I have some questions about turbo charging a Blue 253 v8
My intention is to build an engine to handle 10psi -15psi
So i wouldnt have a clue what to do to the engine as far as mods
What needs changing
how high can i go before i need to worry about copper gaskets
What are the best pistons and rings to use
I understand how it all fits up and works but not what to change to make it last ( a little while anyway )
The reason i am doing this is i have a rear mount turbo setup that i was testing on my VC commo it works really good! that good it only lasted 60 seconds in full booste before the rings gave way its running 8psi with no mods at all and it is very very good fun
Hopefully
Turbo 253
Started by
_the_new_a9x_replica_
, May 16 2008 10:53 AM
4 replies to this topic
#2
Litre8
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Thrillseeker
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Posted 16 May 2008 - 12:11 PM
I would seek out some expert opinions on this from people who have had first-hand experience with these sort of engines. The names Wayne Mahnken in Vic and Mike Vine in Qld come to mind (assuming they are still around).
#3
mr5000
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chief break-everything
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Posted 16 May 2008 - 12:40 PM
i was at pro stroke yesterday asking a few things he said blue v8 have the thinest sidewalls reds are better but blacks are better yet again
#4
TerrA LX
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Posted 16 May 2008 - 01:24 PM
Ask Struggler.
#5
Struggler
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Posted 17 May 2008 - 11:25 AM
To run 10-15 psi you really need to upgrade everything. You could run that figure for ages with a good tune but if it pings then you will waste the lot.
Don't worry about copper head gaskets, try to find some Holden tin gaskets, or use Cometic.
As for the best pistons, like I said, if it has a good tune you will get away with a lot. If it doesn't you will have trouble. I would start with some stock style flat tops as used in the factory low comp 253's. If you want to build a real beast use a forged 305 Chev piston and leave it down the bore a fair way. This will give you minimal compression and allow you to boost it heavily, however throttle response unboosted will be average. Use a quality Moly ring unless you want to go mad, then stainless or similar would be the go.
Personally I would hunt around for a good used low comp 253 from an HQ or J. Low comp 253's from this era had 8.0:1. Re-ring it if necc. and have a go. Be really conservative with timing (around 22 total with no intercooler) and run it rich as (11:1 at full load). This tune will make it last. The reason your rings failed is because you will have rattled the engine with too much timing.
Any 253 has heaps of cylinder wall thickness. Staind91 is talking about 308 blocks.
A turbo 253 has heaps of potential but I wouldn't spend a lot of money on it going to SBC pistons etc, it would be a lot more cost effective to move up to a 308 and use a 350 forged piston you could buy for minimal $ anywhere.
Please share some more details about your rear mount setup. Sounds cool. Is it blow-thru carb ?
Don't worry about copper head gaskets, try to find some Holden tin gaskets, or use Cometic.
As for the best pistons, like I said, if it has a good tune you will get away with a lot. If it doesn't you will have trouble. I would start with some stock style flat tops as used in the factory low comp 253's. If you want to build a real beast use a forged 305 Chev piston and leave it down the bore a fair way. This will give you minimal compression and allow you to boost it heavily, however throttle response unboosted will be average. Use a quality Moly ring unless you want to go mad, then stainless or similar would be the go.
Personally I would hunt around for a good used low comp 253 from an HQ or J. Low comp 253's from this era had 8.0:1. Re-ring it if necc. and have a go. Be really conservative with timing (around 22 total with no intercooler) and run it rich as (11:1 at full load). This tune will make it last. The reason your rings failed is because you will have rattled the engine with too much timing.
Any 253 has heaps of cylinder wall thickness. Staind91 is talking about 308 blocks.
A turbo 253 has heaps of potential but I wouldn't spend a lot of money on it going to SBC pistons etc, it would be a lot more cost effective to move up to a 308 and use a 350 forged piston you could buy for minimal $ anywhere.
Please share some more details about your rear mount setup. Sounds cool. Is it blow-thru carb ?
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