Yep, thermoquad would be my choice for all street driven cars.
road car cam for my 318
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Dan the man
Well-Known Member
Don't mean to highjack the op thread, but does the quadrajet work on the sbm? What dual plane intake manifold will a spreadbore fit without a adapter if possible? Thanks guys.
Professor Fate
Push the button, Max...
Of course they work on a SBM. They were factory equipment in the early '80s or so when Carter was having troubles.
Spreadbore dual plane? There's the factory cast iron manifold, Eddy Performer, later issue LD340, a bunch of MP M1s, Weiand Stealth, and on and on...
No idea why you'd want to willingly run a Quadrajunk though, maybe on a dare... Stick with a TQ.
Dan the man
Well-Known Member
Awesome, thanks. I must have over looked the weiand stealth.
My opinion is you will never in a million years feel the difference between a 112 LSA and a 108 LSA in such a mild build. However, the 112 LSA will have a better vacuum signal and operate vacuum accessories such as power brakes better than the 108 LSA all things equal. It's just not a decision I would dwell on for two minutes. I'd have one on the way already.
junkyardhero
Well-Known Member
yes. in fact the quadrajunk was factory equipment on several flavors of mopar in the late 70's and early 80's.
factory dual plane 4bbl intakes after 1970 are compatible. or the eddy performer, sp2p and weiand action plus just to name a few.
there are several that can fit with some grinding: weiand stealth, offy 360, LD340 (*faints*)
Dan the man
Well-Known Member
I looked up the edelbrock performer rpm intake and it said that he thermoquad will not fit, bummer. But I'm going to check out the other ones
Professor Fate
Push the button, Max...
Excuse me, it's the Weiand Action Plus. The Stealth will also accept a spreadbore, it just needs the secondaries clearanced.
Dan the man
Well-Known Member
I thought that it might be possible to get it to fit. I'm glad that I asked you guys and thanks for the help.
Professor Fate
Push the button, Max...
The Performer. Not the Performer RPM. Different manifolds.
Performer:
RPM:
Now back to our regularly scheduled thread.
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I am with Jim, posts # 14 & 17.
I would use the Isky mileage cam #3901-M. The low comp ratio is a big factor. Have your current lifters re-faced.
I doubt a TQ would give much improvement, if any, over the AVS2 carb, as the '2' has annular boosters which are very fuel efficient.
I would use the Isky mileage cam #3901-M. The low comp ratio is a big factor. Have your current lifters re-faced.
I doubt a TQ would give much improvement, if any, over the AVS2 carb, as the '2' has annular boosters which are very fuel efficient.
Dan the man
Well-Known Member
Thanks.
Funny someone mentioned "not a long duration", but when I read the OP's spec, the first thing I thought was _"that's a LOT of duration for a stock 318", despite having a modest to moderate lift for that application.
He may be retired by now but the guy that runs Oregon Cam gives great advice. His name slips my mind right now. He’s a wealth of information. Oregon Cam is still in business.
It is the overlap the defines vacuum. A 112 LSA with X degrees of overlap will have as much vacuum as a 108 LSA with the same overlap. If you read Vizards books he has data that shows what LSA (all other things equal) can do if you get it wrong. The difference between a motor that wants low LSA (because it does not have great heads and small valve diameter) and going to a long LSA (108 to 112 is a huge difference he did 108, 110 and 112 I believe) was over 20HP and 20 ft-lbs of torque. His data has shown that the highest sensitivity to optimal engine operation is LSA selection not valve opening events (remember the other key here is keeping overlap similar as that is what you select to decide where you want the power band). He is in the middle of this debate on his YouTube channel right now as Eric Weingardner is doing a cam shootout on his channel this week. Entrants design a cam for specific mule engine he has. Will be interesting.
He was still tinkering around the show earlier this year when I ordered a slant cam.
Well, with all due respect to the man, I have differing opinions sometimes as to what is "wrong". In this hobby, if you can tune, you can make lots of "wrong" things work very well.
I am confused, this is a 216/216 @ 0.050" with 110 degree LSA and you are saying it has low vacuum? What are you considering low? This cam should have more than enough... is the intake leaking or something?
My guess would be timing too far retarded. That's the culprit a lot of the time. Could also answer why it's sluggish.
Yep.
Like the carb tuning videos. He always starts with timing.
What distributor is in this car? Original? It likely could use reducing the mechanical advance so you can run higher initial timing and still max out at around 32-34 degrees. I did that to all my cars and it make a world of difference.
I don't know. I would just figure out where the initial needs to be and put it there. Likely it would have too much total at that point, but then you get the distributor out, weld and refile the slots. ......it's SO simple to do yet so many people lock up in fear of doing it. You don't have to worry about any fussy limiter plate to get hung up on anything or produce the wrong advance than what it's marked. You figure it out yourself and modify it accordingly. Everybody wants "plug and play" to the point that they don't want to actually do any work to get there and that always results in an underperforming engine. I run about 21 initial in my slant 6 and about 10 mechanical, plus "whatever" the vacuum can pulls in, which is about 20. Basically the same with the Ford 400 in my truck, but it has about 34-35 total, plus the 20 on the vacuum can. People get so scared of doing it and they don't stop to realize it's all grammar school geometry. Every bit of it. Just like degreeing a camshaft.
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