Weiand #8007 intake on a 273 (Several questions)

-
toolmanmike said:
You are overwhelmed because you want to build a fun street 273 and someone wants you to put a Super stock 273 combo together. Litz, you need to back up and re-group. Do a little homework before you pull the trigger. The combination of parts that you stated in your first post are not "budget" 273 friendly. Geez, How did this thread end up in a argument? You have a stock 273 and you want to add a 4 barrel and intake. Good! Add headers when you can. Another good! Install a 8 3/4 with 4:10's good and not so good. Your choice, The 4:10's are a stretch. You don't need that gear for it to perform well and you don't need to rpm the motor to make it work. I'm done here and I hope other members stop posting and leave the guy alone. Litz was just asking about carb size. PM me if you want help with your 273. tmm
Click to expand...
Thanks For the encouragement! You are exactly right. I'm going to stick with the basic plan that I started with and that is to add a 4bbl, carb,and headers to the 273. Second thoughts on a cam. After all the cam talk I'm going to wait a while. I already have an A body 8:75 complete with super stock springs. I figured I would drive it with that combo until I install the subframe connectors and at that time move the springs inboard When that is done and everything is in order. Interior, body prep, etc. I'll go with with a 360/TF But that's probably a year down the road. All I really want to do right now is add a little snap to it, get the chassis work done, and drive it for a while. Lots of things to do before I do the engine swap. Thanks, Litz
 
OMG, don't let these guys discourage you.

I drive with 4.56's on the street. Started in 1982 with a 72 Demon and it had 4.56's.

Still doing it today. Guys like ebooger have been telling guys you can't run lower than a 3.55 for decades.

I can tell you 100% that a 750 with mechanical secondaries won't kill your bottom end and make the car undriveable. You can then use the 750 on the 360.

The earth is not flat and just about ALL the mathematical formula to calculate carb CFM are wrong, have been wrong and will continue to be wrong. This is proven in the real world very day.

Nothing wrong with what you have planned. Headers, cam and carb plus your 4.10 gear sounds pretty normal to me.
 
yellow rose said:
OMG, don't let these guys discourage you.

I drive with 4.56's on the street. Started in 1982 with a 72 Demon and it had 4.56's.

Still doing it today. Guys like ebooger have been telling guys you can't run lower than a 3.55 for decades.

I can tell you 100% that a 750 with mechanical secondaries won't kill your bottom end and make the car undriveable. You can then use the 750 on the 360.

The earth is not flat and just about ALL the mathematical formula to calculate carb CFM are wrong, have been wrong and will continue to be wrong. This is proven in the real world very day.

Nothing wrong with what you have planned. Headers, cam and carb plus your 4.10 gear sounds pretty normal to me.
Click to expand...
Thank you for the reply Yellow rose. I have run 4:10 gears in B body Mopars for years and they were fine. This little Valiant won't see much freeway driving and I'm not worried about fuel economy so I'm going ahead as planned with the project. Thanks again, Litz
 
A 750 is only 750 cfms at 1.5" Hg which is pretty restrictive but at .75" vacuum it flows more like 550 cfm. The carb rating has nothing to do with how much air and especially fuel your engine will use. When you tune your engine it will have the proper fuel to air ratio anyways. Not saying to go with the 750 but I can't see why it won't work. Carb choice has more to do with hp level than engine size since hp needs the same amount of fuel and air no matter engine size.
 
273 said:
A 750 is only 750 cfms at 1.5" Hg which is pretty restrictive but at .75" vacuum it flows more like 550 cfm. The carb rating has nothing to do with how much air and especially fuel your engine will use. When you tune your engine it will have the proper fuel to air ratio anyways. Not saying to go with the 750 but I can't see why it won't work. Carb choice has more to do with hp level than engine size since hp needs the same amount of fuel and air no matter engine size.
Click to expand...


Common sense and fact from the great white north.

Thanks.
 
Last edited:
If he slaps that 750 DP on with what ever hwy gear he combined with STOCK converter has now with a even a decent dual plane & even headers it WILL be a ball less wonder off the line!!!!!!!!! Ever hear of volicty? & hurting it at LOW RPM? Been there! Done that! On a low compression 318! If he does it all at once (gears, converter, exhaust, cam & intake) then it will work alot better. As hes said just wants a little snapper now & a 750 will do no favors for him at ALL with a partly stock rest of the drive train! Come on man! Its also a LOW compression 273! Not helping anything!
 
There is a lot of good info here, but it won't be fun sifting through it.
The thing that may have gotten lost is that with 4.10s; 30mph,my favorite blast-off point, on account of it doesn't all go up in tire-smoke, yeah so, 30 mph is about 4100/4200 (in kicked-down to first),with 25.5 tires. By this rpm the engine doesn't much care about it's low compression, nor it's stall speed, nor a bunch of other stuff.By this point all it cares about is getting air in,the hardest job of all.
So a super-fast-rate solid lifter cam and a big carb,headers,and the biggest,fattest,most free-flowing exhaust will all help to make that happen.The key here is the 4.10s. And while I don't always agree with YR, I think he pegged "A" pretty good combo, without digging into the engine. It wouldn't be my combo, but for the price of admission, OP could do a whole bunch worse.
I mean what are we talking about here? Gears, headers, and a 4bbl,(any 4bbl,any intake, to get started). A little icing would be a TC to get some snap off the line. I see that as in the neighborhood of a G, plus labor where outsourced. Where on God's green flat-earth are you gonna buy this much fun for a grand?
OOps I forgot the pipes and mufflers, let's call it $1500
 
Last edited:
As I mentioned before hes not swapping everything at once! Also going to have a VERY hard time finding anyone that will build him a looser converter for his early small/corse spline 904! Sure from 30 punch any & all transition air flow probloms will behind that rpm easily. I don't know of many street "challenge's"that go from 30 punch. Maybe a roll, let alone an actual drag strip! He asked from the beginning on a combo. With a stock bottom end & no mention of a higher stall t/c. By all means strap on that 750 & mat it from a stop & wonder why no tire spin with current drive train. Also how can the same carb rating be tits for a 273 ("that dont need to spin close to 7k") be good on the 360??? The 750 is about balls on for the 360 unless he wants to really make power/wind it up. Just going from own personal experience here. From a stop(uunless a manual trans better get that out there) it will be a dog off the line. Needs port velocity to signal the carb or crazy accel pump shot to get it to move air in & signal carb booster. Smaller carb WILL do thay alot sooner in rpm range.
 
I got too much motor to floor it from a stop. If I do that I will bang thru the gears and hit 80 in about 6seconds and the tires will still be spinning.Or maybe I don't have enough suspension. Either way this is how I like it. I like to floor it at 30 and blast to 50/60 in a blaze of smoke and noise!That's my thing....
And if there is turns and sliding even better!!

Keep up, Sally! lol
 
Fair but ya dont have a low compression 273 eather is my point my friend! there's a hell of a diffrence between your 360 & his 273 or any 273 for that matter!
 
AJ/FormS said:
I got too much motor to floor it from a stop. If I do that I will bang thru the gears and hit 80 in about 6seconds and the tires will still be spinning.Or maybe I don't have enough suspension. Either way this is how I like it. I like to floor it at 30 and blast to 50/60 in a blaze of smoke and noise!That's my thing....
And if there is turns and sliding even better!!

Keep up, Sally! lol
Click to expand...


The blaze of smoke is from his crack pipe.

The noise I can't account for. The smoke is definitely from his crack pipe. And it's a big mother too.
Fully loaded and ready to burn
 
Fair enough
But I did have a lo-C teener with 340 cam and heads that with 3.23s was a dog until it got a few Rs going, and then, look out!
It was the same with my 292/508/108; it needed some Rs to show it's true worth. With 3.55s it was soggy under 3000. With 4.30s it was ferocious.

I still think YR is on the money
 
You must log in or register to reply here.
-

Back
Top