May 1, 2017 Hotrod article featuring a Buick 350 rebuild

Steve, tune your combination using a set of long tubes and I bet you'd be knocking on the door of 12's.

 

Wait for the fast race in June. knock knock

 

Or if you were using the stock solid fan, you could remove it and use electric fans and it'd be just like strapping on a set of headers LOL.

Puts parasitic loss into perspective, and makes it well worth shaving off things that cut into power.

 

What month of HotRod is this article in print?
Just looked at June 2017 issue and this article was not there?

 

Written by Steve Magnante on May 1, 2017

Might take a couple more issues before they print it.

 

So his name is really pronounced Steve Lasagna?

 

I knew this had been posted before but couldn't find it. This along with Jim's level one build are true dyno proven builds. Having these posts and this particular post featuring a build using stock heads and stock valve size is encouraging for guys like me who are just doing a mild build or freshening up a low mile motor. 320 to 350 streetable hp is awesome. Lots of guys are shooting for that and these posts are helpful. Shouldn't they be in a sticky toward the top???

 

sure I made it a sticky

 

How much power was being left on the table with the 600 cfm carb? Your build uses a better cam and ported heads with bigger valves and made 25 more horsepower. Was some of that extra hp with your build due to the 750 qjet or was the extra power in the cam and head work? I'm honestly thinking about trying a smaller carb with my sp3 to help improve low speed throttle response and drivability. Everything I've read says the single plane will like a smaller carb and dual plane will like a bigger carb. I've also read that a heavy car with a highway gear will like the smaller carb. I spent about 2 hours last night reading different carb selection articles that have been published over the last 20 years. Once I get gearing, stall, and possibly a 200r4 I may try the 750 again.

 

Make sure its a double pumper whatever size carb you get for the SP3

 

Definitely. The 750 double pumper out performed my 650 Edelbrock everywhere except for the low speed drivability. I'm looking forward to trying a double pumper with smaller throttle bores. Gs Johnny and I have PMd a little and he likes the smaller carb idea too. I just don't have the compression and the stall and the gearing that you guys have. For $359 I can have a summit double pumper delivered to my door that may give me the drivability that I'm looking for. I don't think the issue is the sp3 intake. I think the problem is the annular boosters in my carburetor are set too high up in the throttle bore. So even though they're a high gain booster it's hard to get the velocity going through them with the overly large 750 throttle bores.

 

I think that now that the intake is no longer a restriction the smaller carb may work well. I’m convinced that the only reason the 350 in stock form likes a big carb is because of the intake restriction. Once the bottle neck is opened up by the intake a 650 CFM carb may work better. It’s not like it’s a high Hp combo after all. Once over 400 HP sure a larger carb may be needed. Notice how GS Johnny has been running a single plane intake for years and years way before TA came out with the SP-3.

I learned some of this from the 455 guys. A fellow was running an iron headed 455 with a 1000 CFM carb and once he went to TA heads he found a 850 CFM carb was a better match. I know it sounds counter intuitive.

 

Notice how GS Johnny has been running a single plane intake for years and years way before TA came outwith the SP-3. His small CFM preference is due to tray fact I’m sure. Also light vehicles with higher numerical gears respond differently than 4000 pound bricks. We did a bunch of dyno testing when I was having custom single plane intakes made abs sure they picked up peak HP with the 750 and 850 carbs but on the street or track I question if they would be the winner.

 

Theres very limited nice weather left here in iowa before winter hits. So I hope to have My cheap double pumper delivered and installed by the end of the week. If it runs like a turd I can send it back to summit and tell them to stick their cfm calculator where I dont ever want to see it again lol.

 

Good call. Also I’m not sure if you have any hood clearance room however I have seen a nice tall open spacer help with evening out fuel distribution issues.

 

I won’t have the cars out till spring for sure. Took this pic just now.

 

Nooooo. Not ready. It snowed here all weekend but it was around 37 degrees so nothing stuck. 50 is forecasted for later in the week...but I'm working till dark every night right now so testing my new carb during the day with good temps may not be an option.

 

Could be.
The SP3 intake is definitely not a restriction for sure.
The next bottle neck would be the heads.
A smaller than 850, 750 CFM carb would for sure increase throttle response on a combo that doesnt like the larger CFM carbs.
As far as "response" are we talking throttle response or eliminating the bog that occurs with non double pumper carbs on top of the SP3?

 

Small low speed throttle movements. Everytime I think I'm getting mine dialed in it seems to let me down. Not to mention it's just too rich. The smaller throttle bores on my edelbrock give me a completely different driving experience. And idle nicely around 12.9 afr. Horrible carb for performance though. Couldn't tune the bog out. The Quickfuel 750 likes 11.5 at idle and stinks and burns eyes. I got a kick out of this article.

https://www.badasscars.com/index.cf...ct_id=441/category_id=60/mode=prod/prd441.htm

 

when i started the 350 story, i wanted the oversized 2bbl that's made. i lost the bid on ebay.
i had the same guy build me a 650 that would carry me thru all iterations of the 350 build.
it was used on a t/a dp, my s/p, b&m 162 s/c and finally a 4-71 s/c. thats about 15yrs. never any problems.
going to the 6-71, decided to use an 850. tried dual quad 450's on it. so so. may try the 650 one more time.
somedays i think the 850 is too big. need to finish the d/q 455 intake. i think that will make things a lot better.

building a d/q tunnel ram for the 350. i think the mopar intake port locations are more precise than the wieands.
than a s/p for a 340. thats a tough nut to crack.
and then there is the twin v6 engine altered. lots of minor issues to resolve.