Motor Options (Need Opinions)

[pat123]

Well i am planning on rebuilding my engine. Its a stock 307 with a turbo 400 behind it. I am planning on putting an Edelbrock carb (650cfm, electrice choke) with a high rise Edelbrock manifold. I am also planning on put a double roller timing chain, cam (with a little more duration and lift), lifters, valves, and valve springs. I was wondering what your thoughts, addvice, options were? Also if i should change the heads while im at it? I know theirs going to be alot of different opinions but im interested in hearing all of them.

Pat

[thirdstreettito]

I'd say do it all and change your heads to some nice AFR aluminum ones. Lots of performance for your money and it wont seem like you are building a race engine because you can get street heads.

Check them out: http://www.airflowresearch.com/

And if you dont want to pay that much you can get Edelbrock Performer RPM heads which will give you good street performance throughout all RPMs.

Check them out: http://www.edelbrock.com/automotive_...t_sb_rpm.shtml

[LuckyHenriksen]

Aluminum heads would make a nice difference

[5150.4.67]

Look for some 305 heads with 1.94 valves. Or maybe some ZZ4/L98 aluminum heads that someone wants to unload 'cause they are upgrading to fastburn heads. They are out there, you just have to look. Or you could find a 350block, put your crank in it and turn it into a 327! Several possibilities. Gotta love sbc's.

[LuckyHenriksen]

Ooops didnt read that it was a 307, I thought it said 327. Personally, I wouldnt waste any money adding heads and what not to a 307. Im sure they are fine motors, but I would rather put the money into a 350 or stroker

[thirdstreettito]

You could also add more power by boring it .30 over to a 312 and adding forged aluminum pistons.

[pat123]

I could do alot of things depending on how muck i want to spend. I want to have the power but keep the best fuel econmoy that i can. I dont think its a waist of money spending it on a 307 but everyone has their own opinion. I was also wondering if anyone had these specs for my 307 heads ?
Chamber Size, Intake Port Size, Valve Sizes (in/ex)

Pat

[5150.4.67]

Yeah, If you want the best bang for the buck, a 350 is hard to beat. There are so many around that they are rather inexpensive....... but if you want to be different, build up what you have...... its only money.

[powerbench]

For a 307 , i'd just, imho , keep it simple , good dual plane , not a high rise maybe a 600 cfm carb and a bit more cam (good tow r/v) style cam....hei conversion and a set of headers.Pretty small cube motor to be putting a 650 on. Double roller for timing set..You probably don't want to start swapping heads unless you plan on doing a full rebuild ,or the motor has been built recently. If ya start building more compression ya usually see the rings go out pretty soon afterwards.I have to agree with everybody else, the money would probably be better spent on a 350 then..

[5150.4.67]

You would have to find the casting #'s of the heads. My guess is they 1.72/1.50 70 or 76cc chambers.

[pat123]

If i got the Numbers would you be able to id them?

[5150.4.67]

Yup. Or, you can try google as well.

[powerbench]

www.mortec.com

[heavy70]

you can surely have more power with a stock 350 than just building up the 307, but just add a 600cfm carb, dual plane intake and one of comps extreme energy cams preferably the 262 or smaller, and a set of long tube headers....

[racin69z]

Its cool to be different if thats why your sticking with the 307. But, you would without a doubt be money and power ahead going with a 350.

A 307 master rebuild kit is $129 more than a 350 kit. For $100-150 you can buy a rebuildable 350.

But like I said nothing wrong with being different. Just don't go in trying to save a buck.

[special-K]

The 307 is a small block Chevy motor.So,it is every bit as good as a 350,just smaller displacement.You don`t waste money by messing with it.Just,no matter what you do,you will have 43 less cubic inches than if you started with a 350.Why did people build 302s out of 327s with 283 cranks when there were bigger motors?Why would anyone want to make a motor smaller to race with?There`s alot to motor combinations to go with according to what the desired result desired.I`d sooner advise you to lose the TH40 and put a (cheaper to build) TH 350 in there for a quick 20 hp.
I rebuilt a 307 and here`s what I recall about it:
*4bbl manifold/Holley $450 cfm
*Headers
*RV cam
*1.94 heads(small cc)
*HEI w/weights(heavy) and springs(light)
It was built for a 4spd 3/4t 4wd worktruck,not for speed.The truck had 14.5" wide tires 37" tall w/4.57 gears.My goal was improved torque,better hiway mileage,and durability since I drove down the interstate to the suburbs,then in the mud once at the jobs,hauling weight the whole time.I got 15 mpg and ran along a bit better than a 350 and got way better mileage.I ended up putting it in a`70 1/2t 2wd when the work truck got a 350/TH350 swapped-in because the truck went to snow plow-only service and I wanted to try an automatic.The`70 had a stock 307 and when I put the one I built in,it was like night and day.I can only imagine if it was built for speed.Just the weight difference and less drivetrain to rotate made it a whole different motor.
I think the main reason the myth began about 307s being unworthy comes simply from the fact that 350s have been so plentiful for so long and the bigger inch mentality.There`s something special about a hot little motor.

[Tx Firefighter]

Rebuild it with decent flat top cast pistons (with 4 valve reliefs), Comp Cam High Energy 268 cam, Edelbrock Performer or Weiand Stealth manifold, 600 CFM vacuum secondary carb (I like Edelbrock carbs myself), HEI, and small tube headers.

You will be happy.

The increased compression will still run great on cheap pump gas, the cam will wake it up, and the intake, carb, and headers will keep the street manners intact.

Plus, if you ever upgrade to a bigger engine in the future, the intake, headers, and carb will still be appropriate.

[special-K]

^Oh yeah,forgot all about the flat tops.

[norwegianc10]

Originally Posted by special-K

Why did people build 302s out of 327s with 283 cranks when there were bigger motors?Why would anyone want to make a motor smaller to race with?

Due to the regulations in the Trans-Am racing series. When it comes to adding torque in an engine, there is no better way than adding displacement or to supercharge.

[LuckyHenriksen]

Ive never heard of a hot 307, only high winding 302's and 327's

[5150.4.67]

I too like little motors, why? To be different, yes I suppose. But there is something fun about being the underdog. I have a 305 making greater than 1hp/c.u. without much effort. You might even get better mileage.

[pat123]

Im going fo power and mileage. I also think its cool having something different. Everyone has a 350. I dont understan why get ride of the 400, my dad says their bullet proof?

im going to look for the head numbers tomorrow.

Thanks again for the imput still interested in everyones 2 cents
Pat

[bigsnookmaster]

It takes more horsepower to turn a turbo400, being that this motor won't make that much power considering the cubic inch, you would have more usable power with a turbo 350. If you had a bigger motor or raced the truck,over 400h.p. or so, a turbo 400 will last longer.My .02

[piecesparts]

Originally Posted by 5150.4.67

Look for some 305 heads with 1.94 valves. Or maybe some ZZ4/L98 aluminum heads that someone wants to unload 'cause they are upgrading to fastburn heads. They are out there, you just have to look. Or you could find a 350block, put your crank in it and turn it into a 327! Several possibilities. Gotta love sbc's.

The ZZ4/L98 heads are a great STREET head. They do have a lot of response up to the 4400 RPM mark, but then they plateau off at the spot. A good replacement for that head is a set of 96 and later Vortec heads. Aluminum lowers the weight, eliminates some heat issues that could give detonation at a highe compression ratio. The Vortec heads would require an intake manifold designed to support the different bolt pattern, but a steel set out of a Tahoe or truck will give a large HP boost for a decent price. The vortec will give you a power band that goes on up to 5800 RPMs and is worth it in overall performance.

I put Dart II heads on my 383 stroker motor and they gave me a good 30 HP boost over my stoke ones, but that was years ago and before the Vortec world started. It is all in the folow design of the heads and that is the largest change you can do to an engine for the money invested.

[kcjones]

Originally Posted by pat123

Im going fo power and mileage. I also think its cool having something different. Everyone has a 350. I dont understan why get ride of the 400, my dad says their bullet proof?

im going to look for the head numbers tomorrow.

Thanks again for the imput still interested in everyones 2 cents
Pat

TH400's are NOT bulletproof. I just spent $1200 having my case replaced and the inards freshened up because the 1-2 lockring tabs (part of the case) cracked. Here's the cool part: it was in front of a 280hp gm replacement motor the the PO put in, and the PO was a 55+ guy who used it to haul lumber to his job sites. I think he was a fence guy. No towing, no racing, no 120 degrees days, but I still ripped apart my case.

You can build a TH350 to be stronger than a TH400, and it'll cost you less and requires less hp to run. Definitely TH350 behind the 307 unless your TH400 is already in great shape.