Hi everybody, I'm getting a 92 RS with a throttle-body 305. It's got a 160,000 miles on it, so I want to rebuild it soon. I would like to maybe have it bored out to a 350, but I'm not sure yet. What is a good estimate of how much this will cost if it's done by a good shop? I would like to do it myself but I don't want to risk messing up the engine. If you guys could give me an estimate for a basic rebuild and an estimate for making it a 350, that would be great. Thanks.

 

cant make a 350 out of a 305....

if you want to swap in a 350 cheaply, i would suggest something like the 350 HO engine, which all of your 305 enigne parts would bolt up to.

or you could build a 350, with a new induction setup (since TBI isnt really good), all new exhaust, etc. but remember going fast isnt cheap, and you get what you pay for.

Welcome to the boards

 

I have a 92 RS also with about that many miles on it with the 305 TBI.My plan is to swap out the 305 for a 350 and retain the original TBI.For this to work Ive read from a couple different mags you have to custom calibrate your computer ,swap out to larger injectors.Ive also read you can swap a computer from a gm truck with a 350 and TBI to your car and this can work.I think this would offer the most bang for the buck.

 

You can bore a 305 .30 over so it would be a 350, and then replace the pistons, rings, etc... I think that would be the easiest way to go, but I'm not positive. I just need estimates from people that have done it so I know how much I need.

 

a 305 +.030 is a 310 not a 350, not even close to a 350. i'm building a 408 right now and am trying very hard to keep cost down without cutting cornors and i'd guess i have around 2800 in parts and machine work. parts all pretty much cost the same reguardless of what the displacement is. look in jegs catalog and you'll get a pretty good idea of what to expect to spend.

 

Correct. Just like the old saying goes, "how fast do you wanna spend?"

 

Ede
I'm in the process of doing the same thing but the cost keep rising, however the end product will be worth it. Take a Look:
SBC 408 PARTS and PRICES
MANUFACTURE DESCRPT PART# PRICE
AFR Heads 195cc AFR-1035 $1370.00
ARPMain Studs ARP-234-5501 $51.95
ARP Head Bolts ARP-134-3601$49.95
Oil Pump Stud ARP-230-7002 $6.50
Oil Pump Shaft ARP-134-7901 $13.95
Fuel Pump Pushrod
ARP-134-8701 $ 14.95
ARP Cam Bolt ARP-134-1001 $3.95
CLEVITE
Main Bearing MS1038P $27.00
Rod Bearing 8-CB663P $27.00
CLOYES True Roller Timing Chain CLO-9-3100 $60.09
CRANE Energizer Roller Rocker CRN-11744-16 $132.50
EAGLE H-Beam Rods CRS6000B3D $335.09
EDELBROCK Elite Air Cleaner EDL-4207 $49.95
ELGIN Solid Lifters VT1992-16 $45.00
FEDERAL MOGUL Cam Bearings 1235M $19.00
FEL-PRO Head Gasket FPP-1014
(2x) $63.90
Intake Gasket FPP-1205 $13.95
Rear Main Seal Align Bored
FPP-2909 $18.99
K & N Air Filter KNN-E-1690 $43.95

LUNATI Flat Tappet Mechanical LUN-280/284F10 $183.71

MILODON
Oil Pump Pick-Up Screen
MIL-18311 $34.95
Milodon Street/Strip Oil Pans MIL-30900 $123.49
Diamond Stripper Windage Tray MIL-32250 $74.95
Lifter Valley Screen Kits
MIL-23150 $17.99
MELLING Oil Pump MEL-M55 $15.95
MOROSO Engine Magnet Kit MOR-22710 $15.99
MR. GASKET Oil Pump High Press
Spring MRG-26 $3.95
PIONEER Brass Freeze Plugs
SBC 400 $14.95
SCAT 9000 Internal Ballance Crank 400-3750-6000 $222.50
SUMMIT Fuel Pressure Guage SUM-800115 $15.35
WISECO Pro Tru Forged Pistons PT020H4 (0.040) $419.00

TOTAL COST $3,490.45

MACHINE SHOP WORK
K&P MACHINE Deck (.000) $150.00
Align Honed Mains $135.00
Tap Starter Bolt $30.00
Hone $60.00
Tap 3 Oil Holes $15.00
Install Deck Plugs $100.00

Mount Pistons to Rods $0.00
Balance Rotating Assembly $0.00
The two items above still needs to be done.

SUB TOTAL $490.00

TURNER MACHINE Bore w/ deck plates (.040) $120.00
Install Cam Bearings $25.00

SUB TOTAL $145.00

TOTAL $635.00

Still Need:
MSD Ignition
MSD-6AL Ignition Control MSD-6420 $195.95
MSD Ignition MSD Pro-Billet Distributors MSD-85551 $205.95
Holley 650 Mech Sec Carb HLY-0-4777C $325.95
TOTAL: $727.85

Where is my budget of building this engine for $3000.00

 

yep it adds up fast. i do my own tapping, valve grinding, cam bearing install, deck plug install,and freeze plug install among other things to cut cost. i'm also using stock heads. mine isn't a sbc, 402 +.030. i never did the math i'm just guessing it comes out to 408, might be 409 but chevy did that one already and i don't want to call it a 409.

 

What does the bore size come out to after the .030. Is it a 4.125 stock bore?

 

The stock bore is 4.125 +.030 over bore=4.155

 

bore is 4.130 checking it with a dial caliper. not really got started measureing or checking clearances yet.

 

That is what I thought. Is it a 3.75 stroke?

 

The stock bore is 4.125 +.030 over bore=4.155 and the stroke is
4.125X3.750=SBC400
4.155X3.750=SBC406
4.165X3.750=SBC409
4.155X3.8750=SBC420
4.155X4.000=SBC434

Now you can see how we make this Chey into different engines.
DTL504

 

I was going to put up the same chart with the different overbores but I needed to varify that I was right on the stroke.

 

from my manual stock bore is 4.126 and stroke is 3.76. a +.030 oversize would give me 4.156 bore. my manual isn't very clear and list 2 engines as 400s both with the same bore and stroke but the 396 comes out .001 under the the 400 based on the 396. guess i'll have to research this a bit more to find correct measurements before i put it together. i do know my piston clearance is right at .002.

 

That should be a 406 or 407 depending on ow you round.

 

well damn i hate to say i have a 406 and sound like it's a SBC, guess most people can tel lthe differance by looking that it isn't. i'll have to round up and call it a 407 or stick with 402 and forget the +.030 over bore.

 

Ok, ok, ok. How much does it cost for just a simple rebuild on a 305? No machining, just a rebuild. How much time will it take?

 

Well it comes out to 406.6 if I remember correctly so there is not big deal roudning up. Technically a 350 is 349.6 and we round that up to

Time depends on how busy the shop is and how good they are. They can have a motor taken out and apart in a day. A few hours for the rebuild and than another day to put it back together. It may be cheaper to pull it yourself if you have the tools and the know how. Also, it may be cheaper to buy a 350 shortblock and transfer everything over. That way you can kill two birds with one stone. More power and new motor. You will have to tune it though.

 

If that what you want why not get a 305 from Autozone with a warranty.....

 

Because he wants all of his bores to be the same size with the same pistons. Autozone motors are junk.

 

i think he'd end up with a junk engine either way. it's damn hard to rebuild one and not do any machine work. you could also save time and money not bothering to clean any parts.

 

If he dont want any machining, its obvious that he dont care about how round the cylinders are. Have you ever tries to rebuild a engine with no machining:
either way he goes its a no when situation. I would rather spend the money on a Autozone engine and have a warranty rather than rebuilt (if that what you call a rebuilt engine) 160,000 miles w/ No boring, honing, or decking. That not what I would call a rebuilt. to me its a shade tree mechanic with an engine that will not last....

 

yep i agree if you're going to not bother trying to do a good job i'd buy an engine from aurozone or similar outlet that had soem sort of warrenty.

 

You guys can forget about this post. I didn't get the 92. I got an 88 camaro instead. I'm just gonna upgrade the engine that's in it.