installing a BIG BLOCK CHEVY IN A C4

One solution I thought of is to use a Pontiac Trans Am Shaker Hoodscoop.
Early 1970-72.
Fully functional Trap Door on the backside.
Electric solenoids activated.
I have a complete spare 1970-1/2 TA shaker hoodscoop assembly.
Worth alot of coin $$$$.
 
I dont recall anyone having working windshield wipers on A C4 Big Block Chevy Swapped Corvette Grumpy.
Never on Digital Corvette.

Driving on the Highways here you often see Rain.
Hard heavy blinding rain downpours.
 
frequent applications of RAIN.X on frequently cleaned wind shields works wonders:D

220b848e-d007-4b0b-a4f3-9425451d6cce_1.76a466503dcd8944ee38186615ecbf79.jpeg

Let me look back through my notes, I can,t at the moment remember which wind shield wiper motor substitute we used but yes there is a way to install working wind shield wipers

https://www.corvettemods.com/C4-Cor...MI9cvT7an82QIVzbjACh3RkQLPEAQYAyABEgJVq_D_BwE
 
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My late bud Bill said he swapped a 396 BBC into a C4 Corvette too.

I seem to recall he said no windshield wipers though.
 
Its the Ultimate Sin Grumpy.
Ponch in a Vette.
Only you could 1/2 understand.
But its less wide than a BBC.

Low cost durable 100 % Ultra High Torque and Hp just not obtainable with SBC.
Too many problem areas to upgrade.
 
I also think a 500 caddy would be a potentially good match to the c4 corvette!
 
As I'm sure your well aware,
theres a great many people that don,t have the skill and experience to do the job correctly,
and Id bet the vast majority would not even notice if its been correctly installed that,
many people would never notice, that the engine in the car was not original if the jobs done correctly.
at one time I has a 496 BBC painted pontiac silverblue with a pontiac 389 stickers on the valve covers and air cleaner,
and you would be amazed art the number of people that never noticed, it was not the original engine!



the car looked very similar too these pictures, but I had the pontiac stickers
l71a.jpg

l71ba.jpg

l71ca.jpg

http://tech.corvettecentral.com/2015/11/67-69-tri-power-carburetor-tuningtroubleshooting/


EP-705139961.jpg&updated=201305130636&MaxW=800&maxH=800&noborder


64g3.jpg

65gtoa.jpg
 
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I have quite a Few Trans Am guys on TAC interested in C4s too Grumpy.
One guy with SD455 TAs bought a A nice White C4 Roadster last year.
He Proudly showed it off.
 
Setting the 427 Tall Deck BBC onto the stock motor mounts is the only easy part.
Accessory Drive.
Exhaust.
Dont have it yet.
 
I bought a set of original Ponch 1970-71 TA Motor Mounts or Frame brackets. Very Strong. Able to withstand 700+ Hp.

Rather keep it all Chevy in the Vette.

TA shaker is Ok.
Make it my Corvette for sure.

None have dared to take on Dodge.
Might as well be me here.
 
I want a Conventional Transmission Mount like a GM Musclecar has.
Just do not trust the 700R4 even though I built it myself and used best parts available at the time.

Turbo 400 Trans in.
Still Cruise & Brute Race Car Strength I need in a trans near bone stock.

Matt as You Recall from Digital Corvette used a TH400 when he Raced NMCA NHRA Setting world records in his C4 Corvette.

Use the Dana 36 for now.
Build the Dana 60 or Pontiac 9.3 rear.

Once I get the Tahoe fixed I will be able to tow the Vette From Eds garage to here as needed.
Lots of custom Fab work to be done.
We are talking again Grumpy.
I have a Ford 9 3rd member to setup after work this week for a project in his garage.
 
MARCH 31, 2009


In my last post I mentioned some maintenance work on my daily driver, and so I thought I’d share a bit on a project I hope to complete once the new workshop is finished – my other Corvette. I picked up this ’89 in 1997 refreshed the Z51 suspension with new springs, shocks and urethane bushings, then updated the J55 brakes with cross drilled rotors and EBC green pads, and ZR1 5 spoke wheels, 17X9.5 in the front, and 17 X 11 in rear. The six speed was rebuilt, and the heavy 33 lb dual mass flywheel was replaced by a single piece unit for an ’88 that was less than half the weight, along with a different disk and pivot ball since the flywheel was thinner by about 1/2″.

In 1998, I bored the stock 350 motor .030, and added Keith Black Hyper eutectic pistons, an SLP roller cam, full roller crane aluminum rockers and new guide plates, while performing a three angle valve job and minor port clean up on the stock heads. Long tube headers complimented the SLP big mouth intake, siamesed runners and heavily ported upper plenum matched to the dual 58mm throttle body. The factory magnesium rocker covers had internal drippers that did not clear the roller rockers, so I used the composite units from an LT4 and drilled a hole for PCV. This engine ran reasonable well, but the cam I chose probably had too much duration and even with an revised ECM program, never was pleasant to drive in rush hour commutes, and the overall combination just didn’t deliver all I had hoped.

In late 2003 the throw out bearing came apart and as I was between personal garages, with all my serious tools packaged away in storage, I decided to pay a shop to replace the bearing. Taking the transmission out proved to be a watershed moment because the Y pipe was fused to the headers and the shop had to all but destroy the pipe and part of the header collectors to get the transmission out. Ordinarily, this would have just meant a side trip to a muffler shop for some fresh pipe fitting, but I had another plan in mind since my college days. Why not load for bear and swap in a fully built big blog? Here’s how this came about…

I had a well prepared LS6 454 from earlier days gathering dust for over a decade in the garage, and I decided to rebuild it and transplant it into the Corvette.

I disassembled the engine and had the block tanked, checked and honed.

454block.jpg


I re-assembled with fresh bearings and rings. I had been running iron oval port head that had been fully ported and the bowl areas blended, but I wanted to improve performance and shed weight. I found a deal on some aluminum rectangular port heads on ebay that had been o-ringed and snapped them up.

454heads.jpg


I also picked up an arizona speed and marine tuned port injection system for the big chevy, along with the small external coil style HEI distributor for clearance. I upgraded to 36 lb injectors, and found a short style, reverse rotation water pump, along with a flat crank pulley.

So, facing the mangled exhaust on the small block, and having the fresh big block on the stand was all the excuse I needed to start the swap. Test fitting the new engine, there were three major interference points that I encountered. First, even with the flat crank pulley, the steering rack was in the way. I plasma cut the mounts, and moved the steering rack forward 1.5″ and rewelded it in place, adding some fabricated gussets on the front of the frame cross member to support the now cantilevered front mounting bolt points on the rack. An extra rag joint took care of the column spacing. We put it on the alignment rack and amazingly toe was only slightly disturbed while caster remained stable.

dscf0473.jpg


I wanted to retain the serpentine belt system, and the small block accessory brackets were useless, so I am fabricating my own – my prototype set are made out of steel, and I plan to mill some aluminum ones later. The power steering pump seen just above the alternator in the picture sits forward about 3/8 of an inch off the block face and the mounts are countersunk into a piece of plate. In a later post, I’ll show the completed brackets with some dimension and tips based on my trial and error. A gusseted riser from my power steering mount anchors one end of the factory upper alternator mount. The second interferrence point is the factory heater box – it’s fiberglass and easy enough to cut clearance relief out and glass back in the area, creating a “dent” that will clear the rear of the block and the #8 header primary tube.

dscf04711.jpg


The lower intake plenum, injectors, fuel rails have been installed. The intake ports that mate to the upper plenum and the distributor hole are sealed with duct tape. Alas, this project has been in limbo since early 2004 which I started work building the house as a pre-requisite to the shop, which is the pre-requisite to successfully finish projects like this one.

dscf0472.jpg


On the driver’s side, there is more room during the install, but not much. The windshield wiper moter must be removed from the firewall when installing the engine, but can be easily re-installed afterward. Dust, rust, and time are delaying me, bit I will see this complete.

Once mechanically complete, there will be a bit of paint and body work as well – there is a third interference in height. The big block intake is 2″+ taller than the combination it replaced, and so the stock hood must be replaced by a reproduction piece with 2.5-3″ more rise in the two center bulges. Once complete, it should appear fairly stock in outward appearance – no flames, wings or crazy paint to telegraph what lies beneath.

What should have been unrivaled five years ago is now obsoleted by the new LS7 powered ZO6 and the LS9 ZR1. Still, I expect to put down some healthy power figures and will have invested but a fraction of the $75-$130K price tag of GM’s uber vettes of today.
 
Thanks Grumpy.
Wiper motor can be reinstalled on Standard deck 427-454 we know at least.

Complete Mint 454s are real hard to find here today in IL.
Making friends On Facebook Chevy Groups when I spend time doing troubleshoot Tech there.
Keep an eye out for Goodies there.

Its a project once I jump into I have to get it done in 1-2 months running & driving.

The 425 Olds in the 63 GP was Tricky.
Never been done period just by Me.

Think I can pull it off BBC 427 Tall Deck in the 87 C4 Roadster.
Can upgrade parts later.
Setting up the Baseline and running & driving the plan.
 
The Ultimate Sin.
Pontiac V8 in a C4 Corvette.
Its never been done period.
It Fits who I am.
Since there is No usual engine crossmember below the oil pan its Entirely possible to pull it off.

Engine is less wide too.
 
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