Your price for the c4 parts is high. ebay has a number listed for $1500 or so. You could rebuild and add big brake kit for a lot less than your estimate.
When I had my frame modified in 06 there were only a very few doing the mod, but today many shops do.
The original frame, if not damaged is actually a strong frame capable of handling the HP you mention.
You can upgrade the stock suspension and it will be a very nice driving old Chevy, but not even close to the c4.
Good luck,
Jim
http://www.ebay.com/itm/1984-1987-C...172247646104?fits=Model:Corvette&hash=item281ac27f98:g:~1sAAOSwd4tUEIya&vxp=mtr

 

Consider a C4 front stub. For the rear a shock bar & good shocks.

IF you do decide on Vette IRS circle file the stock dog bones, camber rods etc & replace with Banski parts.

Good luck.

 

It REALLY depends on what you want the car to be when done and how much you're willing to spend. The C4 swap will inevitably cost more, but not THAT much more in the end.

I've been down both roads now. I modified my '56 with everything you mentioned (sans the 4 link) and I didn't like the way it handled or steered. I had Global West control arms, Viking coil-overs, power 500 box, rebuilt steering linkage (you'll need to do that too btw...didn't see that in your list), new urethane body mounts (if yours are shot, figure those in as well), side motor mounts (again, you'll also need that, especially for an LSx swap), transmission cross-member (put that on your list as well), rear shock cross-member (you'll want that if you stick with a live axle), big sway bars, Viking rear shocks, and Global West 2" drop leaf springs out back. I was also running 12" Wilwood disc brakes. In other words, I made just about every single modification you can to the stock frame and was just unsatisfied in pretty much every way. Handling, braking, steering/road feel...I just didn't like it. I guess for a cruiser it woulda been fine, but I have a big motor in my car and I like to push it...I just didn't feel confident driving it hard.

Also, the stock frame will handle 400-450HP easily, but you WILL need a new rear axle (different topic, I have a modified F*rd 8.8 in mine) with that kind of power for sure, so just include that in your budget now. I had/have a ~600 HP 420ci SBC in mine before I did the C4 front stub swap...so yes, the stock frame will handle it.

Anyway, Lazlo Nobi (classicedgedesigns.com) lives down the road from me about 60 miles so I took my car to him this past April for the C4 front swap. He sells front clips if you're capable of doing it yourself, but this is not something to mess around with if you don't have very good fabrication skills. If not, he can do it for you...he did mine and he does excellent work for a very reasonable price. If I had to do it over from scratch, I wouldn't have bothered with the bolt-on upgrades. In the end, you'll spend about the same amount of money in my opinion, but the C4, even though it's not the latest and greatest, is still 40 YEARS NEWER than the original tri-five design. 40 years of R&D is a long time! One can debate how much better, but ask yourself if you think a 1996 Corvette will have better suspension, brakes, and steering than a 55 Chevy and you'll have your answer.

You'll get a lot of different opinions on this for sure...again, it really depends on what you want your car to be in the end. I opted to stick with my live axle for now since I have a pretty high powered motor. I might do a 4 link someday. We'll see.

See here (for my lengthy swap thread...I'm not done yet btw!):
http://www.trifive.com/forums/showthread.php?t=158540

I believe NickP of Prime Custom Cars on here does these swaps as well. They both do good work.

 

Nothing wrong with C4 but I have had great success with bolt on's. I recommend you call Mark at SC&C and discuss your goals. He knows this subject pretty well... http://scandc.com/new/catalog/14

IMHO the reason most folks are disappointed with the bolt on route is because they did not correct the flawed suspension geometry of the trifive and all old muscle cars where born with.

Take a brand new corvette and deliberately put a bad alignment on it and see how you like it. It has the best goodies money can buy under it but you will be disappointed driving it like that I can assure you.

Church key above is probably the best source here about this topic of why a trifive suspension needs corrected.

I will note that I saw ride techs new street grip kit at goodguys a few weeks ago it also addresses the suspension issue by adding taller ball joints. It look like a nice setup for a budget minded person at around 2500$ it included springs, shocks, sway bars, delrin bushings & taller ball joints for stock arms.

Rocky

 

Rocky...just to be fair, I didn't like the brakes or steering either and I really wanted a big set of brakes with large calipers and rotors (13" or a bit more, which the C4 swap lets one do quite easily with C5/6 brakes...heck I might even put on C6 Z06 brakes some day for sh*ts and grins!) without spending another $2K as well as the feel of R&P steering without having to re-do that as well (over the 500 box...which I also didn't care for, but was leaps and bounds better than the 605 box I had before it).

We can agree to disagree on the suspension parts...it's been hashed out many times on the other board I do think for a good deal of fellows, the modified bolt-on route is a decent way to go.

 

Hutch I hope for all the effort and cost you have endured swapping out midstream after going bolt on first you are right about it being way better going C4. We should see soon enough you just about got her back together?
yours will be interesting to see how well the new front set up works with factory leafs. Please report back.

 

I don't think I'll have it done before this coming summer to be honest. Too many other things going on right now and it's starting to get cold up here in WY anyhow. Next summer.

 

Many that go the new frame & C4 suspension do it for show or go (autocross) but remember it will ride closer to a Vette than a 57. Lowering the car 2" all the way around, upgrading the suspension, brakes, adding shock bar and transmission mount and adding sway bar definitely front maybe rear as well, will give the car a better ride. Ride Tech was working on a new suspension for these cars send them an email. As mentioned earlier the F@rd 8.8" is a good conversion to handle the LS power. I have several links about that swap if your interested. Stock rear is 60" wide so a slightly narrower rear (58"-59")helps with slightly wider tires without tubing the back and if you want more you can relocate rear springs or go with a 4-link. Depends on what you want out of it and how much your willing to spend. If your frame is straight & not rusted out I would go with using it and spend that money elsewhere.

 

After adding up all the bolt on parts it added up to over $6000 for everything. so I went the C4 route with a ready to assemble frame from RR Frames, with 96 Grand Sport F/R suspension and a Rick's tank. Only $2500 more at this point, and hopefully a better end result.
http://www.trifive.com/forums/attachment.php?attachmentid=140979&stc=1&d=1476967021
http://www.trifive.com/forums/attachment.php?attachmentid=140980&stc=1&d=1476967379

 

What's RR frames?

 

The biggest problem I have is backwards from the really nice looking tri-fives. I have a great chassis, but only a rat of a body to bolt to it.
http://www.trifive.com/forums/attachment.php?attachmentid=141002&stc=1&d=1477002584

 

I don't have a show car and I don't do autocross, I just enjoy a car that is a kick to drive. My Newman converted 57 to c4 is all that. I have the 96 Grand Sport suspension with the Dana 44 rear end, the GS had 13 in" front disc.
The power R&P is great around town and tracks straight with two fingers at 90 mph, comfortably.
Jim

 

Jim...is your '57 mini-tubbed? What size rear wheel/tires are you running?

 

No tubbing was needed, 275/40/18 on 10 in. wide rims. plenty of room.
My frame

Jim

 

Hey Rescue Dog, are you saying that you are getting a complete C4 chassis for about$8500? I know very little and want to upgrade my 56 suspension but the prices on brand name complete chassis are running $15000 to $20000. I would prefer IRS and being an old competitive driver want this car to handle like a "sports car" within reason of course. Can you elaborate ror an old dummy?

 

http://rrframes.com/prices/

From his site - $7000 for a conversion on a bare frame + freight to VA. Add another $1500 to $2500 for a C4 suspension set depending upon Dana 36 or Dana 44. Now, rebuild the unit - bushing set is $250. Next, run brake lines, fuel lines, battery cable and so on. Add a Ricks tank - 22 gal with pump from Summit at $1500. Remember, it's a conversion, no different than your present frame. You still have all of the mounts for body, engine and transmission to get too. Paint.

Having said that, it's an alternative for certain.

Pictured here for your pleasure is the last 57 chassis I did. Powdercoated and all, it was over 20 out the door. It's all new steel.