What all is needed to make my 372 a 408? Specs inside.
#1
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I have under 250 miles on my motor but I am dropping it to cut the cowl and change to a turbo K-member. I was kind of thinking about going to a 408 while it was out.... motor was built for boost.
Here is what I currently have:
LQ4/9 block (unsure which)
L92 heads ported, valve job, blended, PSI springs
"Truck" crankshaft
Diamond #11551 -19.2cc, 4.005" Bore, 4.000" Stroke
Callies Compstar rods 6.125 2.100 .927
Melling oil pump
Comp cam 232/234 .595/.576 115+3
Crank, pistons, bore, rings?
Here is what I currently have:
LQ4/9 block (unsure which)
L92 heads ported, valve job, blended, PSI springs
"Truck" crankshaft
Diamond #11551 -19.2cc, 4.005" Bore, 4.000" Stroke
Callies Compstar rods 6.125 2.100 .927
Melling oil pump
Comp cam 232/234 .595/.576 115+3
Crank, pistons, bore, rings?
#5
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I am thinking they gave me the wrong receipt for the pistons. The receipt says, Custom order pistons- see 11551 but when I called diamond to get the specs they said it was changed and 11551 was shipped to my builder. The builder was well known and had an excellent rep before he sold.
Kirk/ Kurt at APE engineering in Michigan. This was before Chris bought the company and screwed it all up.
#6
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What is so baffeling? This is a question, not being a smartass
I am thinking they gave me the wrong receipt for the pistons. The receipt says, Custom order pistons- see 11551 but when I called diamond to get the specs they said it was changed and 11551 was shipped to my builder. The builder was well known and had an excellent rep before he sold.
Kirk/ Kurt at APE engineering in Michigan. This was before Chris bought the company and screwed it all up.
I am thinking they gave me the wrong receipt for the pistons. The receipt says, Custom order pistons- see 11551 but when I called diamond to get the specs they said it was changed and 11551 was shipped to my builder. The builder was well known and had an excellent rep before he sold.
Kirk/ Kurt at APE engineering in Michigan. This was before Chris bought the company and screwed it all up.
#7
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I guess I would assume Diamond's records are incorrect that they shipped #11551 to Kirk. The person I spoke with (at Diamond) seemed quite confused reading the notes that was in their system. The goal was to have the CR at 8.5:1 if I remember correctly (this was 2008). The motor was built and paid for and then sat there for 3 years until I resumed the build.
To be safe when I pull it in a month or so, I will have someone go through it to be sure but in all honesty Kirk was/is a stand up guy in the Michigan LSx scene. After I moved to Florida I lost touch with everyone up there so tracking down what little records I have has been difficult.
Back to the original question though.....If I want to go 408...what all do I need?
To be safe when I pull it in a month or so, I will have someone go through it to be sure but in all honesty Kirk was/is a stand up guy in the Michigan LSx scene. After I moved to Florida I lost touch with everyone up there so tracking down what little records I have has been difficult.
Back to the original question though.....If I want to go 408...what all do I need?
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#8
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I guess I would assume Diamond's records are incorrect that they shipped #11551 to Kirk. The person I spoke with (at Diamond) seemed quite confused reading the notes that was in their system. The goal was to have the CR at 8.5:1 if I remember correctly (this was 2008). The motor was built and paid for and then sat there for 3 years until I resumed the build.
To be safe when I pull it in a month or so, I will have someone go through it to be sure but in all honesty Kirk was/is a stand up guy in the Michigan LSx scene. After I moved to Florida I lost touch with everyone up there so tracking down what little records I have has been difficult.
Back to the original question though.....If I want to go 408...what all do I need?
To be safe when I pull it in a month or so, I will have someone go through it to be sure but in all honesty Kirk was/is a stand up guy in the Michigan LSx scene. After I moved to Florida I lost touch with everyone up there so tracking down what little records I have has been difficult.
Back to the original question though.....If I want to go 408...what all do I need?
Of course, the crank would need to be balanced and bearing clearances would need to be checked as well.
#9
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It's hard to say without knowing for sure what's in it already, but it looks like the rods would carry over, and if you don't mind having a 402 instead of a 408, the pistons would work too. If you must have a 408, you would need new pistons for a 4.030" bore.
Of course, the crank would need to be balanced and bearing clearances would need to be checked as well.
Of course, the crank would need to be balanced and bearing clearances would need to be checked as well.
I just want 400+ CI that is well built. It isn't a max effort car but I'd like to run 9's.
TH350, 4000 FTI stall, 12-bolt, full BMR Extreme suspension..etc
! AC, !Pwr steering....etc.
So, a streetable racecar.
#10
TECH Junkie
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Whatever the heck you got on there doesn't matter, clearly there is a lot of misinformation going on because you have a 4.00 stroke crank, but it's a truck crank, and you somehow have 372 ci. Regardless, what you need to do is have a 4" stroke crank with 4.030 pistons and matching rods to make a 408.
#11
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I'd tear it down and take some measurements and run some part numbers before I did anything. If you have a turbo on there now, why do you want the extra cubes? If it runs good now, leave well enough alone. Maybe change the heads or put a different cam in there.
#13
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Whatever the heck you got on there doesn't matter, clearly there is a lot of misinformation going on because you have a 4.00 stroke crank, but it's a truck crank, and you somehow have 372 ci. Regardless, what you need to do is have a 4" stroke crank with 4.030 pistons and matching rods to make a 408.
If I have the above spec Callies compstars, will they work? What do the numbers represent?