my new holley stealth ram has no rear coolant cross over to connect the heads. what the hell? it has the front crossovers. my tpis bigmouth had 2 front an 2 rear crossovers as well as the stock tpi base manifold. i searched around other guys pics an theirs is the same as mine so it must be ok i guess? does this effect cooling performance? will the intake gasket seal if the system cant flow thru, i mean will it build pressure an blow the gasket? why didnt holley put the rear crossovers in? am i totally missen something here as ive been out of engine building a few years but know how to build a tpi engine ,ive done a few. thanks 4 help in advance

good question, i know that some intakes have the rear crossover and some don't. in my eyes it seems better to have the crossover, but i would like to see someones input on this that has experience with the crossover. so im subscribed to this thread.

Virtually NO intakes have any kind of "crossover", or anything else, back there. Think about it... there CAN'T be one, because the distributor is in the way. Just having the water "cross over", is of no particular value, anyway. There's no pressure differential to make water flow through it, and both places are at the "hot" side of the cooling system.

A common racing technique is to add an "extension" to the water outlet, under the thermostat, with 2 hose fittings; and connect each side of the intake back there to one of the fittings. You'd just have to drill a hole in the manifold on each side and add a 90° hose barb. That essentially allows hot water to exit the heads at BOTH ends, and pass through the thermostat and to the radiator; rather than it only exiting at the front coolant passage on each head.

I have had no problems with my HSR setup so far. I havent heard any negative issues with the lack of rear crossover as well. As long as you have good gaskets and coat around the passage with alittle rtv, you should seal just fine. I know mine has

The lack of crossover shouldnt hurt too bad. Coolant will flow thru the back of the heads to the front. Everything is gonna get some coolant flow, so it should have no problems cooling. The rear crossover I think may actually help distribute heat alittle better to the coolant since its another passage to flow thru the motor, making the coolant able to pick up more motor heat. Without it tho, i dont think it puts you at risk at all. I think its just a minor helping addition to the cooling system but doesnt necessarily need to be there

look at your cyl heads sofa kingdom there are one opening at each end of the head correct? now look at you intake gaskets 1204 -1205- 1206 take ur pickthere are one hole at each end of each gasket correct? these holes in the gasket line up with the holes on the heads water flows just in front of the dist hole from one side of intake to other . now get off of ur sofa go into your garage anlook at any sbc gen1 manifold an look real good thru the large opening of the square hole an u will see light on other side ,i know because im lookin at a tpis bigmouth int an a stock tpi intake and i can see thru both of them front an back u do have an extra int lyin around dont ya

tocorrect myself i shouldnt say look at any sbc intake im just talkin a bout a stock tpi intake base an a holley stealth ram intake i realize not all come with the rear crossover but the stock tpi base does as well as the tpis base i have. but to say its impossible to have a rear crossover on a tpi system is simply false. i understand its perfectly fine not to have it,but when i opened the box an saw no crossover when i clearly took an intake off with a crossover i thought they screwed up an i was screwed cause i already started porting it.imo if the hsr is opened up right with a clear shot at the runner its gonna be a great intake.dont get me wrong its got small ports but this thing is meaty an imo it will respond well easy over 400rwhp its definately a show an go piece if done right not just cool wanna be piece. ya i knowblh blah blah but we will soon see what a stock hsr does compared to a fully ported hsr

The reason there's holes in the gaskets, is because heads, being symmetrical (i.e. can be either a right or a left head) have to have coolant ports at both ends.

Now: show me a small block Chevy intake - ANY intake, any year, any manufacturer, FI, carb, or whatever - that has a "crossover passage in the rear.

I can't imagine where you would ever get the idea that some intake you took off, had such a thing. Here's pics of 5 different intakes I just ganked off of eBay. They are, in order of apprearance, an Edlebrock Performer, a stock TPI lower, a stock square-flange one from the 60s, a Professional Products Crosswind, and a Weiand Stealth. No "crossover" passage on ANY of them.

If you know of such a thing, please show us; I'd love to see how they worked it around the distributor. I'm not saying it's impossible, just that I've seen literally hundreds if not thousands of Chevrolet intakes (big blocks are pretty much the same in this regard) of probably 100 different varieties, and never seen even ONE that had such a passage.

Oh, and this one I had to actually get up and physically go photograph... a TPIS product I have in stock. No "crossover" passage here, either. Sorry I didn't include it in the first group, but I guess I got a brain cramp at a critical moment and became even stupider than usual. Hard to believe I know; but it really happened. Dangerous.

i cant remember what my TPi manifold looked like...whether it had a crossover or not...but looking at pics i'm seeing two water passage crossovers on TPI bases

I'm seeing a HOLE there, that goes to those heater hose fittings; sure doesn't look like a crossover from above though. But maybe that one is.

This is where i got it from
http://users.erols.com/gcwestph/Intake.html

its a edelbrock highflow base. It does look to me that there is a under neath the manifold water passage at the rear of the manifold in front of the distributor hole.

OK cool; that's a first on me then.

I have now actually seen such a thing.

My learning for today... woo-hoo!! I try to learn at least one new thing every day.

this is the only one i've ever seen tho. not sure why but your right, it certainly doesnt look like its there from the top view. it sits under the runners

i know its very very hard to see from top of manifold or a quick peek,but the tpis bigmouth (i dont know about minirams for sure)has a crossover as well as stock tpi .man im glad i wasnt hallucinating thanks later.ps the stock hsr just was solid ,im not that computer literate an stuff so can pose quick digital pics like u guys

Most later factory manifolds seem to have it (TPI, TBI etc). I don't think they'd have gone to the trouble of added it if it wasn't beneficial. I think the crossfire intake had one too, and I believe it may have been connected to the front crossover by a passage along the bottom of the manifold. Though that may have been to warm the large plenum floor to evaporate puddled fuel