[pontiac_boy]

Im looking for some input, Im slowly trying to start piecing parts together for a build ill be working on over the summer. I want to have a car thats pretty well rounded for the street and strip but i may be overreaching. I would like to be in the 600-650 range with the ability to run nitrous at the track if desired. To start this build i have a 70 400 block and I'm working on a deal for a set of edelbrock round port heads that have been ported by SD performance. My first question is whats your recommendation for the stroke that will help me reach those goals? I was looking at the 4.25 or .35 kits from Butler but it was recommended that i look into the 4.5 stroke if I'm going with a forged crank. My plan is to go complete forged bottom end to allow for the nitrous, but I've seen a few people feel that a 4.5 is pushing the limits of the stock block. I haven't looked much into a cam yet, but I'm thinking a hyd roller? I don't plan to daily drive the car, but I would like to be able to jump in it and drive to work, car shows and things like that. As far as racing goes it'll mostly be bracket/index racing with maybe some grudge. It won't see constant doses of nitrous however, id like it to be strong enough to take a healthy shot with some minor changes. Whats everyones opinions/recommendations for reaching these goals? Should I try to locate a 455 block or do you think the 400 will work? I have a budget of around 8K. Any input will be appreciated.

[STEELCITYFIREBIRD]

Vehicle? Condition?
Overall Budget?

Plan for a viable driveline behind it with traction?

Plan on how to get traction?

450-500 HP with traction is way faster, consistant than 650+ without.

[Steve C.]

The 400 block with aftermarket steel main caps using a stud kit. Personally I'd also fill it to the freeze plugs.
.

[1968GTO421]

The 400 block should be more than strong enough as the 3" bores in the main bearing webs leave more webbing than does the 3.25" bores in the 455/428 blocks. (I have a 428 block and know). The stroker kit should give you the cubes you need. Personally I would use the 4.25" stroke as the 4.5" would generate too much piston speed. Butler is a great resource for stroker kits.
http://butlerperformance.com/i-24591...tegory:1234863

The other guru's should give you more explicit advice regarding your heads and cam, etc. Make sure you have a knowledgeable machinist ready to help you with this.

Beat of luck, sounds like a really neat build.

[Steve C.]

Subject of filling block:

http://forums.maxperformanceinc.com/...ght=fill+block



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[ponyakr]

For that power level I'd just save up a few more $$ & go with an aftermarket block & 4.5" stroke. That way you won't need any high rpm to reach your power goals. And you won't have to worry about breaking a stock block--just everything behind the engine.

Spots shows a 505 cast crank shortblock for $6200. So, you can figure an aprox cost for a forged 4.5 crank upgrade.

http://www.spottsperformance.com/IA2%20engine%20block2

Sandoval shows some stock block 4.5 stroker shortblocks for under $6000. Complete engines are over $10k.

http://www.sandovalperformance.com/engines

I'd guess that KRE & Butler prices are higher. So, if you can build what you want for your $8k budget, that's great.

http://www.krepower.com/Pontiac%20Street%20Engines.htm

http://butlerperformance.com/i-24487...tegory:1267471

As for the cam, all of the popular SD HR cams will make 500 or more hp. They advertise that a 114 LSA "Road Paver" cam, in a 535, will make 650hp on pump gas.

http://www.sdperformance.com/listPro...p?categoryID=2

I'd think the "Old Faithful" grind would be more streetable, in stock block engines.

http://www.sdperformance.com/viewPro...productID=1816

KRE sells a similar cam, which has less lift. It's their HR236.

http://www.krepower.com/Pontiac%20Ca...nd%20Parts.htm

Butler also sells a similar cam.

http://butlerperformance.com/i-25039...tegory:1272239

http://butlerperformance.com/c-12722...om-grinds.html

[pontiac_boy]

Its going to go in a 72 Lemans. Ive had the car for about a year and I've been fixing all of the issues rust/body work related. I had to rebuild the transmission when i got it so i had it rebuilt with those HP goals in mind and i have a healthy 12 bolt rear. I planed it so that i can change the rear gears and stall to complement the motor setup. As for the suspension, I have that on my list of things to address but it is not part of my 8k budget.

[tom s]

You want 600-650 on the motor and then the juice on top of that?Might have been better in the race section?Tom

[ponyakr]

Somehow, I don't think you'll need any nitrous, if you build a 600-650hp Pontiac engine. You can just spend all the $$ you'd planned to spend on nitrous, on an aftermarket block instead.

[Singleton]

How much cfm will the heads flow? That's going to be a huge factor in obtaining the 650 goal.

I'm currently building a pump gas 495, (4.185x4.5) using a '70 455 studded 2-bolt block.

Sdperformance 340 cfm e-heads, 10.5 CR, Bullet Solid Roller, (251/262, .388 Ultradyne Lobes), Northwind intake,(sd ported), Holley 950HP. Should be in the neighborhood of 650 horsepower according to SD.

I too, pieced together the parts for this build over a period of time. Caught the forged 4.5 crank on sale at Racing Parts Maximum for $469 and free shipping. Got some unused Molnar 6.7 BBC rods cheap on Racing Junk.com.

For pistons I used Autotec 1000583 pistons, (1.27 pin height), (which are made for a 4.25 stroke, 6.8 rod combo, but works also for a 4.5 stroke 6.7"rod).

[STEELCITYFIREBIRD]

Originally Posted by tom s

You want 600-650 on the motor and then the juice on top of that? Might have been better in the race section?Tom

With fuel system, professional assembly and new appropriate parts your looking @ $12~14K+. You will break driveline... and need brakes to stop it.


My budget allows me to build a Pontimonster, but common sense kicked in and has me not doing it....yet!

I'd say your overreaching, easy to do when your read what's out there.

http://forums.maxperformanceinc.com/...d.php?t=799483

[Steve C.]

Stated- "As far as racing goes it'll mostly be bracket/index racing with maybe some grudge. It won't see constant doses of nitrous however, id like it to be strong enough to take a healthy shot with some minor changes."

I'd be curious to hear more about your racing goals. As it relates to your proposed ET/MPH desires. And of course to be successful at it, setting driver skill aside here, you will need to build the suspension set up for consistency to go rounds. Very important in addition driveline strength !

650 hp and a simple nitrous system can put you into the 9's depending on the race weight involved. Keep in mind the required certified roll cage and window net.

.

[pontiac_boy]

Originally Posted by ponyakr

Somehow, I don't think you'll need any nitrous, if you build a 600-650hp Pontiac engine. You can just spend all the $$ you'd planned to spend on nitrous, on an aftermarket block instead.

Ive never honestly looked into an aftermarket block because i always figured they'd be to expensive. I would prefer to stick with what i have but i won't rule it out.

Originally Posted by Singleton

How much cfm will the heads flow? That's going to be a huge factor in obtaining the 650 goal.

I'm currently building a pump gas 495, (4.185x4.5) using a '70 455 studded 2-bolt block.

Sdperformance 340 cfm e-heads, 10.5 CR, Bullet Solid Roller, (251/262, .388 Ultradyne Lobes), Northwind intake,(sd ported), Holley 950HP. Should be in the neighborhood of 650 horsepower according to SD.

I too, pieced together the parts for this build over a period of time. Caught the forged 4.5 crank on sale at Racing Parts Maximum for $469 and free shipping. Got some unused Molnar 6.7 BBC rods cheap on Racing Junk.com.

For pistons I used Autotec 1000583 pistons, (1.27 pin height), (which are made for a 4.25 stroke, 6.8 rod combo, but works also for a 4.5 stroke 6.7"rod).

Im waiting to hear back after he double checks his paperwork but he was thinking in the 330-335 range for flow. Ive kinda learned over time that what you want and whats actually going to happen HP wise hardly ever match. So with my HP goal of 600-650 I understand that I'm probably going to be closer to the 600 range.

Originally Posted by STEELCITYFIREBIRD

With fuel system, professional assembly and new appropriate parts your looking @ $12~14K+. You will break driveline... and need brakes to stop it.


My budget allows me to build a Pontimonster, but common sense kicked in and has me not doing it....yet!

I'd say your overreaching, easy to do when your read what's out there.

http://forums.maxperformanceinc.com/...d.php?t=799483

The brakes are upgraded to disc on all four corners, the transmission was built with these hp levels in mind, and the driveshaft/rear end will be as well.

Originally Posted by Steve C.

Stated- "As far as racing goes it'll mostly be bracket/index racing with maybe some grudge. It won't see constant doses of nitrous however, id like it to be strong enough to take a healthy shot with some minor changes."

I'd be curious to hear more about your racing goals. As it relates to your proposed ET/MPH desires. And of course to be successful at it, setting driver skill aside here, you will need to build the suspension set up for consistency to go rounds. Very important in addition driveline strength !

650 hp and a simple nitrous system can put you into the 9's depending on the race weight involved. Keep in mind the required certified roll cage and window net.

.

Ive dont a lot of bracket/index racing over the years and its something i really enjoy doing and mostly plan to continue with. That being said grudge and heads up racing is pretty big here so its something id like to give a try. Being a bracket car, a lot of people are going to know what kind of times its capable of so thats when the nitrous would come into play.

I have been looking into suspension upgrades, Dick Miller racing in particular but this will come out of a different budget. ET wise most of the tracks around me a 1/8 mile so ideally id like to be mid 6's on motor. A roll cage and all safety equipment will also be added.

[Steve C.]

Forgot to ask your proposed race weight. But for conversation a 1/4 Mile ET of 10.35 is 6.51 seconds in the 1/8th mile according to one popular calculator. And the horsepower is 669 computed from a vehicle race weight of 3500 pounds and a 1/8-mile ET of 6.51 seconds. This said, a known mph will provide a better indicator of horsepower.


.

[tom s]

Steve,that is HP to the ground or HP at the flywheel?Most calcs use HP to the ground?Tom

[Vengeance Race Engines]

Originally Posted by pontiac_boy

Im looking for some input, Im slowly trying to start piecing parts together for a build ill be working on over the summer. I want to have a car thats pretty well rounded for the street and strip but i may be overreaching. I would like to be in the 600-650 range with the ability to run nitrous at the track if desired. To start this build i have a 70 400 block and I'm working on a deal for a set of edelbrock round port heads that have been ported by SD performance. My first question is whats your recommendation for the stroke that will help me reach those goals? I was looking at the 4.25 or .35 kits from Butler but it was recommended that i look into the 4.5 stroke if I'm going with a forged crank. My plan is to go complete forged bottom end to allow for the nitrous, but I've seen a few people feel that a 4.5 is pushing the limits of the stock block. I haven't looked much into a cam yet, but I'm thinking a hyd roller? I don't plan to daily drive the car, but I would like to be able to jump in it and drive to work, car shows and things like that. As far as racing goes it'll mostly be bracket/index racing with maybe some grudge. It won't see constant doses of nitrous however, id like it to be strong enough to take a healthy shot with some minor changes. Whats everyones opinions/recommendations for reaching these goals? Should I try to locate a 455 block or do you think the 400 will work? I have a budget of around 8K. Any input will be appreciated.

The power level you are trying to achieve is not out of reach for either setup, whether it's with a 4.250" or 4.500" stroke. Personally I don't see anything wrong with a 4.500" crank in a stock block, especially a 400. If you have to spend the money on a crank, why not aim for down the road in case you do go aftermarket block? Unless you happen to score a killer deal on a 4.250".

What it really boils down to is the race weight of the car when all said and done.

[ponyakr]

"...Personally I don't see anything wrong with a 4.500" crank in a stock block, especially a 400..."


I remember when a member of this forum built a 400 block 4.5 stroker that made 750hp + on the dyno. It had unported KRE High Port heads & a solid roller cam. Peak hp was @ 5900 rpm. If I remember correctly, it also made torque in the 700 range.

It had an E-85 Dominator carb, and I believe it had a Northwind intake. Not positive on that. I'll try to find the thread and post it.

http://forums.maxperformanceinc.com/...=695053&page=2

Anyhow, I'd like to know EXACTLY how much price difference there would be between completely beefing up and machining a stock block, for this level, and going with an aftermarket block. I assume this has been discussed many times. Anybody have links to that kind of info ?

[Steve C.]

Tom, I'm not sure. These calculators for intertainment and conversation seem to differ.

This one from Wallace calculates both and suggests different results.


http://www.wallaceracing.com/hpcalculatoreigth.php

Another:

http://www.etcracingprograms.com/etcalc.htm


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