Another 348 saved

[chase]

Hey fellas. Been lurking around this sight for awhile gathering info. I just finished my 348 build and had it on the dyno yesterday. A little back story, it's a '59 250 hp series out of my Moms old Impala. It had never been apart and was tired. Thought about the whole 434 stroker w/Edelbrock heads, yada yada yada but went with stock heads, stock crank, and single 4 barrel and was quite surprised. Here are the numbers; Torque peaked at 4200 w/385 and HP peaked at 5500 w/372. Very smooth curve. Torque at 3400 was 351. Idles sweet at around 800 rpm. Temp never went above 160 and oil pressure hovered around 70 psi. Not sure if this is good or what. I was pleased but wasn't sure what to expect. Any comments would be appreciated.

 

[Obnxs1]

Nice numbers. I'm assuming you must've put the Eddy intake on it as well?

 

[Dick MacKenzie]

Sounds good to me!!!

 

[Don Jacks]

Nice,which cam did you use,and are those numbers using headers,or manifolds?Welcome to the group.

 

[61belairbubbletop]

Welcome !
Sounds like you'll have a good running & very dependable engine, to me.

 

[skipxt4]

Those, Are Great numbers.

 

[Jim Sullivan]

Welcome to this great site Chase. Sounds like some really good numbers out of your 348. It would be nice to hear the build specs. How about some pictures also?

 

[63 dream'n]

Congratulations...... that's a pretty stout little motor ......best thing about it ...........it's a W

 

[chase]

Thanks for the comments. I went into this about 8 months ago and was hoping for around 400 hp and 425 torque but that was before I thought about streetability. Anyway, to answer some of your questions here are the basics of the motor. bored .030, align honed, decked, all galleys and lifter bores chamfered. Stock crank polished with Scat rods w/ARP bolts. Max lightened JE pistons (9.5:1). Sealed Power main bearings, Durabond cam bearings. Melling big block oil pump. Crane Retrofit hyd roller 558/574, duration @ .050 224/230. Lunati 5/16 .080 wall push rods. Howards hydraulic roller lifters. Stock heads (ARP head bolts) Ferrea 5000 2.09 intake valves, Ferrea 5000 1.75 exhaust valves, comp springs, Scorpion roller rocker arms (1:72) Edelbrock performer RPM intake, Holley 650 carb, MSD Ready To Run dissy (34 degrees) w/ composite gear. Edlebrock water pump, Edelbrock fuel pump w/ bronze rod. Dougs Tri Y long tube headers. Cloyes true roller chain and gears. Everything match ported, polished and balanced. I'm sure I forgot something. Anyway, I'll put a picture on here this weekend. Still in a crate I made. Thanks again guys. Look forward to continuing my total build with you.

 

[Obnxs1]

Are your stock heads the 379s? I'm sure others with more knowledge than me will chime in, but those seem like awesome numbers considering that and stock crank.

I decided to go the 434 route with 817 heads, a FiTech system, Eddy intake and Doug's headers. In a couple months I'll be able to tell you how that works out.

 

[Don Jacks]

Chase,for a stock stroke 348 in a heavy[any x frame]car,I'd back that cam down about 6 degrees @.o50 .If the engine is already built,then use a fairly deep rear gear,as this cam won't really start going until about 27-280o rpm.This cam would like a 10.5 compression a lot better but it is what it is,and should meet or slightly exceed your expections,but you're gonna have to spin it up.If you are going to run an automatic trans behind it,you'll need a torque convertor with a 25-2800 stall speed.

 

[buildit]

I agree with Don, you need another full point of compression, or (easier to do) back off on the camshaft duration. The LAST thing you need is a big block oil pump with a small volume 348 pan, if that's what you have. The rest of the engine looks pretty good!

 

[chase]

OK, now I'm getting concerned. The heads are 379's. The motor is built and dyno ran. Are you suggesting I should swap out the cam? I have no knowledge on cams, I left that up to him. I trusted that he would do what was best for my wants. It was tuned on a few dyno sessions and this is what it liked. The builder suggested 3:55 gears with a 2200-2400 converter in a 700r4. I thought of using a 4 speed but was worried about sourcing parts to convert. If I were to go to a 4 speed would I be better off? With the oil pump concern, are you saying that the pump produces to much volume and will drain the pan before the oil is returned? If this is so, will a 409 pan fix this? My concerns are this. I went to this builder because many people in this area use him. He has people running engines in street cars from stock rebuilds up to 1500 hp and I have heard of no complaints. Anyway I suggested 10.5 compression and Melling HV55 small block pump. I also stated that it would be somewhat a daily driver, at least 2-3 times a week to work and what. I was there for the last dyno and I must say the thing ran good. Smooth steady curve from idle to 5500 rpm. Idles smooth at around 800 rpm, has a slight thump but nothing outrageous. Sounded surprisingly smooth. However I have nothing to compare it to. This is my first engine build and it is my only experience with a w-motor. Am I set up for failure? I have a lot of money tied up in this motor and my wife will not be happy if I have to undo what was done by a cam and oil pump swap!!!! Thanks for the inputs and suggestions. I just want a nice motor that I can enjoy once and awhile and don't have to worry about it blowing up or burning down..

 

[Don Jacks]

Chase ,you have a great selection of parts in that engine.I agree with buildit about the oil pump ,but a new 409[or they also list a 6qt.348 pan] pan from Show Cars will solve that potential problem.As to the gear,go 3.70,keep the 700r4.Get a convertor like came in a 96 Vette[2800 stall]and enjoy!

 

[boxerdog]

Chase, I have had no problems with std volume BBC pumps, but I don't ever use 348 small pans either. I think the pan swap is a good idea, and I think the rest of it will be OK, especially with a 700r4.

 

[chase]

Thanks guys. I will change the pan and look into the convertor stall speed. Maybe split the difference and look at a 2600. Need to do more research on this and rear gears (not sure on wheel/tire size diameter). Still looking at 4/5 speeds also. No hurry, gotta a few months. Just want to make sure I am OK with the motor as is.

 

[Ishiftem]

Changing a standard pump to a HV one will not pump the pan dry. This is an old myth that simply will not die. A given size orifice (think engine clearances) at a given psi will only flow a certain amount of fluid. It doesn't matter how big the pump is. If you had a standard little pump in an engine and it doesn't drain the pan at 50 psi, you could change it to a pump the size of a football field and at 50 psi it will not move one drop of oil more. The only way switching to a HV pump will empty a pan where a standard pump wouldn't is if you increase clearances, decrease oil viscosity, increased pressure, or restricted drain back.

 

[buildit]

When operating psi is higher it does increase volume a small amount, but mostly it is just extra wear on the distributor drive gear. The last two 348 cores I tore down had front rod bearing problems, and I always wondered if oil level was low, or if they had been run at higher rpm while the oil was cold (slow drainback to pan). The rear rod bearings were in good shape on these engines. I do run a standard volume BBC pump on my 527" engine, but all oil gallerys were enlarged to BBC sizes, and I use a 7 quart Milodon BBC pan.

 

[poison ivy]

Sounds like you have a nice motor, enjoy it as it is, get it n car. you can consider the advise from others,on your next build.

 

[Ishiftem]

I had a bbc hv and I'm switching to a standard volume with the high pressure spring. Like you said, less cam gear wear and no reason to heat up the oil bypassing the extra volume.

When operating psi is higher it does increase volume a small amount, but mostly it is just extra wear on the distributor drive gear. The last two 348 cores I tore down had front rod bearing problems, and I always wondered if oil level was low, or if they had been run at higher rpm while the oil was cold (slow drainback to pan). The rear rod bearings were in good shape on these engines. I do run a standard volume BBC pump on my 527" engine, but all oil gallerys were enlarged to BBC sizes, and I use a 7 quart Milodon BBC pan.[/QUOTE