A while back i started a thread about wanting to build a tri power for my truck and i recived a lot of good info. I was told to build my truck as cheap as possible ( as its my first build ) and worry about details later ( great advice ). Now i have bought almost everything i need for my truck and have kept to a low budget, but the one detail i won't budge on is the engine and intake. The block is going to be a sbc 383 stroker with a tri power up top, as I'm just getting started I'm still learning and need some info please on the tri power build. I know their are loads of ways to build a tri power setup but could any body give a list / run down on all the parts i need to build please ? I going to source an intake and 3 stromberg 97 carbs to start with but just need to know what else ? Cheers
I am pretty sure that 3 x 97's won't feed a 383 ci engine! If I had no other choice I would probably run the large 2bbl Rochester to try and get enough air into the engine! Wayne
Thanks, that's the type of info i need...so if anyone one could recommend 3 carbs that will be ample ? Cheers.
The triple Rochester hotrod intake was available in this 55 catalog. It was made for the street and never considered a racing intake.
If you look, Edelbrock advertises the sbc 3x2 intake has a 5500 rpm performance rpm and that probably covers a smaller engine than a 383. This limit is likely due to airflow if not to fuel distribution problems in the manifold. I ran ran a set of 2G carbs for a 348 tri power on a 327 and the single Holley 4bbl and aluminum setup was better for performance and economy ,as long as I didn't blow a power valve.
My 2 cents... I am building one for a 283 I picked up most everything from speedway Manifold, Linkage, Rochester 2g conversion kit. Sometimes the kits go on sale or open box and you can get them cheap. Some guys make their own but I'm not good like that. I have been told not to waste my time on a 3x2 because 1 4 bbl would be better. I prefe the look and sound and in the city I can't really go fast anywhere
Is there any consideration to what is avalible in your area? Meaning, if you went with Rochesters would you have to order everything from overseas? I would think you would want to run whatever is more readly availible. IMO a 3 duece can be every bit as reliable and streetable as 4 barrel. And still make good power, it will just take more tuning.
Their isnt much here, and what their is costs a small fortune. So the costs i see over their with you guys I'm more then happy with...their cheap... So I'm collecting as many parts as i can to ship to England with my truck.
Really like the old adds...I'm not going to be racing it, i was advised by the guy doing the work on my truck that as i have a panel truck the extra power would be good for the weight of the truck.
You will need the smaller 2G's so the fuel inlet faces the outside of the carb. Then you will need a kit to modify the carb bases which either Speedway or Automotion can supply. I ran a set on a bone stock 283 and a 350. Both worked fine but be advised, the fuel in your end carbs get old unless you run wide open occasionally. I got my first set-up from www.hotrodcarbs.com.
So you can tell what displacement a small block Chevy is just by looking at the block? That's some talent you have there.
That would be a talent... A 383 could use a stock 400 balancer, but it looks pretty much the same as a stock 350 balancer... The 400 has counter weights in the back of the balancer .... Maybe if the engine was in laying out in parts.
You're telling us that you can tell the difference between a 350, 377, and a 383 just by looking at the block? Right. . . Go sell your snake skin oil somewhere else. I'm not buying it.
Prevailing wisdom says with Rochesters you must convert to the tripower bases on the outer carbs. Not necessarily true. I built a set that ran perfectly just by carefully fitting the butterflies to the bores to prevent vacuum leaks. Even left the power valves intact. Did plug idle circuits. There are so many "kits" for everything nowadays that rodders have forgotten how to do things themselves. Here's a pic:
I am wondering about the built motor also , I ran a 305 chevy out of a 1985 monte ss with a lopey cam and tri power .It was awsome with sound and in between shifts almost sounds like a blower winding down . Mine had the factory sbc 2 barrel carbs with the choke wired open (because it was egr therostate tube operated ). Later I found out the intake was angle milled for a special application and was making it impossible for me to seal it on my heads , I ended up buying a edelbrock tri power intake threw summit to replace the angle milled one .Something to keep in mind with used parts not every bodies application is going to be the same and sometimes totally different . Good luck and I would order the speedway motors catalog online it will help you a lot with what your are building .
After talking with someone on here who runs a 383 with a tri power i have descided to go with the 3 48's... This will give me more then enough to play with in my truck.
I just found this thread, and it seems you have made your decision; however, you might wish to at least consider a wee bit of history. Pontiac used three of the small Rochesters (which are significantly larger than the Stromberg 48's) in 1957 on the 347 and 1958 on the 370. These engines, while performance engines of the day, still were rated at 4600 RPM (well below the ability of the SBC). In 1959, when Pontiac's engine increased in size to 389, Pontiac changed from the three small Rochesters to a small center and two large ends). And as camshaft and other technology increased, allowed somewhat higher RPM this configuration was changed in 1966 to three of the large Rochesters on both the 389 and the 421. And when GM killed the Pontiac tripower in 1967, the Pontiac performance tuners were quite surprised when a stock 1967 Q-Jet ran the same 1/4 mile (on a 400) as their highly modified tripower from 1966 ran on the 400. Just a suggestion, but you might wish to look at the RPM you hope to run with your displacement and compare what was done by the factories. Jon.
Theirs a lot to read and take in for my first tri build. I know i don't want to be someone who just sits back and let's others do the work for me ( not that theirs anything wrong with this, as people's buisnesses are built by this) but I'm someone who needs to learn.
You don't need to spend the extra bucks for the throttle bodies on the 2GC build. But you do need to make sure the end carb plates are closed completely. Try to find a 3x2 set from a early Pontiac, Oldsmobile or three matching carbs (hard). You can use a 90 degree on the fuel outlet instead of trying to find the side outlet carbs.
I have been doing a lot more research and have been advised against the strombergs, especially running it on a 383. As stated below: "With 48's you are looking at only 480 CFM, BUT with big 94-2110's you are looking at 780 CFM. And 94's look every bit as good as the Strombergs" Does any body run a set up like this ? And do you have any pictures ?
I might as well throw in my opinion as well. If you simply must have a 3 deuce setup please go with the Rochester 2G series carbs. They work well and are readily available. The end units must have the bases altered for vacuum leaks and the idle circuits have to be plugged. If you want the power a 383 SBC is capable of you will want at least a 750 CFM 4 barrel on a single plane high rise manifold. 3 deuce setups won't flow enough air to feed the engine when it needs it the most.
2gc rochesters flow anywhere from 300-450 cfm depending on which carb, X 3 you will easily flow more than 750 at W O T.
So is above 750cfm an on target for a minimum for what a 383 needs ( just learning remember ) as the setup that was described to me last night would operate around 780cfm for the 94's...I'm not racing it , just want abit more fun on the road.
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