Inliners International Forums General Discussion Hi Performance built 292, looking for more!

my current build has .040 lp pistons and block decked .030 with guestimated compression at/below 9.5:1. 1.94 valves, no lumps, Langdon split manifolds, offy intake with dual webber 32/36 and Clifford 264 cam. HUGE improvement over the stock 250 but not all I had hoped for. the cam is only 206 @.50 and this concerns me. I have ran a comp cams 268 (218@.50) in a 250 and was not at all over cammed. I suspect the cam is my biggest issue but need advice. lumps? are they worth the effort on something that will never see 6k? I know the offy is less than desirable but am limited on space, it is in a '64 chevy van and Clifford intake would be very hard to make fit. I have considered adding lumps, some porting and decking the head but unsure of actual gains so looking for input on all or anything I am overlooking.

The lumps help at ALL RPM's. They can add almost 15 ftlbs tq.
Porting will probably help also. It depends on what was done when the larger valves were installed.
Decking the head might not be needed if the block was cut .030 and you have LP pistons.
That short duration cam and higher compression may not play well with detonation.
What distributor are you using? Trans and rear gears?

builder insisted not to go any higher on compression. he took off enough to true up the head and did very minimal porting. I wouldnt remove head only to shave .020 but if its off for lumps and porting anyway? I have a stock h.e.i. dist. and coil, have done 'some' tuning but had little effect. I left it at 36 degrees total at 2500 rpm. 200r tranny with 3.36 gears. I have ran a 4.10 rear but it simply goes straight to second gear. 3.73 'someday' but those are what I have in my shop. engine between front seats, it has to come out for a cam swap. would like to swap that while head is at machine shop. van weights 3400 lbs. and is driven daily when practical, I take it on long trips so needs to be freeway friendly. that being said, I want the most radical cam that is streetable.

At this point, you are limited to just being able to make a lot of small changes and only getting small returns having to stay within certain parameters for street driving. Going too much larger with the cam could also require you to purchase a stall converter for instance. All of these things are just part of the puzzle, but not many are left that will keep you inside these guidelines without making daily driving suffer if they are even concerns for you. It may be time to do a cost to gain ratio calculation and see if the costs to gain what little may be left and still not sacrifice your driving needs are is acceptable. First, you may ask how much more of a gain are you expecting? And can that gain be achieved at an acceptable cost. You may only be able to net another 20 HP from where you are now, but if its going to be at the cost of another cam and lifter set and the cost of having to tear the head down and port it and install lumps at $500-$600 dollars for the package or more, is it worth it?

On the "dual weber"... do you mean TWO weber 32/36 carbs, or just one (which in itself is a dual)? If just one, then you need a bigger carb. One 32/36 is for a 4-cylinder engine.

Offenhauser doesn't make an intake for a "single" carb 32/36 Weber, so it would be for a twin 32/36 carb setup.

You could always go like me and put a 4-71 blower on it and make a new engine cover.

I agree, you've done all the easy & obvious stuff, what remains is far more labor intensive and expensive for much lower return in power per dollar spent. More cam will certainly add power, but low speed flexibility and "manners" in traffic will suffer. A "looser" converter will help there but $$.
Depending on your budget, fabrication skill, favors you can call in, etc. forced induction is the logical choice.
The Roots (4-71 Eaton etc.) are traditional, the Eaton is cheaper (used) but they make a large package.
A centrifugal (ProCharger, Torqstorm) is easier to mount alongside, drives off another belt.


A turbo is a lot of plumbing including the oil system, but the turbo itself can be cheap ($500).

$600 for 20 h.p. doesn't seem practical but nothing else has been either! stall converter was expected, so not a deal breaker. current cam is too mild, but never having a 292 before, nothing to compare it to. I have done the big cam, lower gears and run at 3500 rpm's to stay in the power, and was happier with 224 or 230 cams in v-8's. I have had comp cams 268 (218 @ 50) in a 250 and in a small block and in both cases wanted more. using ONLY that as a guideline, I can deal with 230. has anyone here ran that in a 292 that can comment?

dual carbs, with adapters and offy intake. not sure how much a better intake would help but space is at a premium. 10 h.p. at redline isn't worth it, 20 at cruising rpm and I will make it fit! biggest fear on cam is losing power where I need it to gain on the top, don't need bragging rights on the dyno, just leaving the red light. turbo or blower is past my skill level so a HUGE learning curve for tuning, kinda goes against my original goal of a simple carbed straight 6. avoided e.f.i. to stay simple and period correct. a modern engine would of been more practical and logical, I am way beyond that!

You should start by looking at the cam recommendations for operating range. The Comp 270H (224@.050)says it's range is 1800-5800 RPM, and suggests a 2000+RPM converter. The Comp 280H(230@.050)cams range is 2000-6000 RPM, and suggests a 2500+RPM converter. But converter companies suggest to select a converter that is at an RPM lower than your engines RPM at 65 MPH. So these suggestions may help narrow down the choices you will need to make.

comp cams no longer has the 270 listed and their 280 now claims 1500-5500 in a 230/250. marketing? 'if' accurate, that is ideal. would even be milder in a 292! howards has a 223 and claims 2000-5000 also requiring 2500 stall. the cam I had in my 250 was comp cams 268. was inquiring about 292 options and was told they are custom order only but had one 219 @ 50 and 526 lift that they got stuck with, discounted if interested. it accidentally fell into the 250 when I was swapping the head and can say without any doubt that it was not over cammed. the real question is how much more! brand or supplier is secondary but here are a few summit cams

I've been looking at camshaft profiles lately as well and I agree there seems to be a big jump in duration (at .050) between a "powerband" ending @ 5500 rpm or less and a "powerband" ending @ 6000 rpm or more. This seems to be "generally" true for most cam companies. example:

Crane's H-272-2 = powerband 1800-5500rpm = dur at .050 (216/228), 112 LSA
vs
Crane's H-234/3250-2-6 = powerband 3000-6000 = dur at .050 (234/244), 106 LSA

seems to me there's some room between those two profiles for a nice design.

howards seams to have more choices. what is confusing is similar cams from different manufacturers don't advertise similar powerbands. comp cams 230 1500-5500 but cranes much smaller 216 is 1800-5500? it even has a wider lsa! it has been beat into my head for 30 years not to over cam, but only did it once. the sales reps. all push the smaller ones and one even read word for word what I was reading on their site. more interested in hearing pros and cons from people that have ran different cams in a straight 6.

As for a cam, call Schneider cams in San diego. They have been in business for years and can grind cams for our inline motors. They did my last three cams and their recommendations ended up right on the money. Lump port the head. Its a project you can do yourself at home. The 32/36 Holley/weber Ford Pinto progressive 2 bbl, as a pair, is too small for a 292, particularly if you are using adapters.

I ran those carbs for years on my 235 motors and they were the cat's tail. Weiand 2 X 1, adapters, 74 Ford Pinto versions. Good runners, not too big, reliable. Put the same set up on my 261 (which had more compression, more cam, other stuff) and they ran just fine, but you could tell there was more. Switched to a Clifford 2 X 2 with weber 38/38 really woke the motor up. Not a cheap set up by any means but it is what it is. So I think you have a couple of things to tinker with, cam, head work that you can do in the basement (I did), and maybe some larger carbs in the future. I also think you are a little light in the rear gear department.

looked at cliffords dual 38/38 last year and cheaped out at last minute. already had the intake and weber/carter 32/32's so just bought true weber 32/36's. mostly for lack of available jets and linkage issues(long story). 'some' improvement on power/performance and fixed all my other issues. was concerned 38's would be too much, they are syncronise and 32/36 are progressive. I can upgrade down the road as I believe the adapters and the intake itself are less than desirable for performance. could use a little more gear. have a 12 bolt posi with 410's but was too low. 3.55's would be ideal but that requires a different carrier so likely end up with 3.73's. I am sure I can handle the lumps but would rather have a pro go threw them, porting, cc and mill and verify all else is good.

The Weber carters are smaller then the holly Weber 32/36. They are entirely too small for a 292. The 32/36s are also small, not as small as the carters, but will work. The 38/38s will not really work all that well with adaptors on a 2x1 Intake. I have rpthe 38/38s on an old style 261 motor and they run great so no problem with a 292. Let me encourage you to reconsider the Clifford set up. The manifold is cast with an internal heat chamber so no plates to leak or any mess like that.

And yes, you can handle the lump port yourself but if you want someone to install them, try member tom Lowe. He makes lumps and does installs and other head work. Use someone who is familiar with hopping up these motors. You will be heads and hands ahead in the long run.

it isn't so much the lumps, but more knowing porting is done right and rest of head is 100%. have had concerns from the day I bolted it on. while tuning, I noticed vacuum flutters 18-20 at idle. valve or guide? bar stool builders all say high lift cams do that, multi carbs do that etc. etc. just want a pro to check it out before I start throwing money in other directions. the Clifford is pricy but I can get a few bucks back from the current set up. still think it can take more cam but hesitant until I here what others are using. tom would be my first choice on head work if he is interested.

Yes, you have to be careful with the cam with regard to the automatic transmission. That’s why you want to speak with someone who knows what they are doing. Call Schneider. Don’t try to guess looking at a catelogue or talking to an order taker who is looking at a catelogue. 3:55 gears are a really good gear for all around use, at least I think so.

As the cam timing goes up (especially overlap, LSA & intake closing) the converter stall speed needed for easy traffic, prevent a stall on hard braking, etc. use goes up. Remember this may require additional ATF cooling capacity.
Unfortunately, more cam also lowers the stall speed with any given converter, so the cam choice has to be made first. Beware of "3,000 RPM stall" converters for PG, TH350, 400 etc.: these are rated with a 350" V8 engine, your stall speed will be lower.

don't completely understand 'cam timing'. I do understand long duration cams need higher rpm and lsa can broaden or narrow power curve but my knowledge ends there, maybe sooner! this van is the ONLY vehicle with an auto that I swapped cams in. also the only inline that I took this far. had a th350 behind the 250 and was o.k. with the 218 @ 50 cam but a 2500 stall really woke it up, 2 monthes later the tranny was toast! have a 200 4r now and relize a higher stall converter would be needed with a longer duration cam but prefer to stay closer to stock, maybe a few hundred over but not 3k rpm. biggest fear on cam is getting so big that I lose low end torque and need too low of a gear and too high of a stall. that fear and a good sales pitch is how I ended up with the cam I have!

called them, they are recommending 230 @ 50, 525 lift and 108 lsa. he first suggested 218 but when I told him I had that in a 250 and was happy, he said the 230 would be similar in the 292. he spent some time explaining the effects of different options and how it related to this particular motor. when we settled on this grind, he NEVER asked, let alone pushed the sale. just stated they keep it on file for 30 days.

Its why I like them so much. He has made three recommendations to me and they have all been spot on. The cam in the 261 is hands down the best performing cam I have had in these early motors. He spent some time with me on the phone and I appreciated the effort. Now, go order your cam, get your head to Tom Lowe for a look see and a lump install. Bite the bullet like I did and get the Clifford intake and dual 38s. Get some 3:55s in the rear. Wait until you see how much fun that motor is!

money tree doesn't bear much fruit in the winter so intake and 38's will have to wait. if tom doesn't pop in here in the next few days, I'll give him a call and even though 99% sure on cam, waiting a week or two doesn't matter and still waiting for that one member to post that they ran xxx cam in their similar build and love it!

I understand how the money tree grows lol. You may very well get a few who say I have xxx cam and love it. You, however, got advice from an expert, the actual cam grinder. Have fun with the build. Ought to be a pretty good runner!

lumps and cam is about all I can swing before spring. then time becomes my issue. might have to wait for fall to install the Clifford intake but you never know.