Hey guys I have a customer that has modified a SBC Dart block for reverse cooling. What are going to be the main challenges here to swapping it out with the LT1 block. He is wanting to simply swap the bottom end/block and keep everything else the way it is (heads and intake). He is running DFI, so ignition can be swapped if needed. I'm into the turbo world more then engine side, so I don't want to start answering questions with incorrect info when doing conversions.

 

An externally plumbed reverse cool SBC?

 

Im wondering here on this one..Is he going to run a remote water pump setup..I once saw a BMW 5 with a mopar swapped in and done like that..

What did he do to perform the changes in the water flow path?

 

Here is a good pic of the way to reverse cool a SBC/BBC motor....

http://popularhotrodding.com/enginem...r_emc_33_z.jpg

Bret

 

very interesting picture.I understand the benefits for hipo street/circletrack/low octane motors of reverse cooling.But what about on a nitrous drag BBC with c16 or nitrous 118 race gas?Like say theres a penalty for Big Chief style heads, so your running fact. style siamese intake heads with a healthy plate shot,and burning pistons occasionally.I wonder would it provide an extra measure of safety against poor dist. hot spots,or is a 250-400 shot gonna burn what its gonna burn?
Just throwing my drops into the bucket here.
FWIW someone sent me pics of a guy on the impala forums that had modded/welded an aluminum SBC to work LT1 style reverse cool[he was pushing 1000hp i think] when the subject was bench raced a while ago.Maybe someone can enlighten.

 

Guys check out the detonation, ignition timing thread by andy in here.... they should be linked.

stealthblack.... is it a valve angle rule or a BigChief type head rule? Something like the Dart 18* BBC heads could be a good way around this.

BBC don't have the same problem that SBC heads have in terms of hot spots on the middle cylinders.

Bret

 

BBC plate motors were burning #7 or #8,i cant remember which.this was before some of the new plates came out though,when everyone was just drilling the shi! out of big shot plates.
as far as the heads this is cut and paste
HEADS:
Two valves per cylinder maximum. The following are cylinder heads restrictions (1) No
splayed, symmetrical, or canted valve small block heads (unless its a factory style replacement)
(2) Hemispherical heads are prohibited (3) One spark plug per cylinder Max (4) All billet cylinder
head prohibited (5) No Pro Stock type small block heads.
Other restrictions: No Big Chief, Pontiac, Olds, or any symmetrical and non conventional style cylinder heads. Also includes Ford C & E Motorsport heads. No "Yates" or "Neal" SBF heads or similar heads permitted. *See weight breaks for special applications & add weight section for Cylinder Head applications on bottom of page.

So whether or not 18deg are legal or not is gray area,as 18deg is still "conventional style" but the class has been around so im sure its been tried or is allowed,ill find out soon.maybe I could go Smokey style with some creative emblem grinding.
My real Q was if this would really provide that much more detonation resistance in a motor such as discussed, i would think not--but have no exp with an experiment of that type either.

 

Sounds like the Dart 18* heads will work on a BBC.... That in itself should help detonation since you can get the chambers smaller with less valve angle so the dome can be smaller and the flame front should burn faster.

Also you might want to look at a direct port setup since you are getting issues in the rear cylinders it's either a distrubution problem with the N2O and fuel or just the fuel from the carb.

If you plumb the coolant so the front and the back of the heads get coolant at equal temps I would imagine that will help get rid of some of the hot spots in the rear cylinders. That pic is a great example of that.

Bret

 

So coolant comes out of the pump vertically instead of into the block, is Y'd on each side to connections at the coolant crossover passages of the intake manifold, and then comes out the bottom of the block on each side (stainless braided line) up to a water neck mounted on the aluminum plate? Interesting.

As far as the original question, the LT1-style heads and intake would have to be converted to standard coolant configuration (there's a web site covering this... http://www.lt1intake.com/services.htm) to work with the Dart block and then you'd have to use a flywheel/flexplate for a pre-'86 2-piece rear main seal crankshaft. As far as timing, you'd lose the Opti, so you'd need a crank trigger and a cam sync signal of some type, unless you wanted to convert the LT1 intake to work with a distributor while you were at it (see above web site). There are probably a few things I'm missing, but I've considered swapping an aluminum aftermarket block under my top end myself and that's as far as I got.

 

the dist problems were on a BBC a long time ago,and do not apply to any current motor,just an issue i thought was semi-relevant to the reverse cool aspect.class rules permit plate only,and its still a project in the planning phase.but ive hijacked this thread enough,so ill shut up now.thanks guys for the info,i hope it wasnt too off topic.

as far as above, many thirdgen guys use john millican's converted intakes and are happy with them.