Need advise restoring 1971 C3 454

[scs2rescue]

Hello, I’m a new member to your site (by the way, good job to whoever put it together).



I’m in the process of restoring a 1971 Vette, T-top with a 454 TH400. There’s many areas I need help in:

• I plan on building the existing engine as follows: 496 cubic inch stroker crank, using exisiting #820 open chamber heads, high lift cam, 850 Demon carb, possibly headers. Horsepower goals are in the 500 to 600 range. I recently had the rear end freshed up with new bearings/seals. The TH400 will be rebuilt to handle bigger HP. My questions are as follows:

- Will the stock rear end & suspension handle this kind of horse power?



- I’m playing with the idea of re-gearing the rear end from 3:08’s to 4:11’s then replacing the TH-400 with one of the newer GM overdrive transmissions (I believe called 700R). Has any had any experience in using this 700R trans. in a C3 & will it withstand the 500 to 600 horsepower?



- The #820 open chamber heads are the large oval port type. I understand these can be ported and larger valves installed. Has anyone done this? Do the current head configuration flow well enough?



- I understand the aluminum radiators work best. Does anyone have a good source for these?



- Headers make horsepower & I’ll need a set to make this engine breath. Has anyone put headers on a 71 C3 454? It’s already a very tight fit with the stock cast iron manifolds. Headers look like a nightmare to install?



- I found a couple of sources for new 2 ½” exhaust kits on the internet. Can the car handle 3” exhaust from header to mufflers (keep in mind the exhaust runs through a cross member)? Do you have any sources?

• I need a source for all of the emblems, weather striping, bumpers, interior seat covers, center console, door & kick panels, etc, etc, etc. There’s probably hundreds of companies on the internet selling these items. I would like the best price but don’t want to sacrifice quality. Who has the best quality at a fair price?

• All of the vacuum junk under the hood will need some attention (wiper doors, H/Light doors, etc). Does anyone know of a good book on diagnosing these devices?

• Does anyone know of a good instructional book on fiberglass repair.

 

[BarryK]

I need a source for all of the emblems, weather striping, bumpers, interior seat covers, center console, door & kick panels, etc, etc, etc. There’s probably hundreds of companies on the internet selling these items. I would like the best price but don’t want to sacrifice quality. Who has the best quality at a fair price?

First of all, welcome to the forum


Sorry, i'm not very good on engine stuff to help you on the other questions but for the above parts you need you probably want to try Paragon, Corvette Central,Al Knoch, or Zip. These places tend to have better quality items.
I understand that on many parts Paragon actually bought the original molds from GM and are the only manufacturer for them. other places may sell the parts but are actually buying from Paragon and just reselling under their brand name.
Be careful on buying the real inexpensive reproduction parts you may find. a lot of times these are cheaply made overseas and tend not to fit very well and/or have a much lower quality standard. For example, on replacement bumpers the cheap versions use a thinner gauge metal and a much cheaper chrome plating that won't hold up as well. On weatherstripping, the cheap versions many times won't fit properly.
It's well worth the few extra dollars to get the better quality items and know it fits properly and will hold up. Nothing worst than spending the money, waiting for the part, and it doesn't fit right or you end up having to replace it in another year or so - all for a few bucks savings.
(btw, I don't know about the C3's, but on my C2 the bumpers are one of the items that Paragon purchsed the molds and is the only manufacturer for them. They cost a bit more than the cheap import reproductions but the quality is the same as the orginals)
For interior parts like the seats, door panels, etc the best is proably Al Knoch.

http://www.corvette-paragon.com/
http://www.zip-products.com/Corvette_Early/assets/html/homepage.asp?
http://www.corvettecentral.com/
http://www.alknochinteriors.com/welcome.htm

I hope this helps you a little and I'm sure plenty of others on here can help you with all your engine questions.

 

[Jack]

Welcome ... this is a great site that Rob put together ... with help from a host of administrators, moderators ... AND ... SPONSORING VENDORS. Just so happens our newest sponsoring vendor specializes in Aluminum Radiators for Corvettes. Tom DeWitt can fix you right up with a no-hassle, direct-fit aluminum rad. http://www.dewitts.com/ .
JACK:gap

 

[Richard454]

Headers & stuff

I HAD headers on my 71 big block 4-speed. THEY got very hot-to the point of melting the glue on the carpeting. Plus they didn't not fit very well-had to massage w/ a hammer to make fit(and I have NO power options). Not to mention that the headers run RIGHT next to your steering box and cook all the lube out-then you'll be rebuilding the steering box. Ask me how I know? I'm going back to cast iron. And unless you put a highrise intake you'll really not be able to take advantage of the better flowing exhaust (by the way you'll need a l-88 hood). If feel you have to run them -you will want to wrap them. And rather than run underneath the car-do the sidepipes.

Will the driveline hold up? It all depends on how you drive. Rolling starts is the only way to go-unless you have a lot of money and like to spend it, twice.

Again-How are you going to drive it. Oval ports ARE the way to go for the street-w/ all the torque in the usable range-where as the rect make the horsepower at higher revs. And rather than redo the originals (if you really want more HP) get some aftermarket alumheads. Takes 60lbs off the front end.

Bottom line- after owning my car for 20+ years-Stock was really the best comprimise!!!

For the vacuum stuff
http://www.docrebuild.com/

For all the other-
http://www.tld-corvette.com/ talk to James or Sam

Good luck-

Richard
PS-already sold my headers...but if you need a high rise intake or a L-88 hood let me know!!!