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Discussion Starter · #1 ·
Hi, I recently just bought a 1971 400 2 bolt main Small block chevy, its a complete virgin block. Sad part about the motor is that it has sat for about 3 years, and has taken a beating from kansas weather. Its froze, but the rust is not deep. A hone could easily take out the rust inside of the cylinders. The motor was tooken out of the truck due to a broken piston and just sat and sat. I recently just got a Job at a Nursing home, as a maintennaince worker, and Im kind of just pre planning the build completely. The motor will be rebuilt fairly stock, and Ill just do add ons until I reach my goal. I want the truck to be leaning towards the drag strip, yet still be fairly streetable.

Basic Plan- The vehicle that the motor will be placed in is a a 1986 s10, that weighs 3200lbs empty. Im looking to get around 450-500 horsepower at the motor and hopefully around 375-400 at the wheel. The tranny for the vehicle will be a TH 700r4 with a stall around 3000-4000, servoed out, and the differential gearing will be 4.10s.

Im thinking to hit around my goal, that this setup might be in the ballpark.
406 (.03 over 400), a 750 cfm Holley Double pumper. Im not sure of the intake, but Im thinking something around the 2500-6500 rpm range, Maybe a World Motown Intake that makes power from 2500-8500. A summit Capacitive Discharge Ignition Box with a rev limiter set at 6200 RPM. Dart Heads with 215cc Intake 64cc Chamber, 2.08 Intake, 1.8 exhaust. A Comp Cam, 2500-6500 .248/.248 Lift .525/.525. And a set of S10 shorty headers, with 1 1/2 inch primaries. Summit 1.6 Roller rockers. Stock bottom end for now, until I get enough money for all Forged. And a set of Drag radials, ttraction bars, just basic things to get some traction.

Do you think this could do high 13s on the 1/4 track ?. WIth 106octane, and a 100hp shot of NOS ?.

Anyt tips or advice is greatly aprreciated. Thanks :)
 

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i tryed the small block thing the only thing i didnt like was trying to change the plugs, u have to move the headers out of the way and the drivers side has the steering rod going in between the pipes. well anyway im swaping out the sb for a BB 396,use fenderwell headers,671 blower. oh your truck should have no problem probably should do 12's or 11's with the NOS
 

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Discussion Starter · #3 ·
Pre Planning Build For 400 Small block Chevy

Hmmm, sounds like its gonna be fun to change the plugs......EHhhhhh... Anyways I had a new question, I accidentally pretty much ruined the crank popping two frozen pistons out, the stud tore the hell out of the journals which I foudn out were all ready .020 under. So I looked in Summit, and found that I can get a 400 crank, for $170, external balance. Which uses the 5.565 rods. I noticed the harmonic balancer had a noticable machined groove, which I figured was the external balance, and heres my question, could I replace the crank with the summit crank, and not worry about having it balanced ?, someone from my neighborhood told me that I probably wouldnt have to worry about getting it balanced because they are all the same wieghts, and I figured Maybe...... But im not sure, I dont plan on spinning the motor(406) any over 6000RPM anyways.
 

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you need to get it rebalanced. Just look for a master rebuild kit with all your parts- you'll save money in the long run. There are a few other places that you can cut corners that won't hurt you too badly. If you can afford it going with 5.7" rods and forged pistons is a good idea, but I understand if money is too tight.
 

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smrat said:
i tryed the small block thing the only thing i didnt like was trying to change the plugs, u have to move the headers out of the way and the drivers side has the steering rod going in between the pipes. well anyway im swaping out the sb for a BB 396,use fenderwell headers,671 blower. oh your truck should have no problem probably should do 12's or 11's with the NOS
Please tell me this is a joke. Changing the plugs? Come on now it is not hard the change plugs on a SBC. Sounds like you had some very poorly designed headers if you had to remove them to change plugs.


This truck should run high 11's on motor. If you are not going to use forged parts skip the whole nitrous idea. Take that money and buy better rotating assembly parts, you can always add the nitrous later if you have a solid bottom end. If the crank is still good, use that but, buy better rods and pistons.
 

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Discussion Starter · #7 · (Edited)
Pre Planning Build For 400 Small block Chevy

Yeah, Ive never put a small block into a S10, but Im betting that it would be a little difficult to change the plugs, without fenderwells, Id imagine it would be a little easy... So you think this build could run high 11s on the quarter ? Wow, that was better then I was planning, would stepping up the stall help with the time ?, or would I risk traction loss, Which brings me to another good question, How do you get "decent" or adequate traction in a v8 s10 that has globs of horsepower ? I mean the little 6 banger could tear it loose all over asphault just because theres no weight.

????

Actually, I have an Idea to improve the time, what about, Steppin up my power band from 2500 to 3000Rpm, using the dart heads, with the 230cc intake 64 cc chamber, 4.56 gears, a 4000 stall ?
Do you think this setup would improve my time maybe to lower 11s high 10s ?, Im in highschool, and I want to make the truck faily quite, and drag the other kids with the supposive so "******" stangs, vettes, and camoro's, Would this setup be faily close to 500 hp ?, what is some improvements to get to that goal ? I used a calculator and with the 700rh and even with 4.56s it only wraps around 2600rpm at 65, I compared this to my moms Dodge avenger, and at 65 shes already at 2400Rpm, so I think I will use even a higher gear ratio and settle with the 4.56s.
??? Could someone run a desktop Dyno for me ?
Thank you
 

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Had to add CORVETTE and change "are" to are'NT

396flyby said:
Hi, I recently just bought a 1971 400 2 bolt main Small block chevy, its a complete virgin block. Sad part about the motor is that it has sat for about 3 years, and has taken a beating from kansas weather. Its froze, but the rust is not deep. A hone could easily take out the rust inside of the cylinders. The motor was tooken out of the truck due to a broken piston and just sat and sat. I recently just got a Job at a Nursing home, as a maintennaince worker, and Im kind of just pre planning the build completely. The motor will be rebuilt fairly stock, and Ill just do add ons until I reach my goal. I want the truck to be leaning towards the drag strip, yet still be fairly streetable.

Basic Plan- The vehicle that the motor will be placed in is a a 1986 s10, that weighs 3200lbs empty. Im looking to get around 450-500 horsepower at the motor and hopefully around 375-400 at the wheel. The tranny for the vehicle will be a TH 700r4 with a stall around 3000-4000, servoed out, and the differential gearing will be 4.10s.

Im thinking to hit around my goal, that this setup might be in the ballpark.
406 (.03 over 400), a 750 cfm Holley Double pumper. Im not sure of the intake, but Im thinking something around the 2500-6500 rpm range, Maybe a World Motown Intake that makes power from 2500-8500. A summit Capacitive Discharge Ignition Box with a rev limiter set at 6200 RPM. Dart Heads with 215cc Intake 64cc Chamber, 2.08 Intake, 1.8 exhaust. A Comp Cam, 2500-6500 .248/.248 Lift .525/.525. And a set of S10 shorty headers, with 1 1/2 inch primaries. Summit 1.6 Roller rockers. Stock bottom end for now, until I get enough money for all Forged. And a set of Drag radials, ttraction bars, just basic things to get some traction.

Do you think this could do high 13s on the 1/4 track ?. WIth 106octane, and a 100hp shot of NOS ?.

Anyt tips or advice is greatly aprreciated. Thanks :)
This is a very common and successful swap. You shouldn't have problems with headers, use Sanderson Shorties for this swap, they keep everything inside the engine room. Spark plug changes are tight as are re-torquing header bolts. The plug change problem is simply solved with using the shortest insulator plugs you can find like Accel header plugs, Autolites, or Nippon Denso's that fit the SBC work fine. Some wrenches choices make plug changes simple, most come easily with a conventional spark-plug socket turned either with a handle or an open end wrench. Some may be easily accessed with a product called O Ratchet. These let the insulator pass thru the tool which gives you plenty of working space. When putting the headers on look and think about fastener access after it's all bolted together, use either header bolts with the small 12 point head or Allen headed bolts as is appropriate to getting a wrench on them when the whole affair is installed in the chassis. Do these things and your tune up tasks will be simple. I also suggest you plug the oil pressure sender on the back of the block and tap off one of the drilled and plugged passages by the oil filter as you will find that when installed the top of the block backside tap isn't accessible. You will want a modern small diameter starter, this makes replacing the starter without unbolting and raising the engine possible.

Cooling these things is a PIA, forget the fancy radiators and never consider a 4.3 V6 unit. Get a 1970's era Malibu brass/copper unit for the big block motors with A/C. These can be fitted on the stock GM rubber bottom rails by moving them out-board a little. The top can be secured with the upper rubbers rotated around the front with the truck's radiator frame and the radiator's frame drilled for a pair of 1/4 inch machine screws and nylock nuts. The CORVETTE aluminum radiator mike Knell suggests also works well.

If you use a long water pump there's only space for a front mounted electric fan (s) which are'NT too effective. A factory fan will just fit on the pump hub and clear the radiator, but does not have space for a thermo cut out. If you convert the engine to a short water pump, you gain enough space for an OEM thermo-fan and stubby shroud, this does a lot for extended idle and low speed cooling

Get these two books and follow the recipe plus my notes and you're swap will be fine.

Chevrolet S-10 Truck
V-8 Conversion Manual
http://www.jagsthatrun.com/Pages/Chevrolet_S-10_V-8.html

Chevrolet TPI & TBI
V8 Engine Swapping
http://www.jagsthatrun.com/Pages/Chevrolet_TPI_TBI_V-8.html



Bogie
 

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Discussion Starter · #10 ·
Pre Planning Build For 400 Small block Chevy

Oh, my mistake, I dot know what year exactly, but you are right, its 1974 or later. Does anyone think this setup would be decent for my goals ? Horsepower ?.



Thanks
 

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396flyby said:
Does anyone have an answer ???

Thanks
400 to 450 horse from a 400 isn't hard to do and the 2 bolt caps will put up with it. 500 hundred is getting to some serious cam, compression, head, intake and exhaust design. This is the upper end of reliability of a good 400, 2 bolt block. The block can be modified to a 4 bolt and this is considered by many to be stronger than the factory 4 bolt. There are, also, girdles available which tie all the caps together, this adds a lot of rigidity to the main cap structure to help keep them in alignment and spread the loads seen by any one cap into all of them. This puts the engine well into being able to handle 5 to 7 hundred horsepower which is about the limit the block itself can put up with before you just pull the bearing webs out. I prefer to internally balance high output 400s, this is expensive but goes a long way to improving longevity when taking a lot of power out. You need to consider that 450-500 HP is also on the top end of the cast iron crank and short rods. At this power level a cast steel crank and 5.7 inch rods make a much more survivable bottom end. Getting above 500 HP one needs to look at a forged crank.

A 700R4 is not up to this, to feed 450 -500 horses will require a race prepped rebuild. This transmission has a really deep low, that combined with a 4.10 rear will be tire spin crazy. This is why so many guys look to the 200R4 for a competition transmission as it's low is not so deep. But it really takes building those transmissions with some stout as stock there certainly not up to a V8.


Bogie
 

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I would forget the Sanderson headers, Hedman makes a set with 1 5/8" primaries that are long tubes, and fit all inside the chassis. If you really want a huge amount of info about the V8 S10 swap that will keep you reading for weeks, check out v8s10.org , ;) :cool:
 

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PRO 48 fleetline said:
Might want to check your engine year all 400's from 1970 -1973 where 4 bolts
I had a '71 block with 2-bolt mains. The caps looked odd...they didn't come straight down like typical 2-bolt caps...more like big-block 2-bolt caps (like the one at the back of this picture).

That was the only early 2-bolt I had. I had two other 4-bolt 400's, and one later model 2-bolt, which had the typical "straight" main caps.

And for 396flyby, I had a '67 Nova with a 406, "462"-camelbacks(un-ported), 4779 Hollley DP (out-of-the-box jets...untouched), Performer RPM, smaller cam than yours, Muncie (and eventually a powerglide), 4.11-posi, 28-in. slicks, that put the car in the high-11's. Shouldn't be that hard to get 12's or 11's, so long as you can get the tires to bite. Your 1-1/2 primaries on the headers are a little small though.
 
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