Testing has shown that on a 450HP motor, the RA manifolds are down about 20HP but less than 10ft-lbs over long tubes, and are right in there with shorty headers.
https://www.hotrod.com/articles/hppp...-vs-manifolds/

What they didn't show in there is the loss with factory manifolds on the big engine, but I'm guessing that they'd be down another 10-15HP.

On a less powerful engine, the loss is lower. Since my starting point is definitely on the lower end, I'm going to try the shorty headers for my NA 301.

 

My question isn't about the manifold/hedder comparison, but the need for monster 3" pipes over 2 1/2s. I'm sure there will be a loss with the big pipes when just cruising, but wondering about the gain at full throttle. With the restriction at the RA manifolds, is there a need for big pipes down stream, and will they be a benefit? I know you already purchased them, and are committed, but wondering if you've seen any testing with those manifolds and pipe combos? Thanks.

 

The only testing I have seen was with Dave at SD Performance, he has developed some cams specifically to use the ram air manifolds. His testing with a certain overlaps and the ramp durations show more average power from 2500-5000rpm using RA manifolds, but the long tubes do produce more peak hp by about 10hp, but average power is higher with the ram air manifolds.

I don’t think there is any gain on the 3” duals, but for $350 for a complete stainless system with x pipe, it is better than my old N10 exhaust, I couldn’t pass it up. Plus I may do headers in the future. I have seen some people put headers on these swaps about 15-20 years ago and they cut the #5 & #7 tubes to make it work and reversed them.

 

That is an excellent price for that system. And the future hedder installation makes them even more desirable. Hopefully you'll be styling and cruising this summer. Can't wait to see your finished pics. You're almost there. Thanks again for sharing.

 

Actually I did drive it last fall with the old exhaust. The power and torque from 2500-5000 is amazing, feels like a 600hp car with over 600ftlbs of torque. Just finishing the exhaust and I am able to get the ground clearance by tilting the x pipe. Will get more pictures when done and videos.

 

Afgun, I keep missing your posts. Have you made any progress on your 301T project?

 

Life's been very hectic; I have a spare 301 block in the hole now to establish how it goes there. My cheapo 301 is on a stand disassembled for measurements (it specced out mostly); I'm going to mock it back up to figure out how much deck to cut (it was all over the board, but I want to get it down to around 5-10) before I reassemble it. I have a set of heads that were gone through (seller thought they were NOS, but I got a great deal on 'em, so it's all good). I'm out of town at my mom's right now, so look for some updates starting next weekend.

 

Why are you cutting your deck height? On your mule motor? I thought you were mocking up the block to fit mounts, and hedders to your car. then put in your built motor after.
And I can relate to "hectic". My life has been like that for well over 10 years. I stare at my 84 under a cover, and my 301T in my garage on a stand, dreaming of the day I can put some time on it. Have lots of parts. conversion from TH700, to a T-5, remove the AC evaporator for a conventional heating system, remove the busted power window regulators, and install the mechanical ones. Have al the stuff, just no time. Working for a living really sucks.

When?

 

IIRC (measurements are in the garage at home) I had some slugs over .030 in the hole. Less than ideal if I'm not throwing a turbo on it right away.

 

The 301T block motor I had use traditional heads. What they did was take a torker 2 manifold and cut 1” out of it to make it shorter. It was welded back up and blended to fit the short deck of the 301.

 

I already have a T2 on the shelf, along with a set of mildly ported #16s Going to start with the 301 goofy heads to see what I can do with it, then go from there...

 

Sounds like a cool idea. I guess you would use a band saw to make a straight cut on the flanges, , the same cut on the runners, and tig it back together. Must be a huge improvement, with those heads, over the stock 301heads. And with a traditional crank, you wouldn't be afraid to take it over 6K RPMs.

 

The 301 crank is actually pretty beefy despite the lack of interior counterweights.

 

No disrespect intended afgun, but that's a relative comment. The 301 crank might be considered "beefy", compared to a Briggs and Straton 2 HP lawnmower eng., but I don't know of 1 single example in my 50 yrs of Hi-Perf. Pontiac studies, and experiences, where anyone has taken a traditional Pontiac V-8 and installed a 301 crank for a performance application. But plenty have done the opposite. Not to say in my build, I will be removing the 301 crank in favor of the latter, but my application won't be seeing any hi- rpm encounters. I like the fact the crank is of a light-weight design, and might give some better throttle response, (like an aluminum flywheel), but in no way would I put the crank in a "beefy" category.

 

My 301 had a 1963 forged crank, fit well just need spacers on the thrust bearing surface. That motor made 475hp @ 6000 with Joe Sherman Racing Engines in LA. They shut the dyno down at 6000 and it hadn’t peaked yet. Sherman said that if they spun it to 6500 an easy 500hp in that 301. But definitely not the stock 301 crank….

 

In reality Souperman, the only thing "301" in your motor is the block. And is probably the weakest link, at that point, no?

 

Actually I don’t own that motor anymore, just trying to pass along info if someone wants to build a 301. Yes the only part 301 was the block, but as I mentioned before the turbo block is as strong as a pre 76 400. This motor is ideal for a “pure” Pontiac swap because the 1” shorter deck height helps it fit under the hood of the firebirds. My current car uses a 428, with a WFO shaker assembly it just fits under the formula hood.

 

That is a definite plus, for a Pontiac, in a 3rd gen. Not that the traditional Poncho V8 block is anything to write home about, it will take some power, but not as good as the SD blocks. So, you say the turbo 301 block is stronger than a N/A motor? How and where? seriously, I've never had the opportunity to do a side by side comparison.

 

It’s in the main cap area. Traditional Pontiac blocks up to 1977 had the main caps the same thickness as the supporting webbing. The 1977 blocks introduced where the 557 casting number blocks that the main cap webbing was undercut, losing strength. If you measure a 301T block it will be the same main cap webbing thickness as a pre 1977 block. I don’t know the dimensions off the top of my head, but I have verified this years ago. When a Pontiac block breaks, it’s usually in the main cap webbing up to the lifter bores. It will usually spit up the middle of the lifter bores, it’s weakest point. Having more thickness in the main cap area helps strengthen it.

 

Good to know. Can't say I've ever had a block split on me, and I had a few hi-compression 428-455s built in my day. Can't say any made much over 400 HP tho.
If/ and when I can ever get to my 301T motor, I'll be glad if I can get 250 out of it. My quest for rocket ship motors are behind me. I just want something to cruise the backroads in, and enjoy the New England scenery. Something good looking, and unique. (Like a 3rd gen, with an actual Pontiac V8).
Looking fwd to seeing your machine, completed, and drivable.

 

Afgun, and "Souperman", got your ears on? Curious if either of you guys have made any progress? I know the holidays is right around the corners, and just wanted to say, "Merry Christmas", and hoping Santa brings you some goodies, and me some time.

 

Discovered that with my 3 engines I didn't have a complete set of head bolts. A box with ARP on it should be here on Wednesday and I hope to have more progress over the holiday.

 

Been driving mine, right up to this snow. Runs great no issues. I have some videos but too big to post. I don’t know how to post videos.

 

Excellent, and you'll be that much closer

 

That's OK. Some more photos of your car out, and about would be nice. And more of the underhood.

 

Finally made some time to work on the engine today. Got the cam installed and timing set on - the timing gear was rusting to the crank so took a bit of effort to figure that out. Going to take some parts out for cleaning tomorrow. Slow, sorry!

 

No apology's needed afgun, keep at it, and good luck with it.

 

Been spending some time on my 84, altho not so much for the eng. swap. Well, in a way, I guess you could say, "indirectly". Forget about the window conversion from P/W, to mechanical regulators, (I did do a thread on that). But I did remove the evap case under the hood, and removed all the AC components. Needed the room for the turbo down pipe. Looks like it'll just squeeze in, (when I get there). Not pretty, yet. Just beginning to fit the pieces in.


Also removed the brake booster, to install the 3rd pedals, and research the potential clutch system. Doesn't look like a lot of fun.




Now the quest for a clutch system.

 

You might check out Wilwood. Their masters and slaves are pretty reasonably priced if you can make them work.

 

I've seen a few aftermarket systems, and the prices are atrocious. But I'll check into Wilwood. Thanks. Looking into factory replacement for the master, but might go aftermarket for the slave, due to not using the chevy tilted bell, but the BOP. Might need-ta fab a bracket to mount it. I see them available, but once again, prices are un-reasonable, at least for me.

 

Also you might check the masters from Speedway Motors. Most there line is GM based on the cheap for street stocks. Generally based off of 2nd gen Camaro or G-body. But usually pretty universal. No probably no BOP specific slaves tho.

 

Not sure about how many different configurations there are for slaves and mounting. Research beginning. Thanks for your replies.

 

Yeah I'm not proficient enough in that dept to know. Can't wait to so see what you find out.

 

I'll keep you posted. My vacation ends today, and will be traveling to NH tomorrow, so maybe Sun., I'll get to investigate more.

 

I just went to their site, and as for 3rd gen. Hyd. clutches(?) ...zippo for systems. Maybe some hoses, or fittings, but nothing for masters, or slaves. Actually, I just input those words too, and came up with a "universal" floor mount pedal kit for a couple hundred. Nothing that resembles the factory set-up tho.

 

Oh yeah I wasn't thinking factory replacement, I was just thinking if you used their slave and one of their compact masters. If they would fit.

 

Yeah, I didn't really see anything like that listed. They asked for a car, (make and model) so they could list everything they had for it. But not much came up for clutch parts. Maybe if I worded it differently, or hunted deeper, I could find it, but gave up after a time.

 

Yeah I think they only have the one slave

And they have many masters. I was visioning maybe one of these could work for you? But again Ive not messed with the clutches on these to know what stock set up even looks like.

 

Hey, good find, and thanks for posting. The factory MC seems to have it's mounting flange on an angle, because the firewall isn't flat where it mounts. At least that's what I've seen from pics. Also the push rod has some weird bends in it too. Between the aftermarket cost, and the refabbing needed, I'm trying to find something to bolt on. I realize I'll have-ta fab something to mount the slave, but don't wanna spend the time on the firewall too. Thanks again for the efforts.

 

Yeah that's right the firewall does have some strange angles to it in that area. Have you checked McLeod clutches? I know they were trying to get into more bolt on stuff. And one of the sales guys there has or had a 3rd gen Camaro.

 

I just looked them up, and they do list a MC, (for almost $300) that doesn't include the reservoir, bracket, slave or any other hrdwr. But it "is" a start. I have a line on something, but still researching. I'll keep you posted.

 

are the mounts still available link no longer works

 

I think that company has hit the trail, many years ago.

 

And now, I get to actually participate in this thread "actively." after all these yrs, I've finally gotten this project on the priority list. Not that it'll happen at any excessive rate of speed, but at least I can show some progress. Yesterday I pulled out the 305, to check out the K- frame, and compare mount locations from the Chevy to the Pontiac. And (like confirmed by a few above) the Pontiac required location for the rubber frame mounts, needs to be shoved back an approx. inch or so. the factory metal brackets on the 80 301, appear to be the same 4", as the bow-tie ones, so they will remain. Just need-ta unbolt the frame mounts, and remount them rearward. I'm hoping the pre-drilled holes in the frame, will make this possible, W/O re-drilling.

 

so did u have to drill new holes also what mounts did u use and how hard was it to drill if u had to

 

So here is the "continuation" of the mounts, that has had lots of interest since the beginning.
It appears over the years, there have been a few options. Some mentioned above. The route I'll be taking appears will work, altho I'm not there yet, but closing in on it.

I have an 80 301 turbo motor, and don't know lots about it, cause they're past my time. Wasn't ever a fan of them, but because I have the car, and motor, and because the car has a functioning turbo-bulge hood, I thought it would be a marriage made in heaven. A gutless motor, making minimal power against a light duty T-5, with a glass torsion barred rear end, all attached to a cheesy lightweight unit-body. If I'm not planning on racing the car, I think it'll be a fun driver. I like the styling, and think it would be cool to have a firebird, that actually has a Pontiac motor. Kinda like what Pontiac wanted to do, but GM killed the only V8 motor Pontiac had left, at that time. It'll be my "tribute" 3rd gen T/A.

Because the 80 turbo eng. was built so close to the 82 model, I was "hoping" there would be some useful similarities, or compatible components that would interchange. And in fact, the eng. brackets on the 80 301T, will fit the 84 T/A lower mounts. (4" long). The problem is, those mounts are shaped differently than the Pontiac 2nd gens mounts, and don't allow the rotation or correct positioning to the K-frame. I had to purchase the 80 frame mounts, to get the pair to work as needed.

In the above photo, I've laid it out, so you can see the variations of the Pontiac vs the Chevy mounts. Unfortunately, I was rushed and hadn't noticed I mistakenly got them crossed. (Sorry bout that).
Bolted to the block, the mount on the left, is the 2nd gen Pont. mount, and on the top of the block, the Pont. mount is on the RHS.

You can see the differences in the angle of the ones bolted to the block. The Chevy one is twisted as much as it'll go, and won't meet the angle needed to sit on the frame. The LHS does. On the top, I used a yellow ball marker to highlite the differences that matter. The chevy mount on the left is shaped higher on the curve, and is an obstruction on the Pontiac eng. bracket. The 2nd gen mount on the RHS top, shows the taper needed to clear that bracket. I think if you were ambitious, you might be able to die-grind the brackets, or mounts, to have the needed clearance. But because the 2nd gen mounts are so cheap, I just bought a new set. (the shipping was as much as the mounts themselves)
This week-end I'm hoping to get it lowered onto the K-frame, so I can mark it for the new holes. And "no", there aren't any holes that are "pre-drilled" to fit the mounts. (As many above have mentioned.)

 

Up-dates. Used a temporary block, (455) to fit the mounts to the K-frame. The hole pattern (on the eng.) is the same as the 301, and because I didn't remove the tranny, I used that as my "0" point for the back of the block, and mount location. They seem to fit as needed and I believe bolting them in will be easier to access the nuts, than the chevy mounts. In the photos below, I marked the new holes with a yellow ball marker. The K-frame is beginning to look like swiss cheese. And please excuse the grime, I'm waiting for a replacement pump for my pressure washer to be delivered, before I can clean it all up.

 

Looks good so far man. Which transmission you using? I see you said the trans is in the car, was it the 700r4 that had a universal bell housing?

 

Hello JJ,
Good to see you're back. The tranny presently is a "mule" non-WC, just to try and fit everything together. With the BOP bell, the T5 doesn't look as promising as I was hoping. (As far as ease of fitment goes). In the middle of it all right now. Another choice that might work is a T-56, but I haven't gotten that far yet.

 

I saw you post Joe so I had to respond lol. Still tinkering on my 91 but been preoccupied with my 94 ta and my 85 square body 4wd. The manual tyranny would be awesome in there but I was never a fan of the hydraulic clutches in those cars. Adapting the 301 to the 3rd gen harn3ss wouldn't be too much work but speedo could be issues with the tyranny. I know they make converters for them, I've seen them for sale. Glad to see some progress pics. Hope all is well my Pontiac brother.