the machine shop torn down and I have done an inspection. It does have pan, oil pump, timing chains Ect with it but no cam or heads.
First the machine shop guy says you can't machine the crank because a scat forged crank can't be turned? Sounds strange to me but the crank is a 4-350-4000-6000r
The block is a 4.125 SHP tanked plugged and ready to go back together no damage. It is still at 4.125 bore.
Callie's ultra 6.125 sj rods all look fine.
JE forged 213109 Pistons, look like 18 degree -2.5 cc domed Pistons.
I guess since this is going to be a pump gas motor any head options for those Pistons or am I looking at replacement and do I need to go oversize and hone to fit?
If I can find a head does it have to be 18 or should I go back to 23 ?
I suspect new pistons, hone and balance?
Anyhow opinions welcome.
The price is nice as well.
Mat
Need some engine help and thoughts.
I have a local guy who races and has a engine for sale I can pick up but needs some work. It is what I have been looking for and is local bearing in mind it really is just a short block.
So it spun a rod bearing and is at the machine shop torn down and I have done an inspection. It does have pan, oil pump, timing chains Ect with it but no cam or heads.
First the machine shop guy says you can't machine the crank because a scat forged crank can't be turned? Sounds strange to me but the crank is a 4-350-4000-6000r
The block is a 4.125 SHP tanked plugged and ready to go back together no damage. It is still at 4.125 bore.
Callie's ultra 6.125 sj rods all look fine.
JE forged 213109 Pistons, look like 18 degree -2.5 cc domed Pistons.
I guess since this is going to be a pump gas motor any head options for those Pistons or am I looking at replacement and do I need to go oversize and hone to fit?
If I can find a head does it have to be 18 or should I go back to 23 ?
I suspect new pistons, hone and balance?
Anyhow opinions welcome.
The price is nice as well.
Mat
No deal here unless you got 1 fat wallet. Crank can be turned not a problem. the problem is a 6.125 rod and 4" stroke. That puts it at a .900CH and that does not work. Shortest CH is 1.00 using a 6" rod. A 1CH will lead to accelerated piston wear.
Your limited to an 18 degree head with those pistons. This puts you in expensive valvetrain cost except for the Brodix 18X head but they are still $2000 for heads plus other parts.
Drifting
Joined: Jul 2013
Posts: 1,299
Likes: 93
From: Tri-Cities TN
If those rod were in this engine and it is a std deck SBC then they could have stacked head gaskets to build deck height. Kaase stacked .300" of head gaskets 1 year to win the Engine Masters.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Le Mans Master
Joined: Oct 2010
Posts: 6,936
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
definitely not an endurance application.
Last edited by 7t9l82; Mar 20, 2015 at 06:49 PM.
Thread Starter
Instructor
Joined: Aug 2007
Posts: 103
Likes: 0
From: Chatham On
Is therep a way to easily check the deck heigth on a bare block?
Did dart make a SHP block in an odd deck heigth like an LS or something?
Now I am really curious as the machine shop took it apart and did not say anything was strange.
Did dart make a SHP block in an odd deck heigth like an LS or something?
Now I am really curious as the machine shop took it apart and did not say anything was strange.
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Drifting
Joined: Jul 2013
Posts: 1,299
Likes: 93
From: Tri-Cities TN
Winning Engine Masters is one thing, did John park his dyno motor over the winter and drive it the following spring? Did he drive it for 30,000 miles? I sometime wonder how long you have been building high performance motors. Its one thing to win on a dyno quite another to win a endurance race.....stack head gaskets and expect them not to have problems after many hours and multiple heat cycling......wouldn't do that with any of my long term builds, maybe a drag car but, not anything going road racing or participation in something like Hot Rod's Drag Week contest
So as far as engine building is concerned...out of the box thinking or "we got this pile of parts laying around lets put something together and make it work".....1 of the 2 methods of thought were used to put this thing together. IMO to the OP if he is wanting a good solid platform for your suggested 30K miles then the only thing I see worth anything in this build is the SHP block.
EMC example is engine builders can do some "abnormal" stuff to make things work. The only way this engine ever ran was with some "abnormal" thinking. You don't win following the herd.
Thread Starter
Instructor
Joined: Aug 2007
Posts: 103
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From: Chatham On
Thanks for the information.
I see the block, crank after turning, and the sub parts pan, oil pump, cam chains as the only things salvageable?
I assume a 4 in crank in the SHP block is doable as I see it a lot?
Thanks
Mat
I see the block, crank after turning, and the sub parts pan, oil pump, cam chains as the only things salvageable?
I assume a 4 in crank in the SHP block is doable as I see it a lot?
Thanks
Mat
Drifting
Joined: Jul 2013
Posts: 1,299
Likes: 93
From: Tri-Cities TN
I personally would never consult a street customer that is after performance and longevity to put a 4" stroke crank in a std SBC configuration block.