BUILD THREAD “The Juggernaut”

[Rktpwrd]

What's the CR gonna be?

I’ll have to calculate it again with whatever head gaskets I end up using this time, but it should be right around 9.8:1. At least that’s what it was with the old cast iron heads, but it seems to me that I had them milled a bit to up the CR. I may need to do that to these as well for the same reason.

 

[Supercharged111]

I’ll have to calculate it again with whatever head gaskets I end up using this time, but it should be right around 9.8:1. At least that’s what it was with the old cast iron heads, but it seems to me that I had them milled a bit to up the CR. I may need to do that to these as well for the same reason.

Damn, do you have hella dished pistons?

 

[-dw-]

Yep, I feel ya. My stock heads were/are J heads too, along with a “oh, I know a guy that can port those for ya” port job on them that I’m quite convinced were hurting power. That’s part of the reason I’m so stoked to finally get my hands on a set of these.
These aluminum heads were part of the game plan all along.

Well I don’t any good reason right now to swap them out. I broke the internet 20yrs ago when I said J heads do work good with some porting. With a lot of work and bigger valves they really work well. I was learning at the time and did all the work myself. These days it’s tedious to work iron. Plenty of alum options it’s a no brainer.

 

[Rktpwrd]

Damn, do you have hella dished pistons?

Yeah, they’re old school TRW forged aluminum with a dish from back in the day before there were any options for big Oldses. A lot more options out there now, but I really don’t wanna tear into the perfectly good bottom end to change pistons. Not unless I absolutely have to, to achieve my power goals. Not to mention the cost expenditure.

 

[Rktpwrd]

Well I don’t any good reason right now to swap them out. I broke the internet 20yrs ago when I said J heads do work good with some porting. With a lot of work and bigger valves they really work well. I was learning at the time and did all the work myself. These days it’s tedious to work iron. Plenty of alum options it’s a no brainer.

Agreed. I’m not convinced that the porting job that was done on my heads was good though. Very easy to screw up a set of heads by porting if you don’t know what you’re doing. All it takes is to get into the short turn radius’s.
Before I parked it, the car ran 13.1 seconds in the quarter at over 100 mph at 3500 feet elevation, but only made 282 rear wheel HP and approximately 300 ft lbs torque on a Mustang chassis dyno. It should’ve made much more power than that for the combination of parts I had in it IMO. Granted the power hungry TH400 was eating a lot of it, but still.

With those low wheel HP numbers but respectable quarter mile times, I’m guessing I was making very good use of the power I had and had it pretty much optimized. Looking to do MUCH BETTER than that this time around.

 

[Supercharged111]

I get it, it just sounded odd that, with 77cc chambers, you'd need to shave those heads to get 9.8. A 454 Vortec with 100cc heads has 9:1 and the turd TBI 454 with 118cc heads was 7.9:1 or so. With a 77cc chamber on one of them I'd venture to say you'd be north of 10:1 without a shave.

 

[Supercharged111]

Agreed. I’m not convinced that the porting job that was done on my heads was good though. Very easy to screw up a set of heads by porting if you don’t know what you’re doing. All it takes is to get into the short turn radius’s.
Before I parked it, the car ran 13.1 seconds in the quarter at over 100 mph at 3500 feet elevation, but only made 282 rear wheel HP and approximately 300 ft lbs torque on a Mustang chassis dyno. It should’ve made much more power than that for the combination of parts I had in it IMO. Granted the power hungry TH400 was eating a lot of it, but still.

With those low wheel HP numbers but respectable quarter mile times, I’m guessing I was making very good use of the power I had and had it pretty much optimized. Looking to do MUCH BETTER than that this time around.

Mid to upper 300s crank sounds about right with some not awesome heads. And yes, I know. . .

 

[Streetbu]

Coming home from work today was better than Christmas morning!

The (late) Holley rollover vent valve arrived today…

View attachment 215262

…as did the 10’ of -6 AN hose I ordered for the 2 vents I plan on making:

View attachment 215264

The K&N breather that I’m going to connect to the factory pickup vent is on the way, and should arrive tomorrow.

View attachment 215261

But the absolute icing on the cake, was the email notification I got from Summit Racing. After a full 2 month wait, my aluminum Edelbrock cylinder heads have shipped!!
😍😍😍

View attachment 215263

They should be here this Thursday, so incredibly stoked to finally get a set!

Also, I’ve been in contact with Turna about the Sick Speed Monte clutch pedal bracket, I should probably say hi to all you mongrels from him.
😎

Happy you got your parts finally. Interested to see what your experience is with the sickspeed bracket as compared to mine.

 

[Rktpwrd]

Happy you got your parts finally. Inyetested to see what your experience is with the sickspeed bracket as compared to mine.

I haven’t fully pulled the trigger on the Sick Speed bracket yet, I’m comparing and weighing my options on it still. The one I’d really love to use is the Three Pedals setup (just the pedal and clutch master assembly), but the website says they’re back ordered until April.

’78 – ’88 GM G-Body Pedal Assembly – Three Pedals

threepedals.com

I fully welcome your experiences with the Sick Speed bracket, how do you like it? John says he loves his.

 

[Streetbu]

I haven’t fully pulled the trigger on the Sick Speed bracket yet, I’m comparing and weighing my options on it still. The one I’d really love to use is the Three Pedals setup (just the pedal and clutch master assembly), but the website says they’re back ordered until April.

’78 – ’88 GM G-Body Pedal Assembly – Three Pedals

threepedals.com

I fully welcome your experiences with the Sick Speed bracket, how do you like it? John says he loves his.

Honestly Ive nothing but problems with it. The geometry is not correct and Bernie doesn't want to admit it. All of my parts are bone stock, GM replacement parts. So it's not a Chinese part quality issue. I didn't have enough throw to even bleed it in the first place. He emailed a template so I could drill and tap a new hole, lower on the pedal. I did that and that's how it's been since. I STILL don't have enough throw. I'm literally 95% of the way there. I have to bury my foot into the pedal and the clutch just barely drags. There is more throw on the clutch master, just the pivot is incorrect. I cannot simply drill another hole further down for multiple reasons. The pushrod is at max angle into the mastercylinder. Second off. My clutch pedal is already 2" higher than my brake pedal. If he would just admit there is an issue I'd be much happier. But selling them as a "bolt in" solution is a straight up lie. I could use a larger master cylinder, but the master will hit on the upper control arm.
What I'll have to do is remove the bracket, cut it on the side where it's welded, take it to work and add a few degrees of bend to the portion where the master mounts, so the pushrod will be at the correct angle. Reweld, install, then drill ANOTHER hole in the pedal further down to get full movement of the factory GM master cylinder.