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92 formula help 383 stroker

Old 01-15-2019, 11:26 AM
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92 formula help 383 stroker

Want to out 383 stroker in my car as the original l98 is old and tired - was wondering what issues I may run into if I get rid of the tpi setup and run the fitech efi system - will my factory ecu still work for the transmission tcc- speedometer?
Old 01-15-2019, 09:20 PM
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Re: 92 formula help 383 stroker

Don't bother with the 383. Just rebuild the 350 and change the cam and heads. 383 will increase the cost quite a bit for not much gain. Torque, yes - but you will likely have too much of that anyway with a built 350. HP gain is very small - like around 15 peak HP.

The TPI is fine - you don't need the FiTech. Check out the First intake:

https://firstfuelinjection.com/products

Get some larger injectors and run it with the EBL system from RBob. This way it's plug and play with the factory harness, etc.

GD
Old 01-16-2019, 03:25 PM
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Re: 92 formula help 383 stroker

Buy a GM L31 long block, a vortec base stealth ram and an ebl that Rbob sells. The L31 is an awesome deal when you consider how much it would cost you to rebuild an engine that would make as much HP. The ebl is great for starting out in efi tuning since its plug and play with enormous support on here. A Chinese base vortec stealth ram will also make more power and cost less than modifying a TPI setup.
Old 01-16-2019, 04:03 PM
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Re: 92 formula help 383 stroker

Originally Posted by GeneralDisorder
Don't bother with the 383. Just rebuild the 350 and change the cam and heads. 383 will increase the cost quite a bit for not much gain. Torque, yes - but you will likely have too much of that anyway with a built 350. HP gain is very small - like around 15 peak HP.

The TPI is fine - you don't need the FiTech. Check out the First intake:

https://firstfuelinjection.com/products

Get some larger injectors and run it with the EBL system from RBob. This way it's plug and play with the factory harness, etc.

GD
I do not necessarily agree. A 383 will make considerably more HP and TQ than a 350. Just takes more cam to bring the HP out of it which the long stroke and extra cubes of the 383 can tame and still have the same drivability of a 350 with a milder cam. Built with the same heads and cam your statement would be mostly true however. Keeping everything the same the difference is more like 25-30 hp with another 40-50 ft/lbs of torque and the 383 will shift the rpm for hp and torque peak down about 500 rpm.

Last edited by Fast355; 01-16-2019 at 04:08 PM.
Old 01-16-2019, 04:40 PM
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Re: 92 formula help 383 stroker

The problem I see is that on an otherwise stock car - transmission, suspension, traction, body stiffness, etc - shifting that torque down and making so much more of it really is just an invitation to have to upgrade everything else in the WORLD to handle it. Of course if that's what you want..... the cost of doing the stroker vs rebuilding the 350 will be significant, and I would argue probably pointless because the stock short block is unlikely to handle that much power without billet splayed main caps and other work...... personally if I'm going that far I might as well just get a Dart block with a larger bore that's already clearanced, has the priority main oiling, splayed caps, and so on.

It's not that hard to built a 400-450 HP 350 and that's about the limit of what I would suggest someone drop into their otherwise stock F body. And also probably close to the limit of what a stock 4 bolt block should be put through on a regular basis.

The torque shift.... great for a truck. Stump pulling, etc. But for the F body I wouldn't. Setup right the 350 has plenty of torque.

GD

Last edited by GeneralDisorder; 01-16-2019 at 04:50 PM.
Old 01-16-2019, 09:46 PM
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Re: 92 formula help 383 stroker

We'll what's the purpose of this car? 350 rear wheel horsepower (which a 350 can do) is plenty of power for these cars on the street.
Old 01-17-2019, 07:50 AM
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Re: 92 formula help 383 stroker

Originally Posted by GeneralDisorder
The problem I see is that on an otherwise stock car - transmission, suspension, traction, body stiffness, etc - shifting that torque down and making so much more of it really is just an invitation to have to upgrade everything else in the WORLD to handle it. Of course if that's what you want..... the cost of doing the stroker vs rebuilding the 350 will be significant, and I would argue probably pointless because the stock short block is unlikely to handle that much power without billet splayed main caps and other work...... personally if I'm going that far I might as well just get a Dart block with a larger bore that's already clearanced, has the priority main oiling, splayed caps, and so on.

It's not that hard to built a 400-450 HP 350 and that's about the limit of what I would suggest someone drop into their otherwise stock F body. And also probably close to the limit of what a stock 4 bolt block should be put through on a regular basis.

The torque shift.... great for a truck. Stump pulling, etc. But for the F body I wouldn't. Setup right the 350 has plenty of torque.

GD
Stud the 2 bolt and align bore it. Will not give an issue until the 500-550 hp range and more than 7,000 rpm. Even if you are building a 350 you will have to swap the pistons and should upgrade the rods. You can get a complete 383 rotating assembly for not much coin. Have a street fill done on the block before it is clearance for the stroker. With aftermarket rods the clearance grinding to clear a 383 is minimal.

A good running 305 can kill every driveline component on these cars and start to twist the chassis. Anybody building one of these cars up should already know they are going to be making massive changes to it.
Old 05-03-2020, 04:05 PM
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Re: 92 formula help 383 stroker

Originally Posted by Fast355
A good running 305 can kill every driveline component on these cars and start to twist the chassis. Anybody building one of these cars up should already know they are going to be making massive changes to it.

Specially the brakes!
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