[94' Cobra 351]

The main seals on my engine are going I will have to replace them. This garage quoted me $1,500-2,000, well after hearing that i decided to do it myself. I am probably going to pull the engine for convenience, and I was wondering if this would be a great time to stroke my 351 to a 408. From what I know stroking it just involves changing the crank, rods, rings, and I will probably leave the pistons. Anybody know how long of a job that will be? I am only home for a few weeks before I get stationed in Germany. Some links would be great. Thanks.

[Luvdmustang]

Originally Posted by 94' Cobra 351 The main seals on my engine are going I will have to replace them. This garage quoted me $1,500-2,000, well after hearing that i decided to do it myself. I am probably going to pull the engine for convenience, and I was wondering if this would be a great time to stroke my 351 to a 408. From what I know stroking it just involves changing the crank, rods, rings, and I will probably leave the pistons. Anybody know how long of a job that will be? I am only home for a few weeks before I get stationed in Germany. Some links would be great. Thanks.

wouldnt you have to get new pistons though?

[BWAL]

not necessarily

[94' Cobra 351]

i have seen a lot of kits that come with pistons, but i have keith black pistons and don't want to change them out

[Euroeater95]

Usually when you stroke an engine you have to increase the stroke of the piston and you also increase the bore of the cylinder. If you want to keep your pistons then you will have to get a new crank and shorter rods. I dont know what kind of horsepower that will buy you. Also I dont know if it is different of 351s but when you stroke a 302 you have to clearence the block for the increased stroke of the crank.

[1slo5.0]

You will have to change the pistons if you stroke it because of the change in stroke and rod length. The pin where the rod connects to the piston is moved up in the piston. If you wanted to do a low budget stroker you could use a 351W and buy a set of 302 pistons and a 3.85 stroke crank. You can then use the stock 351W rods and it will make 393 cubic inches with a 4.030 bore.

[94' Cobra 351]

would it be smarter to go 393 or 408? what would the HP gain be compared to the 351, and the HP gain between the difference of 393 compared to 408.

[1slo5.0]

Bigger is better. Going to a 408 just costs a bit more.

[94' Cobra 351]

do you have any idea what the HP gain would be going from 351-408? I think I might want to supercharge it after that but am not sure, should i set the compression higher? or make it around 8.5? Running that much HP, what sort of other things am i going to need to upgrade in order to handle the horse? i know i will need bigger injectors, maybe tranny?