Thinking of going 4.1 what are the goods and bads??
- Thread starter thunderace31
- Start date
BlackBandit
God loves Buicks!
- Joined
- Mar 29, 2003
I thought the 6293's were just the SAE version of the 8445's. Maybe I'm wrong though. It certainly wouldn't be the first time. 
thunderace31
Banned
- Joined
- Sep 2, 2002
For those that are curious here is a link to the 4.1 litre build on Turbobuicks.com:
TurboBuicks.com - Build a Budget 4.1 Motor!
TurboBuicks.com - Build a Budget 4.1 Motor!
Thanks for the info!
Blocks are most definetly not as strong! Im going to need to find me a stock 3.8 block to redo
I have a 109 shortblock with a spun rod bearing if you are interested sitting in my garage
Please see the following post from Turbobuicks.com, which offers a dissenting opinion regarding the strength of a 4.1 "291" block:
Orlando_87GN
Resident Idiot
Join Date: Sep 2000
Location: Orlando, FL USA
Posts: 8,732
4.1's are cheap to buy and add 21 cubic inches compared to the 3.8 motor. Get a '291' casting block and enjoy extra power at any rpm range. They are equal to any 3.8 block with the right machining and prep. When I say they are equal I am referring to how cheesy all of the production blocks are, 3.8 or 4.1, doesn't matter.
__________________
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1987 Buick Grand National
Budget 4.1, 204/214 cam, TA-49 Turbo, Stockish Heads, V4, MSD50's, TH DP, JayJackson 62mm TB, Translator plus Extender powered. 3680# with pilot
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1987 Turbo T with 5300 miles
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1987 Mazda RX-7 Buick Powered of course!
10.79 @ 126mph Sold
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1993 Mazda RX-7 4.1 Buick Powered
Orlando_87GN
Resident Idiot
Join Date: Sep 2000
Location: Orlando, FL USA
Posts: 8,732
4.1's are cheap to buy and add 21 cubic inches compared to the 3.8 motor. Get a '291' casting block and enjoy extra power at any rpm range. They are equal to any 3.8 block with the right machining and prep. When I say they are equal I am referring to how cheesy all of the production blocks are, 3.8 or 4.1, doesn't matter.
__________________
------------------------------------------------
1987 Buick Grand National
Budget 4.1, 204/214 cam, TA-49 Turbo, Stockish Heads, V4, MSD50's, TH DP, JayJackson 62mm TB, Translator plus Extender powered. 3680# with pilot
------------------------------------------------
1987 Turbo T with 5300 miles
------------------------------------------------
1987 Mazda RX-7 Buick Powered of course!
10.79 @ 126mph Sold
------------------------------------------------
1993 Mazda RX-7 4.1 Buick Powered
thunderace31
Banned
- Joined
- Sep 2, 2002
Thanks for the info this is great!
I may still try this route it seems cheaper for some reason when I add up the parts!
If I did choose to go roller cam it will still work right??
Also what heads should I use?? Ported stock or GN1 or something else??
Im looking for as much power as I can get at say 23-26lbs of boost on alky
Thanks for the info this is great!
I may still try this route it seems cheaper for some reason when I add up the parts!
If I did choose to go roller cam it will still work right??
Also what heads should I use?? Ported stock or GN1 or something else??
Im looking for as much power as I can get at say 23-26lbs of boost on alky
I for one am going with a 4.1 with forged pistons, steel crank, billet main caps, converting to a 210/215 roller cam, but since it is going into a TTA I am going with ported 3.0 liter iron heads. Additionally, I am going with a Turbonetics T66 BB turbo, but money is tight so I am going to keep the stock TTA intercooler for now. I am in quest of 10 second et's with low boost.
If you have the money I would go with the GN1's.
Mark
thunderace31
Banned
- Joined
- Sep 2, 2002
Can I use the stock shaft mount rockers with GN1's if I dont go nutty with the cam?? Was think a 210 or something maybe no roller not sure yet $$ are super low here right now do to super low sales (THANKS GAS PRICES!)
Dont know where Ill end up but I want to be in the mid low 10's
Dont know where Ill end up but I want to be in the mid low 10's
What pistons are you going with? Ive read artiucle saying toonly go with a 208 with a 3.8, but the 4.1s would want some more cam wouldnt they?
I am not sure about the GN1's and using stock rocker arms...probably someone else can chime in on that.
The pistons are .030 over J&E's. I have been told that I should have selected a more agressive cam due to the 4.1 now being a 256 CID, but my TTA will be primarily a street vehicle, so I didn't want a lumpy idle, so I settled with a 210/215 roller cam kit from Full Throttle. The heads are going to have SB roller rockers with 1.6 ratio on the intake and 1.5's on the exhaust.
I can relate to money being tight. I initially planned to spend $8000 total on my engine project...I have surpassed that amount...ouch! But keep in mind I set my TTA engine aside and having the complete 4.1 long block combo to be dropped in place of the stock 3.8 litre. Lots of good parts have gone into this...hopefully money well spent...cause the wife will not let me do this again...that is if I still want stay married to her!
The pistons are .030 over J&E's. I have been told that I should have selected a more agressive cam due to the 4.1 now being a 256 CID, but my TTA will be primarily a street vehicle, so I didn't want a lumpy idle, so I settled with a 210/215 roller cam kit from Full Throttle. The heads are going to have SB roller rockers with 1.6 ratio on the intake and 1.5's on the exhaust.
I can relate to money being tight. I initially planned to spend $8000 total on my engine project...I have surpassed that amount...ouch! But keep in mind I set my TTA engine aside and having the complete 4.1 long block combo to be dropped in place of the stock 3.8 litre. Lots of good parts have gone into this...hopefully money well spent...cause the wife will not let me do this again...that is if I still want stay married to her!
I am not sure about the GN1's and using stock rocker arms...probably someone else can chime in on that.
The pistons are .030 over J&E's. I have been told that I should have selected a more agressive cam due to the 4.1 now being a 256 CID, but my TTA will be primarily a street vehicle, so I didn't want a lumpy idle, so I settled with a 210/215 roller cam kit from Full Throttle. The heads are going to have SB roller rockers with 1.6 ratio on the intake and 1.5's on the exhaust.
I can relate to money being tight. I initially planned to spend $8000 total on my engine project...I have surpassed that amount...ouch! But keep in mind I set my TTA engine aside and having the complete 4.1 long block combo to be dropped in place of the stock 3.8 litre. Lots of good parts have gone into this...hopefully money well spent...cause the wife will not let me do this again...that is if I still want stay married to her!
if you ont mind me asking how much were the pistons? I emailed them and they told me 900. Moneys tight and your plan was to spend 8000? Im moving into your house lol:biggrin:
I bought a 4.1 short block that had the J&E's included in the price, so I am not sure what they run. It was a package deal for a great price. J&E's, ARP rod bolts, ARP main studs, magnafuxed "291" block, High Volume Oil Pump Double Roller Timing Set, Eagle Forged 4340 Steel Crank, Center Billet Caps BHJ Balancer and J&W Flywheel. Even with the great price the $'s seem to get out control quick!
I bored mine .035 to a 4" which lowered my JEs to $550 because they use an off the shelf V8 forging.
