jb78L-82

Excellent recommendation. I find it amusing that building a standard small block 350 to 350-400 Gross HP requires some kind of high science-it is pretty easy! Getting to 350-400 NET HP requires a little more thought and money but certainly not very hard.

billla

Why would the OP invest in old-skool heads when NEW Vortecs are cheaper than rebuilding a set of old factory heads, won't crack between the seats and have far better mid- and high-lift flow?

Same for the cam - it's a great cam and one of my favorite factory cams...but there are better out there if originality is not key.

MakoShark72

You will have to ask the experts on here (billa, 63mako, gkull, motorhead, ajrothm to name a few) but this setup may serve your purposes. I think I have everything here except the intake..

http://forums.corvetteforum.com/c3-p...brand-new.html

If you think it might work for you, call me...

694speed350

Think most folks use hp at the flywheel instead of rw horsepower the exception of tghe folks that show the rw on the roller dynos. That th400 automatic is a power waster to the rear wheels.

billla

It's a good setup - and a great price - but the 210 cc intake runners wouldn't be my choice for this particular top. The factory roller components wouldn't work on this early GEN I block.

billla

Have you ever personally built a GEN I SBC, or done a top (intake/heads/cam) on one? Just curious about your personal experience base

scottyp99

If you want to compare two engines, gross Horsepower at the flywheel with no accessories is really the only way to do it, it eliminates variables. That being said, the amount of horsepower at the rear wheels is what will decide how fast your car is. So it is really the most meaningful number. And the lowest number of just about any way of measuring horsepower, so maybe not as satisfying. It's tough to brag about your 250 rear wheel horsepower, even tho that much power at the rear wheels ain't nuthin' to sneeze at.It's also the easiest way to measure the horsepower, just drive your car up on the rollers, strap it down and let 'er rip! Net horsepower just seems like all it does is muddy the waters, so to speak.

Scott

jb78L-82

Cam and intakes on my own motors and worked with 2 friends who have done all 3 on their own cars!

billla

Thanks!

Easy Mike

He said he had a budget.

billla

Doesn't really answer my question regarding buying less performance for more money...but OK...

efather

What other small items, in addition to once of the kits did you mean would make a diff?

I am going to start looking and deciding in earnest now that I have rolling chassis. Plus I have another project car on the horizon and am working to get the front clip back on to start that part of the project etc.

7T1vette

Good acceleration boils down to "torque management". With 3.08 gears and a TH-400 tranny, that is difficult to do. If you go to a steeper set of gears (3.55 or 3.73), you sacrifice highway comfort....for you and for the engine.

The better alternative is to install an overdrive tranny and keep the 3.08 gears. The low gear ratio in the tranny will enhance the takeoff torque, and the 4 gear ranges will better balance the applied torque than a 3-speed tranny would do. And, with better torque management by the powertrain, you could sacrifice a bit of hardware on the engine end, thus save some buck$ there.

For a nice 'driver' car, keeping the stock intake manifold and Q-Jet [you give up nothing by keeping the Q-jet], you can keep the stock SB hood (again saving $$$ over the BB version).

Vortec (or decent aluminum) heads and a cam swap with either hydraulic or solid lifters, would complete your upgrade and probably maintain your budget. Remember, you have low compression pistons, so you can use heads with low volume chambers and end up with a 9.0 to 9.5 ratio and still be able to run well on pump gas.

scottyp99

We have gotten used to cars with overdrive transmissions. Not having the overdrive on an older car is pretty annoying on the highway.


Scott

63mako

With a stock bottom end, 3.08 gears and TH400 you are limited to the cam and power you can use. I would go with something like this:
Cam: http://www.summitracing.com/parts/HRS-CL113215-10/
Heads:http://www.summitracing.com/parts/DRT-127122/
Intake:http://www.summitracing.com/parts/EDL-2101/
Head gasket:http://www.summitracing.com/parts/FEL-1094/
You will need to recurve your distributor (need to do this anyway), Pushrods, Thrust button, Pushrod checker, intake gaskets and head bolts and maybe a few other Misc. parts. This combination should get you 350 to 400 HP with your headers in a combination that will work with your gearing and short block for around $2000 and drop about #75 in front end weight.

efather

I the intake manifold looks like an edelbrock already but I am not sure which one yet.

I was thinking of one of the edelbrock topend kits 2022 or 2098. if I went with a kit like this (or another brand), I assume that would alleviate of need to get the misc parts (gaskets for example). My concern with not going with full kit, is that I wont get the right combination or correct items over all and the work will be for not.

What in addition would I need to concider getting, I actually cracked the distributer when I was removing the engine (forgot to remove it). So I know I will replace it, and I thought would need to swap the carb as well. I had always planned to swap the headers so the factory ones wont be used, they look like they were pretty rusted badly.


Sorry for such basic questions. Am just trying to find the better option and create some sort of shopping list.

7T1vette

You cracked the distributor, or cracked the distributor cap?

63mako

I used your gearing, trans and cast crank bottom end to determine the choices I recommended. The top end kits are pretty generic "one size fits all" options Most are overcammed and they generally shoot for a HP rating rather than designing it for your existing parameters and needs. An L82 engine with a 3.70 rear gear and 4 speed would have totally different requirements for the top end kit than your L48 with a turbo 400 and 3.08 gearing yet the top end kit from a given manufacturer would be the same.
The list I posted gets you matched components with proper quench , compression and a modern roller cam with the correct DCR and operating range for your vehicle combination. I did the research to keep your pricing in budget and meet your power requirements within the limits your existing combination allows.
No sense in changing the carb if it works well now. No sense in buying a new intake if you already have one that fits your needs. If your cap is cracked it is no big deal. If your distributor is broken I would upgrade and dump the points. Either way it is not a bolt it in and go option. It has to be recurved.
I am trying to give you the "better option" and "create some sort of shopping list".
This will get you north of 350 useable HP under budget????

efather

the cap, i am not sure what I was thinking. lol

I am not sure if the carb works well or not. I have not driven it too much more than test drive (basic) and pull it into the garage for work. The engine was rebuilt at 80K, and that was back in '85 and it is 96K now.

I appreciate the feedback, I thought the pushrods had to be matched (as far as length)
also?

Ill have to research the "recurve the distributer" part, I am not sure what that term means.

A lot of learning as I go, which is part of the appeal and fun of this project.

billla

Regardless of the top kit chosen, you should expect to have to do some mechanic work to sort out throttle/trans linkages, fuel lines, vacuum lines, etc. You'll need to know how to drop a distributor in, and how to correctly set valve lash. Most of this is pretty straightforward, but it can be a bit frustrating and take some creative thinking sometimes

If available, it's always worth investing in a dyno tune any time a signficant change is made - it's worth adding the money to your budget.

You will need to check pushrod length - it's not difficult, and about 1/2 the time the stock length will work fine. I think the Edelbrock kits just suggest a pushrod that's .100 longer and call it good - but it's worth spending the time to get it right. Ideally, you'll also want to get some help checking how far down the pistons are in the bore to make your head gasket selection - usually it's around .020 or so on a stock engine...but since your engine has been rebuilt I certainly wouldn't guess as this could cause serious problems in many regards.

Here's the link to the excellent timing "sticky" on the forum that discusses getting the timing right:

http://forums.corvetteforum.com/c3-t...long-post.html

Sounds like the shortblock is sounds - which makes it a perfect candidate for a top.

I'm not a super big fan of the Edelbrock kits - the cams and heads (except for the E-Street heads) are unremarkable for the dollars spent. There are certainly many choices in heads that would allow you to keep your existing intake - which would simplify things and save $$$ - such as the Dart Iron Eagle or the World Products Torquer. The best place to spend money is on the heads. I wouldn't invest in a retrofit roller cam at this power level, but it's certainly a good choice if it's within the budget.