Not your father's SBC tunnel ram.

I have BTTT the two threads on intake runner length and tunnel rams for the street because there is a new player in town. Colorado Hot Rod Parts. They have cast up some individual plenums for Edelbrock SBC tunnel rams that seem to take a different tack to performance. The plenums are first cast individually, so there is no extra air space (and balancing of cylinders) and then they have put in a divider that splits the plenum in half essentially producing a two throat carb (with a vacuum secondary) for each of the paired cylinders.Go to coloradohotrods.com and check it out. Is it worth $1500.00 with carbs? Will it look traditional (kinda, but not quite)? Has anyone ever done a form of this modification to their tunnel ram?

John

 

Looks like the only thing coloradohotrods.com has for sale is their logo and domain.

 

A thousand pardons, no excuse. Try coloradohotrodparts.com/main.sc

That should work.

 

P.S. On second look, there might not be a divider in the plenums. That oblong hole might be feeding the paired cylinders. The mystery deepens.

 

BTTT for the night shift.

 

I'd say it looks like alot of good theory trying to make a tunnel ram act like a factory mill when real world driveability is the goal. There is no divider-it is a funnel that aims the carbs charge at the inner four corners of the Weiand runners. Clever.

Downside: 400-450hp max. which is no problem for the target audience.
Upside: buy a real single or dualquad Weiand plenum and it'll support a wilder motor

Certainly looks great. Not outrageous pricing for a new tunnel ram complete with 2 Quick Fuel Technology carbs, the dual fuel line, linkages, along with the velocity stacks and filter, gaskets and studs.

Using a Weiand base lends some security that the most basic requirements of the casting are well researched.

I dont think it's cheap, but i'd never say they were gouging people at that price.

just noticed they have a cheaper kit for those with a Weiand base already. I'd go that route if it was my money doing the talking.

-rick

 

Well, I looked harder at the pictures of the street tunnel ram plenums and there is in fact a divider. That means that there are four separate plenums cutting, as I said originally, cutting the carbs in half. It would seem that the inner four cylinders would get more fuel (and the 5,7 pairing 7 would be very lean). Why they would run a pair of 570 cfm, vacuum secondary carbs is a mystery. I would think that a pair of 450 or even 390s would be better. Maybe a pair of 500 cfm Holley two barrels.
Also lets see any home made tunnel rams. Hamb home made, not Chrysler engineer made hemi tunnel rams.

John

 

What happened to Porknbeaners entry? I was going to refer back to it and it disappeared.

 

Hi - I am the guy who built the Real Street Ram.
The 580CFM carbs are there because you need about 300CFM to feed each pair of cylinders. Basically you have to size the carbs to deliver the peak airflow that the cylinders need on an induction event.

We did a huge amount of work to get the fuel distribution even and the fuel curve right. The convergent/divergent shape of the plenums is to get the fuel to distribute evenly between the pair of cylinders connected to it. Each venturi is also set up custom to deliver the right fuel curve based on the firing order of the cylinders connected to it.

 

photo spacers by dashman/hamb

made spacers out of wood years ago......

 

I just ordered one of these the other day. I will soon know if they work as advertised. I'll post how it turned out once it's up and running.

 

Did it work ok? I have been thinking about ordering one of these, is it responsive from idle like they say.

 

Try a PM, its been almost a year.

 

Why, cant he answer on here im sure other people would like to know.

 

He has no way of knowing that you posted here except by chance. If you PM him and he is still active he will be alerted. If he has it set up to his email account he doesn't even have to be on the Hamb to get an alert. Just trying to help and please post what you find out.

 

What Wraymen said.

 

He was on here last Sat. evening but that don't mean he checked back on this thread.

 

Got ahold of kaboo, he has it up and running sounds great and he said it's real responsive and idles nice