400-450hp 355 on a budget?
 

Just looking for someone to tell me if im crazy before i call my race engine shop for machine work and parts tomorrow and sound like i lost my mind. :crazy:
Im looking to build an honest 400-450 hp 355...or 357, depends on if the guy doing my machine work says my bores are good to go. I will be doing all the assembly work on her myself and already have it down to a bare block to save some buck there.
Looking on going with the weiand 177 blower on top of my 355 to help get me there. Blower kit i priced out at $2359 through summit but my builder is going to see what he can get it for. Carb to top off the blower is $580, its the 750cfm holley blower carb. I priced out a dished forged piston and ring kit at a 26cc dish for $720. I was checking out this cam and lifters for $225 http://www.summitracing.com/parts/CRN-113822/
Set of larger tube headers $160. Then i fig rod and main bearing around $40. Pricing everything through summit i had a cost of $4130. My builder said he would see what he can get me parts for if its any cheaper. Heads i have that are paid for are the 492 casting double humps. 64cc chambers and 26cc dish should plot me somewhere between 8:1-8.5:1 comp ratio right?

Final question do you think i can hit my hp mark with this setup and do you think im crazy for trying to do this motor for a budget with a max cap of $5500?

Re: 400-450hp 355 on a budget?
 

just sayin
plan on spending more than you think you budget

Re: 400-450hp 355 on a budget?
 

Yea im planning on it, obviously there is still oil pump, water pumps etc etc...i calculated roughly $4100 on parts through summit, my machinest/builder said when i find out what i want to do he will see if he can get stuff cheaper but then machine work on top of this. I really dont think i will be able to swing over $5500 on motor without sacrificing other stuff i wanted to do to the truck before spring. Am i crazy thinking i can pull off this set up for that price and do you guys think ill be in my hp range?

Re: 400-450hp 355 on a budget?
 

I know it all comes down to when i call the man tomorrow i was just looking to see if im still in the realm of reality.

Re: 400-450hp 355 on a budget?
 

A bit of advice. Years ago I had a builder with a good reputation build my old 406. It was over 10 months from the time I dropped off the short block until I picked it up ready to run on the dyno. I realized costs would be high but I felt I was prepared for a little over budget. In the end the cost was waaaay over budget. I had a heck of a strong engine after it was done but way over my estimated costs. MAKE YOURSELF A BUDGET AND STICK TO IT. I listened to and trusted him a little too much and his cost was actually not cheaper than the catalogs. Keep in mind builders and machinists have to make a living to, you just need to decide how much of it will be at your own expense.


Unless you are going racing do you really need the most expensive set of heads or the most expensive cam? Just food for thought from someone who has been down this road once.

Use your own head and invest your time to research what you need, and shop for your best prices.

This kit looks pretty good price wise and I've heard the quality is good to!

http://www.northernautoparts.com/Pro...ctModelId=1666

Re: 400-450hp 355 on a budget?
 

HP is 'over rated' This magic 400HP number is just like splitfire plugs and trickflow heads. It's been beat into our heads with every add in every car rag. FORGET the numbers and build for the most torque in the rpm range your looking to use. If I build you a 327 that makes 500normally aspirated horsepower on a single carb,,,,will you be happy???? NOT on the street because I'm going to built it to make this magic HP number around 7500 - 7800 rpm. Even if you use a 26" tire and 5.43 gears, you aren't going to be spinning 7500rpm anywhere between stoplights are you! A 500HP small block is going to make 75-100HP in the DRIVABLE range of street driving (1500-3800 typically)

Look, I know you said 400-450 was the goal, but the point is the same. High HP small blocks dictate high RPM!!!

Let's use the 6800RPM HP peak that is typical of a stout small block (400-700HP all peak around this same range of 6800-7200 on a real dyno)

If you use a TH350 or TH400, With a more typical 3.43 gear, and a 28" tire like you would find on a Camaro or sedan,, not on your truck, ..... but for example.

You are going to have to hold it in LOW gear to 65mph make use of that 6700rpm peak. And that does not even take into account optimum shift points for an after the shift RPM to make best use of power curve. Tell me how your going to use that on the street????????????

Easiest and most bang for the butt-o-meter on the street is cubic inches. If you want to keep your 4" bore,, cool. stroke it to a 383. Parts are cheap, and a 383 is as easy as falling off a log to make 1HP per cubic inch and MORE IMPORTANT,,, 400+ pound feet of torque in a DRIVABLE RPM range. 9.5:1 compression and pump fuel, Decent heads that flow (a MEASURED, not advertised) 240ish cfm, a hydraulic roller to get the reliability and valve action to make good power below 6500, and a dual plane intake will make enough power to shred any tire you put on the truck,, and if you ever get it to hook,,, you will shred drivelines, transmissions, U-joints.......

Seriously, FORGET THE horsepower wars.

Re: 400-450hp 355 on a budget?
 

I don't think you're crazy at all. It is definitely do-able for that price. Sounds like it will fun to drive as well. If you are buying a crank, you should definitely consider a 3.75" stroke and build a 383. "there's no replacement for displacement"..... Just know that all the little stuff adds up, (oil,plugs,water pump, t-stat, filters, gaskets, sealer, etc..) The list goes on and on. But $5500 should build a helluva motor.

Re: 400-450hp 355 on a budget?
 

To Marv's point, 400ftlbs of TQ at 5,252 is 400hp at that same RPM. TQ is the force that moves the object where HP is the amount of work the TQ will do over time.

Re: 400-450hp 355 on a budget?
 

I would agree, build a 383 ci engine and put that lil blower on it and you should have one helluva good street motor.

Re: 400-450hp 355 on a budget?
 

Im off the numbers train!! Everyone asks how much power I say let's go for a ride and you tell me. My motor might make 330-350 hp and probably the same torque but coupled with 28" tire 3.73 gears and 700's first gear it's a monster... Would I like more, Hell YEA but then it's a matter of how often you want to buy tires or other parts. If it was me flattop motor, 6" rods good heads/topend combo or do your research and have fun!
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Re: 400-450hp 355 on a budget?
 

I here the 383 + blower combo is actually pretty tricky to pull off between comp. ratio and getting a blower cam properly clarenced and considering the $2300 blower is consuming alot of my budget i think i best stick with the 355 idea haha. I do want drive ability and torque over hp though, just kinda set my goal to beat a buddy on the dyno. Did talk to my machinest/builder and he claims with me doing the tear down and assembly work i shall be plenty in my budget and hitting my hp goal! Ill have to give you guys an update with dyno numbers as she gets wrapped up.

Re: 400-450hp 355 on a budget?
 

So ur building a blown 355?
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Re: 400-450hp 355 on a budget?
 

That's the plan
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Re: 400-450hp 355 on a budget?
 

I think what Marv was saying is you can make your 400HP goal w/out the supercharger on a well built 383 that will be much more streetable than a 400hp blown 355...

He's got a lot of experience! :metal:

Re: 400-450hp 355 on a budget?
 

I vote 383 325-375 reliable hp and a broad flat torque curve across the board . Buy good pistons and add 150 shot when needed wanted .

Re: 400-450hp 355 on a budget?
 

400 is very easy with all the modern cams we have now. That little blower should add a bit of each.

Re: 400-450hp 355 on a budget?
 

I guess I'm crazy, my 355 is making around 425hp on pump gas without a blower and drove it as my daily driver for 5 years.:metal:

Re: 400-450hp 355 on a budget?
 

I'm running a 383 that puts out over 400 ft. lbs. of torque from 1500 rpm on and has over 500 hp.definately nice to have that low/mide range power and torque.it's a full roller motor and cost about $4600 from the oil pan to the air cleaners(tunnel ram/2 holley 390's)but I did alot of parts hunting and found several good deals on ebay and craigslist.

ken

Re: 400-450hp 355 on a budget?
 

So, just curious, why do most seem the have the thought that a blown 355 is going to be low on torque? I mean its not like a blower is just a hp adder, from what i understand they do more for torque than hp.

And happy thanksgiving to everyone here!

Re: 400-450hp 355 on a budget?
 

Pete,

Since HP is a function of TQ * RPM / 5252, any increase of torque directly increases HP. But here is the kicker. If you are looking at increases bellow 5252rpm, you will always see more TQ than HP, above 5252rpm, more HP than TQ. HP and TQ always cross at 5252rpm.

Example:

TQ - RPM - HP
300 500 --- 29
300 1000 - 57
300 1500 - 86
300 2000 114
300 2500 143
300 3000 171
300 3500 200
300 4000 228
300 4500 257
300 5000 286
300 5252 300
300 5500 314
300 6000 343
300 6500 371
300 7000 400
300 7500 428
300 8000 457

Re: 400-450hp 355 on a budget?
 

There is a lot of HP and TQ numbers being posted up here. Curious if any one has the dyno charts they can post?

I'm going to side step this and add my 2 cents. I'm a vivid fan of the 6" rod 400sbc. You will have street ability TQ and HP numbers that makes the other combo's humble.

Re: 400-450hp 355 on a budget?
 

http://www.carcraft.com/techarticles...d/viewall.html
I was just scoping out this article doing some more research. Looks pretty much what im looking to put together minus the vortec heads, heads probably wont be in my budget however that is working with a bone stock junk yard std bore 350 and a little 142 blower, between my .030 over and the larger 177 blower if i spool her up a little i think i may be able to hit similar numbers. But very excellent dyno chart to show the street-able torque a blower is capable of i think.

Re: 400-450hp 355 on a budget?
 

I mean by no means am i trying to show any dis respect to any of you guys by sticking to my guns on the blown 355 idea. Just seems like everybody and their uncle does a 383 at some point in their life. I want something that is going to be different around here when i take it to car shows and i think a little 177 blower hiding away under the hood will be pretty different, i haven't seen much of that around car shows here but i do see a handful of air cleaners with 383 on top of em.

Re: 400-450hp 355 on a budget?
 

Alot of their power is coming from those heads. They flow worlds above any other production iron head (excluding double humps) The larger blower will help, but heads are a big factor. The more air you can get in and out, the more power.

There is nothing wrong with a blown 355, and if thats whats in your budget, then do it. To me, a blower on a 355 would be cooler to look at than a n/a 383 any day.

Re: 400-450hp 355 on a budget?
 

So...when you say excluding double humps is that a good thing then that im working with the 1970 lt1 double humps?

Re: 400-450hp 355 on a budget?
 

They are good heads (apparently I overlooked that in your original post...lol), but vortecs are hard to beat. From what I've read the 492 heads flow about 210 cfm at .500" lift, and the Vortecs flow 240 cfm @ .500" lift.

Re: 400-450hp 355 on a budget?
 

alright...with vortec heads you will never get more than 400hp out of a motor.
When i worked for summit racing I built a true 400 hp 350 for $3,000 with all brand new parts. it dyno'd at 410hp and like 380 ft lbs.. I put this in my 78 shortbed with a th350 and 3.08 gears and got 14 mpg.
gm 260hp crate short block $1600
lunati bm2 cam/lifters $150
trick flow KD 23* heads $600
edelbrock rpm intake $ 160
demon 650 carb $ 300
1 inch 4 hole phenolic spacer $ 15
holley blue e fuel pump $100

granted the heads i got at employee cost @600 but that shows you what can be done for 3k. All while backing off the timing and running cheap gas for daily driving. adding a small weiand blower would probably made that a 450hp/450ft tq motor...

Re: 400-450hp 355 on a budget?
 

Which vortec heads exactly and what pistons/compression ratio?

Re: 400-450hp 355 on a budget?
 

I didnt use vortec heads.. i used aluminum trick flow heads with cnc chambers... the chambers were 64cc and on the factory crate pistons it upped the compression to 9:5-1. I also forgot the aluminum roller rockers that i used. The heads i got at employee pricing @600 for the pair because summit owns trick flow....cha ching!!!!

Re: 400-450hp 355 on a budget?
 

AMEN,, I always try to sit on my hands and try so hard to keep my mouth shut when I see "makes about" or "makes over" (not say anything about anyone here).

I apologize in advance for whatever feathers I may ruffle here but.........

the kid brought it up so,,, RE: those 'unfounded' claims...... inquiring minds want to know, SAYS WHO???

Desktop dyno is a joke, and to add... everyone inserts these lavish parameters when they don't know the 'real' answer. DDyno is foolishly optimistic anyways (it sells product so that's all they care about). So with pipe dreams thrown in they get a insanely inflated # to throw around the internet with the disclaimer of "about" or "more than" or my personal pet-peeve,,,, the same as some magazine build (but different ) and the article was nothing but a paid advertisement in the first place!!! . (and that is not pointing fingers at anyone,, just saying)
Programs like Performance Trends Engine Analyzer will give an honest estimate IF 100% factual and exacting data is input. Shaun has proved that over and over. But he doesn't GUESS at anything, and EA asks more questions than most, but experienced engine builders would know.


BUT,,, nothing is the 'real' answer except a true SuperFlo computerized engine dyno.

OK, sorry to those I offended,, and rant off

Re: 400-450hp 355 on a budget?
 

if you guys are trying to stay in a budget,why not go big block?? I have 1500 in my 454 setup and it has WAY more torque than any small block did...

Re: 400-450hp 355 on a budget?
 

I can usually guess pretty close to what a motor is gonna put out if i have all the specs laid out...its not rocket science.. however, i have been in the racing parts biz for years and raced even longer and cant count how many dyno sessions i have been to.

On my sbc build i listed, i based the combo off of a trick flow top end kit they used to offer. It was a 440hp kit if memory serves me right. I used a different cam that i knew wouldnt make as much hp but more torque and was guessing i would make 390-400 hp. I was pretty damn close but that was based off of a verified combo where i only changed 1 variable

Re: 400-450hp 355 on a budget?
 

I just figured it would be cheaper to build up the motor I had rather than completely starting over. Block should be going in for machine work Monday, I'll have to keep you all updated with progress and some dyno numbers when she is done
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Re: 400-450hp 355 on a budget?
 

I don't know where you got that info, but it is incorrect. Summit racing sells several naturally aspirated blueprint crate engines with vortec hads that have 405hp and 440 lb.ft.. So you're telling us that adding boost to a 400hp vortec headed engine is not going to increase the power???

I know this is off topic a little and I should probly just bite my tongue, but Vortec heads will absolutely make over 400hp n/a, and adding boost is only going to add power. I have seen a single turbo vortec headed 355 go 8.80s in a 4 dr chevelle. Pretty sure thats more than 400hp.

Sorry.

Re: 400-450hp 355 on a budget?
 

I believe guido is speaking normally aspirated, and I'd have to agree, but I should sit on my hands let him clarify that himself.

And I'd agree with it DEFINATELY in referencing the GM production vortec castings. In fact making 400 n/a with a L31 head warmed over.... well,,, Hell even the ZZ4 / Fastburn package with hot cam and everything McClaren could do short of a real port job only made 380ish on a 'REAL' dyno.
The aftermarket offers a vortec style head (such as the Edelbrock E-tec in 170 and 200cc version, as does a lot of others) that is well capable of closer to 500 n/a on a big inch small block.

Re: 400-450hp 355 on a budget?
 

I guess I read wrong. I thought the OP was asking about using a small blower.

either way it doesn't matter much and I should have just left it alone as the OP is not in need of a set of heads.

Re: 400-450hp 355 on a budget?
 

is the o/p set on that roots blower.. would a procharger be better?
I'd forget the hp # and build for a nice fat torque curve..
mag hp# are nice but at the end of the day you have to ask, while looking at the dyno sheet, just how much of the time will I spin the engine past 4000-4500 ?
remember these trucks are not lite.. torque is king baby..
with the right parts you should get 450+ ft lb at a nice low rpm with that blower set up right.. meaning set up for the rpm you plan on driving at..

Re: 400-450hp 355 on a budget?
 

I am asking about using a small blower. And i may be in the market for a set of heads. Are there any Good cheaper aluminum heads out there that dont cost an arm and a leg? Or even some good aftermarket iron heads? Id like to stay away from the vortec scene kind of, unless its my only option. I know when it comes to heads you get what ya pay for but are there any decent aluminum heads out there that will work better than my double hump without breaking the bank?

WAAF-yea i kind of an set on using a roots style blower, just kind of one of them things i always wanted to play with, i deff covered the turbo with my monster on my powerstroke and the roots blower is deff next on my list of what to play with. I thought the torque curve on the vortec headed magazine blower build was pretty nice. 455 ft lbs peak at 3800 rpm and 416 ft lbs at 2800 rpm, i didnt think that was too shabby.

Re: 400-450hp 355 on a budget?
 

From what I know a roots will make more TQ in the lower RPM compared to a centrifical blower. But I have no first hand experience. I believe the centrififal makes more boost the faster you spin it.

Patriot makes a decent upgraded cast head for a good price. It is machined so you can run either a Standard SBC intake or a Vortec. It also allows you to get some lift on the cam and they flow pretty decent. If memory serves they make this same head in alum for $400-500 more.

Re: 400-450hp 355 on a budget?
 

yea i started doing some research on heads and noticed patriot aluminum heads for their fair price, however i started looking up reviews and noticed just as many negatives on em as them pro comps on ebay. I dont know, right now im trying to fig out a way to fit some AFR's in the budget, but i dont think they will fit in haha. Either way, im going to send my old heads to the machine shop with the block and i guess the discussing of what we can or cant do will start there, i really cant afford to blow my budget at all, minus machine work the afr's fit the budget nice and snug, work is going a little deeper into winter than normal, by now its normally slowed right up so i may be able to expand the budget to $6000, but i dont want to push it.