kawboy5792

Title says it all.

severe-1

I saw one at the turkey rod run in daytona. I had to look twice cause it looked like a factory install. 454 Crate motor.
It looks tight with the 350, but once I pulled the motor on mine, it looks fairly roomy.
I'm gonna add cubes via a stroker crank. Thats adventurous enough for me. :D

vader86

Its a very tight fit, but ive seen somebody with one before.

AquaMetallic94LT1

Its possible but its a VERY tight. The front crossmember has to be notched, requires a taller hood, and special headers.

TheCorvetteKid

A big block will fit. But there is a clearance problem with the bellhousing on the passenger side - I think the floor itself has to be notched. It's not impossible. Just difficult (and not cheap either).

You would probably be better off getting a Goodwrench or BowTie block from GM and boring and stroking it out to 427 cubic inches. The best of both worlds - huge displacement in an engine that you know will fit under the hood with minimal modification (and a heck of alot lighter than the big-block too). John Lingenfelter may even sell a complete motor like this. If not, I'm sure he'll be more than happy to build one for you (he's done it before using the aluminum BowTie block).

Just my $0.02.

lite blue

A 427 small block?
They need to make a drool smilie :D

yoslambo1@cs.com

wouldnt a big block make the handling suck? why not just put a stroker in? :confused:

grumpyvette

if you put a bbc with aluminum heads, intake and water pump in , in place of the standard iron small block you only gain about 50-70 lbs, not enough differance to cause any problems at all, , I have worked on several of these swaps now and Im in the process of getting ready to do another one,heres whats needed

steering rack mounts cut and rewelded 3/4" farther forward (that of course means the power steering pump lines/steering shaft, need to be extended 3/4" also)

small notch (starting at rear and going 3" forward from rear edge X 3/4"deep X 5" wide works well in rear top surface of (K) frame cross member to clear damper and pulley)(if you use an internally ballanced big block with the 6.75" dia. damper you can most likely skip the notch but with the 8" dia damper its necessary, and some oil pans will also require the back 1 1/2 of the (K) frame to be notched at an angle slopeing to the rear to clear them so youll probablly need the notch of some kind anyway)(and yes before you ask you could shim/modify the motor mounts up to get the clearance, but that would slightly raise the weight center and slightly effect the handleing, and that also makes the windshield motor and distributor clearance a bigger problem)

air conditioner shrouding fiber glass on pass side foot well around the air conditioning on the firewall needs to be modifyed for clearance, (the fiber glass cover from a LT5 makes this easy)(evaporator houseing cover)

1971 bbc vette exhaust manifolds and all brakets/pulleys (mods needed here)

oil pan needs to be only 7.5" deep max

3" hood scoop unless you run a low rise intake and carb or a low height efi system

for a step by step instructions with pictures get a copy of the august 1998 vette magizine article( starts on page 34)it helped quite a bit the first time

otherwise its almost a drop in deal, but keep in mind that youll need a bigger radiator, the trans will not last to long with that amount of torque and it may not pass emission testing and a small size starter is needed, and your windshield wiper motor needs to be replaced with a much smaller one,(I don,t remember where we got them but alittle measureing and a trip to the salvage yard took care of that problem, and no tall valve covers don,t work well!

btw install the short block then add the heads with it in the car its FAR EASIER THAT WAY than trying to install the long block

BTW the earlier cars like the 1984-86 (Im not sure what years exactly)dont have the heavier forward frame braceing above the stearing rack that makes this swap more difficult to do! I have worked on this swap on the 84, 85, and 86 cars so I know they work fine, the later cars like the 1992 with the heivier forward frame braces above the stearing rack look like they will be more dificult but still do-able with some extra work, btw theres a guy at ARIZONA SPEED AND MARINE that has one you might want to talk to .





















[Modified by grumpyvette, 3:34 PM 7/25/2002]

Wadoka

I'm of the opinion that unless you just have to have the appearance of those big, ugly, shapeless valve covers under the hood, you'll be happier with an LT1 or L98 worked out to 420-422 (takes a perfect ultrasonic-ed/magnafluxed/x-rayed block to get out this big) or grab hold and get the 7-liter LS1-derived C5R block from GMPP.

And yes, Lingenfelter does happen to make one of these - but no one has shoved one into a C4 yet that anyone has admitted to.

93TorchRedC4

:D Grumpyvette for president!!! I can't believe the info he just spilled out like that! I wish I lived closer to him, think I'd ask him to adopt me or something........... Great job Grumpy! :seeya

0ski_dwn_it

Is there any way for someone to post pictures of this mod!

I would love to put a merlin 509 in my vette. We have it in the chevelle and you can't believe the power that thing generates. Its only 9:1 compresson too, so nitrous would be a snap.

It pulling the stock chevelle through the 1/4 in 11.5 @117 and we were having problems with the ignition that day. We have since resolved that problem and figure it will be going high 10's at ~12x. That engine in my vette would be without a doubt in the 10 consistantly. With a small amount of juice 9's could easily be had. Pushing the juice, perhaps 8's!

Can't wait to see some pictures......It should be interesting and explain in further detail what was described above. Great information!

grumpyvette

heres a few that are in the records(search mode)


http://adcache.collectorcartraderonl...2/29097052.htm




[Modified by grumpyvette, 2:42 PM 7/23/2002]

0ski_dwn_it

that looks cramped!

1991Z07

I went with the Bow-Tie small-block for my 427 SBC, but I think the new Motown block is a better solution.

This is the link to it... http://www.worldcastings.com/docs/catalog/pg26.pdf 4.125" bore with .250" wall thickness remaining, 1" thicker webs for strength...raised cam for wild stroker cranks...all the goodies built right into it.

The REAL problem with motors this big is they break EVERYTHING behind them if the tires hook up. :lol: Before I EVEN think about dropping in the 427, I have to make the rest of the drivetrain as bullet-proof as I can.

While it is a nice conversation piece, a BBC in a C4 would not handle well. There are more than a few who have done the swap, and the front-end plows like a John Deere. To make it closer to the same weight as a SBC, you would need an aluminum block. An aluminum ZL1 BBC costs $5k for a bare block :eek: Add another $3-4k for heads, another $3k for rotating assembly and you have a SIGNIFICANT investment and it still isn't in the car!!!

A BIG SBC is the only way to go. With the aftermarket blocks on the market today, you can go to a 427 cu./in. and have PLENTY of power.

BTW...did I mention my machinist HAS another 427 SBC he built a few years ago in a Camaro? It has 18 deg. Brodix heads & a carb and cranks 764 HP & 695 lb/ft at the flywheel. :D We are confident mine will get me 800 HP due to better porting on the heads and the Stealth-Ram style intake we are putting on it.

Now I just need the ZFDoc to build me a Super-Duty ZF6 and Tom's Differentials to build a bullet-proof DANA 44 and we are ready to go.

NOW, if I could only win the lotto. :chevy


[Modified by Joe90, 4:01 PM 7/23/2002]

grumpyvette

Joe90
just a few points
an all aluminum bbc WEIGHS LESS THAN AN IRON SMALL BLOCK so the HANDLING IMPROVES

an aluminum head, intake and water pump bring a bbc engines weight to within 70 lbs of the stock iron small block, so handling is almost unchanged

any un-supercharged small block not useing nitrous or some other power adder that makes over 550 hp is highly likely to be at least somewhat unstreetable as a daily driver and your not likely to build a small block that makes "764 HP & 695 lb/ft at the flywheel" likely costs as much or more than a big block makeing similar power, look, http://www.sdpc2000.com/cart.asp?act...=1579&pid=1131
http://www.sdpc2000.com/cart.asp?act...=1579&pid=2597
http://www.sdpc2000.com/cart.asp?act...1579&pid=14349

Flareside

Grumpy, I've got a 650+ hp EFI Merlin 540 sitting in my garage that I've been thinking about putting into a C4. Do you know of any specific intake/carb or EFI combos and how much hood clearance they needed. I have an EFI modified Victor Jr. setup with wideband F.A.S.T. that just barely squeezes under a stock '68 C3 big block hood, and I'm wondering if it would fit under the stock C4 hood as well.

Will a ZF trans bolt up to a big block? I know the bellhousing bolt patterns are the same, but I don't know how the flywheel, clutch, etc. is arranged.

What have you done to increase cooling capacity? Thanks!

IMO, a 427 small block is in no way a replacement for a modern big block. 427 was the size of a big block 30+ years ago, not today. If we're in aftermarket block territory, the cubes start at 509 and go up from there. The 427 may make the same peak hp and torque, but at less than peak rpms the big block feel much stronger, seat of the pants in everyday driving.

-Joe


[Modified by Flareside, 11:39 AM 7/24/2002]

1991Z07

I think you MAY have missed the gist of the post Grumpyvette...

You may not think 70 lbs more makes a difference, but that is just about the weight difference between an L98 and an LT5. Compared to my Z07, a ZR1 plows like a John Deere in the turns. I've driven a few of them to know.... even with Z07 springs they don't handle that well in the turns.

I also stated that the ZL1 would cost around $5k just for the block and a total of about $13k just for parts....not including machine work...which could easily add another $2-5k depending on who does the work. A race-prepped Motown block costs $2125 http://www.theengineshop.com/content/pg10.pdf ...less than half the cost of a ZL1.

My 427 SBC will cost somewhere in the vicinity of your second link...about $13k when we are done. I spent $3k on the block, $3k for the rotating assembly, another $3k for the heads, and the intake system is going to cost another $1k. I'll figure in another $2-3k for machinist work.

I don't plan on it being "streetable" in any stretch of the word....it is a race car. I'll see the open desert with it and some track duty, but I will retire it from MOST street driving this next year. My Z06 will take over that duty soon.

Where the differential is is that you will have to spend a lot of time & money to convert parts over to even install the BBC. I won't have to worry about that...I can bolt it in without any modifications to the frame, firewall, etc.

Granted, a BBC C4 IS a conversation piece, but it is good for going MOSTLY in straight lines.

I understand the concept of a lightly modified BBC versus a highly tweaked SBC. You get a LOT more bang for the buck modifying the big-block. But if the handling of the car suffers and you need to spend a fortune to fix it, how is that better or cheaper?

I looked into this mod HARD for a while before making my choice.

No flames intended...I just think if you want a car that handles well and don't want to spend a fortune getting it to handle, a "big" small-block is the better route.

My $.02 for what it's worth...

grumpyvette

Flareside
I don,t have any exact measurements, but if you get a copy of that 1998 august VETTE magizine its got pictures of a modifyied accel efi SYSTEM THAT WAS USED AND FIT UNDER A STOCK HOOD JUST FINE! BY LOOKING AT THE PICTURES I WOULD ESTIMATE THE EFI SYSTEMS HEIGHT THEY USED IS ABOUT 5.5" TALL, AND THE GUYS WITH THE CARS JUST HAD CUSTOM RADIATORS MADE
Joe90
I SEE YOUR POINT BUT I RESPECTFULLY CHOOSE TO DISAGREE AS i ALSO HAVE ROAD RACED C-4 VETTES AND THE EXTRA TORQUE THAT A BIG BLOCK PROVIDES WOULD i THINK ALLOW A PROPERLY SET UP SUSPENSION TO AT LEAST KEEP UP WITH THE SMALL BLOCK IN THE CURVES AND WOULD EASILY ALLOW FOR PASSING ON THE LONG STRAITS AND COMING OUT OF THE SWEEPING TURNS. BUT IT REALY DOES NOT MATTER AS MOST OF THE TIME THE (OH WOW, LOOK AT THAT!) FACTOR AND THE STREET PERFORMANCE IS WHAT MOST OF THE GUYS THAT DO THIS SWAP ARE AFTER!


[Modified by grumpyvette, 1:59 AM 7/25/2002]

Flareside

Grumpy, thanks for the info. Do you know about fitting the ZF to a big block? Just how durable is it? Will it handle 550 rwhp?

grumpyvette

all the swaps I ve seen or worked on so far have used automatic transmissions the guy in the 1998 august VETTE mag article used a 4+3 manual trans but mentioned that he will swap to a ZF trans because the big block has broken 3 of the 4+3 transmissions so far! he mentioned that if you get good traction the stock manual trans wont last to long. Ive been looking for a E80 trans for my swap!


[Modified by grumpyvette, 2:45 PM 7/25/2002]