[X72GPX]

There are quite a few threads on this and I have read Jim Hand's book. I have a 72 GP with a 400 and 6x-8 heads and a Qjet. Runs great- except I want to be in the 350-400 rear wheel hp range. Should I go with ported KRE 72 cc E heads and a summit 2801 cam with 355's out back? It's an automatic with 28'' tires. It's a heavy street car (4000 lbs) with occasional track runs. I definitley want the idle to rumble with a nice lope to it and hopefully run high 12's. Also which converter do you recommend?

Thanks

[bobzdar]

Originally Posted by X72GPX

There are quite a few threads on this and I have read Jim Hand's book. I have a 72 GP with a 400 and 6x-8 heads and a Qjet. Runs great- except I want to be in the 350-400 rear wheel hp range. Should I go with ported KRE 72 cc E heads and a summit 2801 cam with 355's out back? It's an automatic with 28'' tires. It's a street car with occasional track runs. I definitley want the idle to rumble with a nice lope to it and hopefully run high 12's.

Thanks

Ported KRE's would be way overkill for that cam, or that cam would be way underkill for those heads.

[steve25]

Stock E heads will kill off a good bunch of needed torque with a 400 cid and that 4000 lb car, if you want to go to aftermarket good flowing heads get the kre D ports.

[KS circutguy]

Eheads or KRE's will make 70hp more than any 6x setup.Remember too the 6x's will have to be milled (mine took .090 mill) to get compression up.
Mine run's easy 12's on the motor,weights 3900lbs.
specs.
• Pontiac 400 CI block 1973 2 bolt main
• Bored +.060 over to 411.6834”
• Block torque plate bored and honed
• Mains align honed w/ARP main studs installed
• Crank is 73 400 Nodular iron turned .020-.020
• Block decked to .00 deck height
• Brass freeze plugs installed
• Pistons-Ross Custom racing flat tops +.060
• Rings Sealed Power Total Seal Classics w/ductile iron moly coated top ring each ring file fit to bore
• Rods-Eagle steel 6.625” long ESP H beam w/ ARP bolts
• Federal Mogul Trimetal 3/4groove main bearings +.020
• Clevite 77 rod bearings +.020
• Precision Blueprinted melling oil pump & new billet drive shaft
• Clearance at .0025 mains and .0025 at rods
DCI Graftite rear main
• Complete assembly balanced
• Canton road race oil pan installed with crank wiper
• Heads 6X Pontiac w/bronze guides, new hardened seats stainless steal valves, port matched, ported in bowl area, and short side radius, w/ exhaust cross over filled
• Heads milled .090 to achieve a 9.2 to 1 compression ratio
• Cometic head gaskets and ARP studs
• Competition Cams # 995-16 springs steel retainers w/10 degree locks
• Competition Cams roller rockers 1.52 ratio, Crane Cams cool nuts
• Ultra Dyne solid lifer cam duration @ .050 Intake 243 - Exhaust 251 and Lift @ Intake .518 @ Exhaust .520 w/1.53 rockers Lobe center is 112 installed 8 degrees advanced to 103.5
• Flow Tech (by Holley) ceramic coated headers 3” collectors flowing to 2-1/2” X pipe and Magna Flow mufflers
• Edelbrock Performer RPM manifold w/ Carb Shop Custom Q-jet carb
• MSD billet distributor w/ 15 degrees initial 36 total, MSD 6AL box with rev limiter and MSD Blaster SS coil
• Custom built Continental tight 10” 3200 stall converter
• Turbo 350 trans by Hughes
• B&M Quicksilver shifter
• 8.5” 10 bolt with Auburn posi and 3.90 gears, Moser axles 28 spline
• Southside lift bars
• NOS Cheater nitrous system adjustable from 125HP-250HP
• Aeromotive fuel pump, Comp Engineering fuel sump, flowing threw Aero @ Russell hoses to Aeromotive regulator
• Paint is code #29 GM Dark Blue metallic
• All work performed by owner except machine work by Archie S. at Somers machine shop, and Karl Boe for the tuning help!

[screamingchief]

I seriously doubt you'll ever be able to get 350 to 400 RWHP from that 2801 cam.

Dont care what heads are used either.

With good head flow,the 2802 cam might get you 325ish RWHP +/- a bit either way depending on other various specifics.

My choice would be the 72cc 290 KRE D's and a crower # 60310 solid with 1.65 rockers.

With a free flowing intake and exhaust tract that combo should clear 350 RWHP easily enough,and should move that heavy car into the twelves.

Use a 3000 ish converter like the ever popular continental converter,dont skimp here,every ¢ spent here will be well rewarded in all aspects later on.

[X72GPX]

Originally Posted by screamingchief

I seriously doubt you'll ever be able to get 350 to 400 RWHP from that 2801 cam.

Dont care what heads are used either.

With good head flow,the 2802 cam might get you 325ish RWHP +/- a bit either way depending on other various specifics.

My choice would be the 72cc 290 KRE D's and a crower # 60310 solid with 1.65 rockers.

With a free flowing intake and exhaust tract that combo should clear 350 RWHP easily enough,and should move that heavy car into the twelves.

Use a 3000 ish converter like the ever popular continental converter,dont skimp here,every ¢ spent here will be well rewarded in all aspects later on.

Thanks- What's the ballpark $$ for the Continental? Does that mean from a standing point the car won't launch until 3000rpm? Is that high for a street car? Would I be setting myself up to fail if I did all this work with a stock rotating assembly?

Thanks

[PunchT37]

Originally Posted by X72GPX

Thanks- What's the ballpark $$ for the Continental? Does that mean from a standing point the car won't launch until 3000rpm? Is that high for a street car? Would I be setting myself up to fail if I did all this work with a stock rotating assembly?

Thanks

About $600`ish for a "tight 10" from Continental. And no, it won`t need to be at 3 grand to take off. It`ll feel like stock under lower power driving but will "flash" when you hammer it.
On the bottom end, I would at least get forged pistons. Then, for the price you`d pay to re-use the stock rods, you might as well get the 5140 Tomahawks from Ace at PPR.

http://www.pacificperformanceracing....-bearings.html

[KS circutguy]

Chief,sometimes u worry me.

Dont care what heads are used either.

The heads are always a good investment!

[KS circutguy]

screamingchief ;

Occupation
Was an auto tech,now????
step off dude/

[screamingchief]

KS,your creating drama where there does'nt need to be any,it was a simple comment,and I damn well have a right to say what I want to on this forum,why your taking issue with it is way,way beyond me.

All that comment was intended to say was it did'nt matter what heads were used with the 2801 cam,with that cam,I simply felt he would'nt reach the power/ET goals he clearly stated he's after.

Now go back,and read my whole post,,,I clearly suggested he get the aluminum heads amigo...

Originally Posted by screamingchief

My choice would be the 72cc 290 KRE D's and a crower # 60310 solid with 1.65 rockers.

Never said the aluminum heads were'nt a worthwhile investment,never even implied it.

If that's how you took that comment,that's on you,not me!

Now about your "step off" comment,not a chance,I did'nt start slinging the $#!t here.

[screamingchief]

Originally Posted by X72GPX

Thanks- What's the ballpark $$ for the Continental? Does that mean from a standing point the car won't launch until 3000rpm? Is that high for a street car? Would I be setting myself up to fail if I did all this work with a stock rotating assembly?

Thanks

Punch T37 explained it pretty clearly,but if that's not clear enough there are tons and tons of threads on converters here,and specifically the continentals.

Just search the archives,should be hours of reading on the subject.

[Cliff R]

Agreed, there is a LOT of good information on converters.

Here's a few comments to save some search time.

The converters "rated" stall speed is more for advertising than anything else. As a general rule, the smaller the diameter, 13", 12", 10" etc, the higher the stall speed will be. The larger converters simply move more fluid per revolution of the crankshaft, which combined with the correct other internals make them tend to be more efficient at lower engine rpms. Converters respond to input torque, and the more torque thrown at them, the "looser" they will tend to be in actual use.

Most off the shelf converters, TCI, B & M, etc, that are mass produced and sold at speed shops, discount performance outlets, etc, will not work well behind a high torque Pontiac engine. They are typically built and rated for low compression small displacement engines.

For example, we tested a "shelf" 10" converter some years back, advertised to stall around 3200-3500rpm's. A stout 455 sent it to at least 4500rpm's, and it was EXTREMELY "loose" at any load or throttle opening, requiring nearly 3000rpm's just to back the vehicle out of the driveway!

A 10" Continental converter, built specifically for a 455 engine making over 500ft lbs torque, will "flash" to about 3200-3400rpm's on a full throttle start with traction, but drive pretty much like a stock converter for "normal" driving. Requiring only normal throttle openings and and rpms to move the vehicle around. We use their "Jim Hand" version in our car, it drives pretty much like a "stock" converter, and it will NOT hold past about 1900rpms on the brakes and applying the throttle.

Another BIG variable with converters, is how well they are coupled above the stall speed. Some will slip 1000rpm's, or more, at full throttle in high gear going down the track, as was the case with the 10" unit we tested some time ago.

Our Continental unit shows us less than 200rpms slippage in high gear at the track, or very well coupled above the stall speed.

This is one area of the hobby where you do get what you pay for, and it can be the single biggest vehicle performance improvement, pound for pound and dollar for dollar.

We have been using, recomending and selling Continental converters for at least 7 years now, and have had ZERO returns, ZERO problems, and the only complaints we get are NO TRACTION!.......Cliff

[KS circutguy]

I was out of line.

[screamingchief]

It's cool by me KS,as we all know around here,I been there,done that myself as well.

So I deserve catching some static from time to time no doubt.

Just did'nt think this was one of those times...

I try to do my part to resolve my misdeeds too,so I can respect that it takes a decent fella to do the same.