5.7 engine build

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viperredduster

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I am contemplating this swap and think I have came up with this.

5.7 hemi
stock heads ported
comp 268 cam
stock internals
fast self tuning with carb style intake
This would be over 500hp or am I dead wrong?

I also came up with needing
flexplate for 727
headers prob tti
motor mounts - i found mancini's but does some one make a solid mount
and oil pan

are these facts pretty accurate or am I lost
 
viperredduster said:
I am contemplating this swap and think I have came up with this.

5.7 hemi
stock heads ported
comp 268 cam
stock internals
fast self tuning with carb style intake
This would be over 500hp or am I dead wrong?

I also came up with needing
flexplate for 727
headers prob tti
motor mounts - i found mancini's but does some one make a solid mount
and oil pan

are these facts pretty accurate or am I lost
Click to expand...

Looks like you are on the right path...
I would add upgraded valve springs and adjustable timing set with new tensioner
may need different radiator too
uh.... oil filter adapter or block off plate and remote filter set up


Surely leaving something out... One of the other guys will chime in...:burnout:

Good luck
 
I just dont want to have to try and sell the 360 man, but I know it would be worth it big time.
 
I've been looking at a 5.7 swap too and have been putting together a spreadsheet of all the parts I think I'll need. Here's a fairly thorough list I've come up with:

Motor mounts
Exhaust setup (TTI header or some stock manifolds)
Oil Pan
Oil Pan Pickup (to match the pan)
Oil filter block off plate
Oil filter relocation kit
Intake (if going carb or in your case carb style injection)
Ignition (I think yours is taken care of through the FAST setup)
Flywheel (flexplate for you)
New starter (make sure it clears whatever exhaust you pick)

Now for the different stuff that's not necessarily engine related:

First of all I think you can only keep power brakes if you have the small pre 73 style booster, so you may have to consider either finding a new booster or going manual. Manual steering setup if you go headers, I think some have kept power with factory manifolds, but if you do so you have to change the new power steering pump to a lower pressure variety either through a pressure change kit (I think Mancini had them) or a different pump all together. And in your case you would need to update the fuel system to high pressure for injection (the main reason I was going with a carb setup).

Also, the 500 horsepower seems like it might be just a little optimistic, but I really can't say either way. I've been looking through all of Inertia's cam offerings and talking with them a little about it and with ported heads and their biggest cam they were making around 400 horsepower rear wheel on a stock 5.7 bottom end (and I think stock compression). That would be around 500 flywheel, but that is on a stock intake. The carb intakes don't seem to really stack up against the factory ones. There was some magazine article about it where they compared a factory 5.7 car, a factory 6.1 SRT, and I think the Mopar performance carb style intake and the carb style one was something like 40 horsepower and torque down from the other two. Still, you may have better luck, so please don't take my word to be worth anything, I'm just regurgitating what I've heard other places, lol.
 
boden said:
I doubt that cam will put you over 500 HP
Here is a Popular Hot Rodding article where they tested 3 different comp cams on the dyno. Power for the comp 268 peaked at 466
http://www.popularhotrodding.com/enginemasters/articles/smallblockshootout/0602phr_hemi/index1.html

It looks like you have a pretty strong combo already. I'm all for hemi swaps, but I think you would get more bang for your buck by stroking your 360 to add cubes.
Click to expand...

I checked out the cams and I could do the bigger one which would be closer to 500 and I had planned on doing headwork to the 5.7s..

But yes it would be cheaper to stroke the 360, and match a cam with my heads (after porting) and prob make just as much power if not more. Oh man I just dont think the hemi would be worth it until I make more power than the 360 block would like to handle.
 
Map63Vette said:
I've been looking at a 5.7 swap too and have been putting together a spreadsheet of all the parts I think I'll need. Here's a fairly thorough list I've come up with:

Motor mounts
Exhaust setup (TTI header or some stock manifolds)
Oil Pan
Oil Pan Pickup (to match the pan)
Oil filter block off plate
Oil filter relocation kit
Intake (if going carb or in your case carb style injection)
Ignition (I think yours is taken care of through the FAST setup)
Flywheel (flexplate for you)
New starter (make sure it clears whatever exhaust you pick)

Now for the different stuff that's not necessarily engine related:

First of all I think you can only keep power brakes if you have the small pre 73 style booster, so you may have to consider either finding a new booster or going manual. Manual steering setup if you go headers, I think some have kept power with factory manifolds, but if you do so you have to change the new power steering pump to a lower pressure variety either through a pressure change kit (I think Mancini had them) or a different pump all together. And in your case you would need to update the fuel system to high pressure for injection (the main reason I was going with a carb setup).

Also, the 500 horsepower seems like it might be just a little optimistic, but I really can't say either way. I've been looking through all of Inertia's cam offerings and talking with them a little about it and with ported heads and their biggest cam they were making around 400 horsepower rear wheel on a stock 5.7 bottom end (and I think stock compression). That would be around 500 flywheel, but that is on a stock intake. The carb intakes don't seem to really stack up against the factory ones. There was some magazine article about it where they compared a factory 5.7 car, a factory 6.1 SRT, and I think the Mopar performance carb style intake and the carb style one was something like 40 horsepower and torque down from the other two. Still, you may have better luck, so please don't take my word to be worth anything, I'm just regurgitating what I've heard other places, lol.
Click to expand...

Thanks man for the info, I am starting to think that it would be better off for this car which already has all the accessories to run the small block to just build that motor. I will just have to buy a hemi and put it in something else as a cruiser.
 
Also forgot the kickdown linkage, throttle cable power steering elimation of some type and an electric fuel pump.
 
Yeah, for my 4 speed carb conversion swap I've got it down to around $3000 to get the car running (hopefully). There are a few things I still need to double check and probably add in that I've missed, but you can figure probably around $4000 to be safe for a swap. You can knock it down a fair deal by going with stock exhaust, but that's really up to you. The main reason I'm really even considering it is the potential of the new hemis. I've found it to be quite a challenge to make a 450 hp small block that will be drivable on the street for a reasonable price, but you can hit 400 hp with just a cam on a stock hemi. The stock heads flow better than most high performance race small block heads, so there's more room to go up in power later.
 
honestly 500hp is not too far off with the 268 and a set of inertia big valve heads. We are talking flywheel numbers on an engine dyno minus the alt ac and and the other power robbing goodies. You won't find an aftermarket casting for the hemi head. And port design is critical you can easily kill the velocity if your not careful. (i sugest buying heads from someone)

now on the cam choice there are some fast (for a truck) trucks out there running the 268 but I personnly think there are better choices. I would call the vendors and discuss your plans and get a custom cam for your application. Then it can be matched to converter choice and will net you the most power for the dollar instead of a cam designed for a 5000 pound truck or a 4200 pound car.
 
03ramit1 said:
honestly 500hp is not too far off with the 268 and a set of inertia big valve heads. We are talking flywheel numbers on an engine dyno minus the alt ac and and the other power robbing goodies. You won't find an aftermarket casting for the hemi head. And port design is critical you can easily kill the velocity if your not careful. (i sugest buying heads from someone)

now on the cam choice there are some fast (for a truck) trucks out there running the 268 but I personnly think there are better choices. I would call the vendors and discuss your plans and get a custom cam for your application. Then it can be matched to converter choice and will net you the most power for the dollar instead of a cam designed for a 5000 pound truck or a 4200 pound car.
Click to expand...

Yeah I am not set on the 268 or anything for that matter, I dont even have the motor but I would like to run low 10s eventually and I think that the hemi would be more reliable at that level.
 
viperredduster said:
Yeah I am not set on the 268 or anything for that matter, I dont even have the motor but I would like to run low 10s eventually and I think that the hemi would be more reliable at that level.
Click to expand...

man I'll be adding twin turbos to my build. I currently have a spartan cam from inertia and heads from them as well. It will be backed up by a 727 trans. And about a 3000 stall converter. I'm shooting for low 10's but I have a feeling it will end up in the 9's and that will be on 5-7 psi. And should get really great fuel economy. Be easy to drive around town and blow the doors off just about anything I want. I think your goal of low 10's is doable. But it will require a really light car or a perfect setup. In order to get there with 500 at the flywheel. You could always add a bottle to get you as fast as you want just don't go over a 150 shot on the stock motor.

sorry about the tangent. Low 10's should be fairly easy with a hemi. And very stretable. Good luck can't wait to see it.
 
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