choff

Hey guys just started building my 87 sport for 1/4 drag racing. I have a 355 sbc 4 bolt mains camel back heads with a little polishing. Hardly enough to make a difference I think. It has a comp cams xtreme energy hydraulic flat tappet with .519 intake .523 exhaust at 110 degrees. worst parts of the engine is I don't know the compression ratio and It has a edelbrock dual plane intake with a demon 625 cfm carb. I love the demon but might have to go bigger. The trans is a fti th400 stage 3 rmvb with a 3600 stall into a currently stock 10 bolt that I have no idea what direction to go with. I was thinking spool with 4.11 gears. Car is almost going to be strictly for racing but is full weight minus small things like heater box delete and removed rear seats. Has s&w bolt in subframe connector going in soon.

TTOP350

iTrader: (8)

You're going to hear this, "May want to swap heads to vortec".

choff

If Im switching heads I'm going to aluminum heads from brodix, afr, or edelbrock and going sinlge plane edelbrock victor jr.

Jacobaxeman

Will it do 12s right away? Probably not. After testing and tuning, getting to know the car, and the right set up all around, yes it will do 12s. Not always as easy as putting an engine in, a lot more to it.

Good luck looks like it's gonna be cool

MoJoe

iTrader: (5)

Camel hump heads - great in 1970. Much better designs are available.
Vortec - great bang for the buck. $600-ish new, or the better bargain shoppers can find used in the $100 range.
AFR, etc - If your budget ($1500+) allows aftermarket/aluminum, this definitely has a higher power potential.

Speed costs money. How fast are you willing to spend?

AlkyIROC

The 625 on a 350 street engine is fine but a little small for drag racing where you normally operate at WOT. A 750 would be a better option. Single plane manifold is good for the street and helps make low end torque even for the dragstrip but a single plane is a better "race only" option. Best stall speed depends on the actual cam grind. Too much stall can be just as bad as not enough. Without knowing the cam grind I can't recommend a stall speed.

I had some highly modified camel heads with big valves on a 383. It had a bigger camshaft and carb (850 CFM). TH350 with a 3800 stall. 3.27 gears in a BW 9 bolt.

Managed a very high 11 second pass before finally blowing up the engine. Cast aluminum pistons and stock 400 rod bolts don't like spinning to 7000 rpm

By today's standards, camel heads belong on period vehicles who want to keep everything close to what they originally had. There are much better heads out there. As already mentioned, Vortec heads are much better than the camel heads. DO NOT invest money into the camel heads. You can go and buy some iron Dart Sportsman heads which will come with larger valves, better springs, screw in rocker studs etc and flow better for less than what it would cost to upgrade the camel heads to do the same thing. In the late 60's and early 70's they didn't have the aftermarket selection that we have today so at the time, those were the best performance options for heads but not today.

Even using an offshore aluminum head is not an exotic option that it was 30 years ago. Prices of aluminum heads makes them very affordable for just about everyone.

Building a high HP engine for racing is only part of the whole package. The TH400 is a good option. It's stronger than a TH350 and has a much better gear ratio for racing than the 700R4.

Your 10 bolt diff is your weak link. Don't invest a lot of money into it since no matter what kind of improvements you do to it, there will still be a tiny ring and pinion in it. You can spend $1000 trying to make it better and that money can easily go towards a better aftermarket diff. Start saving for an upgrade. You have 3 options for an aftermarket direct bolt in diff. A 9", a 12 bolt and at Dana 60. There are no junkyard options unless you change the rear suspension to eliminate the torque arm system. Upgrading to an aftermarket diff is going to set you back at least $1500 and $3000 is more common. Price goes up depending on what options you use. A spool is much cheaper than a posi etc but you'll probably want to upgrade to disk brakes at the same time as a diff swap.

It's a track only car. Gut it. If it's not required for speed or safety, get rid of it. The same HP in a light car will go faster than in a heavy car.

Lastly, tires. Lightweight rims and slicks. You can make lots of power but if you can't get the power to the pavement, all you'll do is spin off the line.

fasteddi

iTrader: (2)

So that cam is like a xe284 or something in that area of 230-240 durration at .050?

I would definitly put different heads on before anything. Something that will flow more. 195 afrs or even dart or profilers would be awsome. I have some afrs I have yet to toss on but currently am running dart iron 200cc heads. Which are also for sale...lol

Everything needs to be matched up or you are missing out on potential.

I ran a performer rpm intake all this year which is a dual plain intake. It worked great for my set up. I do now have a victor jr but that's going on with the afr heads. I also have that performer rpm intake for sale. But if it's a race car only then single plain is the way to go, exapecially if you are running a 3500 stall or more. But if you have heads that only flow 200cfm or less don't expect to have 450hp or something as it just won't happen.

Here is my set up Iran this year, I know my engines bigger bit it gives you a idea. And I am completely changing all of it this winter hoping to run 10s. New heads cam intake rear end and converter.

385ci
eagle rotating assembly.
11.1:1 comp
dart 200 64cc heads.
performer rpm intake
Holley 750 carb proform main body
1.6 gold rockers
xe268 cam
run on 93 octane 34 degrees total timing
3500 stall
3.23 10 bolt rear
Best of a 11.62@114.8mph
Best 60 1.57
I do have alot of suspension mods race weight of 3380lbs. But it is still a street legal car full interior.

fasteddi

iTrader: (2)

Also I've ran a 10 bolt for years just recently buying a s60 strang I have yet to toss in as well. The 10 bolts are a roll of the dice. They don't make spools for them so it's either a locker or mini spool or lsd. I also have a nice locker I'm trying to get rid of if you are interested. But if you can save up.... a 9 inch or s60 is the way to go!

izcain

You can do junkyard on the rearends it just depends on how crafty you are and if you like welding and building something like that. Several people have gotten a ford 9 or gm 12 bolt and welded the brackets on and shortened the tubes and built something. Is it cost effective? maybe, a lot of times it is cheaper to buy the drop in unit over the long run.


My only advice is to try to get items that you can grow into. The th400 is a good item. Aside from the only negative of it being heavy you can always add things to it later to beef it up further.

If you keep your overkill goggles on all the time when dealing with things you will have a dependable car haha

A quick car is not always the one with the most hp. It is the one where everything is working with one another and matched well.

The most important thing of all, Have fun!

Right out of the gate a single plane and a larger carb would be wise investments. If your drag racing only.