tunnel ram stroker?

just throwin an idea out..i dont think ive seen anyone do it. would a 408 do good with a dual quad tunnel ram intake? strokers are good for bottom end and tunnel rams are good for top end (i think thats the way it goes.) so wouldnt that be the best of both worlds?

Probably the reason you haven't seen anyone do it is because no one makes a tunnel ram for a 351 based motor....It is possible using a 302 intake and spacers..

RACE tunnel rams are for higher rpms. they have shorter, bigger runners. The tall tunnel rams like the ones in summit and jegs and poking sky high through the hood are street rams. They have longer, thinner runners good for torque and bottom end. Ironically, the only real driveability problem is cold backfires on startup.

The street ram is basicly a stock intake with the runners straightened out and up (except they are singleplane, not dual plane like a true stocker)

Hood clearance is why they have low, curved runners on stockers. Ever see the 50's and 60's big mopar cross rams? the carbs were either ON the valve covers (short ram) or OUTBOARD of the valve covers (long ram). these were torque monsters, but couldn't rev past 5 g's if you paid them.

when you say stroker for low end, it's a generalization (pretty good one, though) if the heads wont flow high rpm levels of air, with a cam that's matched, then a real race ram will be a turd down low, then not have enough motor to use the intake. but put goooood heads on it with the right cam and now its a screaming power house. this is the more expensive way to build a tunnel ram motor.

It's all about a matched combo. use a stroker with non race heads and a street ram and you could have a torque monster that doesn't need to be revved past 5 1/2 or 6 grand. this is a pretty affordable way of building a beast. no need for spendy heads, cams.

so the questions are: Full race or streetcar? And will the budget support a big inch, high rpm build? I'm speaking in engine generalities here and admittedly don't know of any mystical ford recipes (all brands have a few) but that's my Engine Tech:101 speech.

Originally Posted by 69fury

The tall tunnel rams like the ones in summit and jegs and poking sky high through the hood are street rams. They have longer, thinner runners good for torque and bottom end.

???? Exactly the opposite is true. Tall tunnel rams poking sky high through the hood do not make good torque and bottom end. Even the description on Weiand's High-Ram tunnel ram (which is the one you referenced that Summit and Jeg's use in their combos) says, "NOTE: Due to lack of low-rpm torque, not recommended for everyday street use."
Generally speaking, the higher you raise the carb with an open plenum, the more you push the power band upward and kill off low-end torque. This is true with carb spacers and intake manifolds. Why do you think the low-rise dual plane Edelbrock Performer is designed for low rpm torque and the high-rise single plane Victor Jr. is designed for higher rpm HP? A tunnel ram is even taller than the Victor Jr. pushing the power band even higher.
The street cars I've encountered with tunnel rams are typically over-carbed and make no low-end torque. That's why I said on the other thread that you would get smoked red light to red light on a regular basis. On a Friday night, we used to go looking for street cars with tunnel rams to race. We used to refer to them as... All show and no go!

okay sounds like the tunnel ram is gonna be outta the question. so which would be the best intake carb setup on a 408w. a single carb, dual quad(w/ a regular sized intake), or a 6-pack? i know the single 4barrel will be the easiest to tune. ive already got afr185s that are more than likely goin back on it. probably goin with a roller cam and whatever else. id like it to run good on the track but still be able to take it out for a drive on the street every now n then. plannin on a TKO swap also if that matters.

The single 4 barrel is your best bet by far...They make very good power and will be the easiest to tune and maintain...Most guys like to run the vic jr single plane intake..These motors are so torquey they almost have too much bottom end for the street anyway so its worth the trade off to gain more on the top end in my opinion...Carb sizes are generally in the 750-850cfm range..

Originally Posted by frdnut

The single 4 barrel is your best bet by far...They make very good power and will be the easiest to tune and maintain...Most guys like to run the vic jr single plane intake..These motors are so torquey they almost have too much bottom end for the street anyway so its worth the trade off to gain more on the top end in my opinion...Carb sizes are generally in the 750-850cfm range..

+1
I agree that a Victor Jr. intake and a nice carb would be the best performing combination with your AFR 185's on a 408.
If you're set on running dual carbs, I would recommend the Edelbrock RPM Airgap dual quad intake if they make one for the 351W. And who knows, it might even work well on a 408!
What kind of car is this going in? Also, what kind of compression are you making, and what kind of cam are you planning to use?
It should be a blast to drive with that TKO!

good deal. sounds like a fair trade off from a lil bit of top end to low end. torque is more fun anyway. as far as compression goes, not too sure yet. im lookin for a good bit though. either flat tops or pop up pistons. id like to be somewhere around 12-12.5 comp. pretty sure the combustion chambers were originally 58cc but theyve been milled a good bit. its goin in a 69 mustang coupe by the way.

Originally Posted by hepcat69

as far as compression goes, not too sure yet. im lookin for a good bit though. either flat tops or pop up pistons. id like to be somewhere around 12-12.5 comp.

Are you planning to run it on pump gas?

Actualy tunnel rams work quite well and do make good low speed power and torque when tuned properly and when everything is selected right. Their have been alot of test in hot rod and car craft over the last few years.