Topic: &9 Firebird Engine swap.

[PaulHomer]

I'm getting things ready for swapping a 301 out for a 400 (Pontiac of course). In doing my research I found that the '79 400 had different motor mounts. Can I use any 400 or only the '79? Will I need custom mounts? Any suggestions on which block to use?

[brian c]

The external dimensions of the 301 and the 400 match so you should be able to reuse your motor mounts without any issues. It's one of the most popular swaps around - 301 to 400 - as its pretty much drop in. That I believe was for the 70-79 blocks. 

The only change was during the 60's where they had a different number of mount points so it's not a drop in per se. It is once you purchase a set of adapter mounts though

[PaulHomer]

Thanks. That's what I was hoping. Any suggestions on a Specific block number to use? My experience is that there were no bad 400s.

[brian c]

Depends on your goals. Some guys swear by the older 70-73 blocks (could be higher, not really sure) due to the higher nickel content. Others say, depending on your goals, that any of the 400 blocks will work. I believe the cutoff is around 500 hp but don't quote me on that.

Talk with Geno (72blackbird) or Jim (Mr. P-body) for more details. Both are highly recommended/respected here.

Personally, I have a 70-73 block sitting in my basement waiting to go into my 80 firebird once I get the funds. I'm very seriously considering having Jim build it as he's only a day trip away from me. I'd have Geno do it but I don't think that I could carry a 400 and put it in an overhead compartment for the flight out to CA

[PaulHomer]

Looking for as much power out of her as possible yet still street-able. I've been checking out some of the prices on heads and for what they're asking for iron heads I'm pretty sure I'm going aftermarket aluminum. Could use some recommendations there also. Thanks. 

[brian c]

Personally, I'd use KRE over Edelbrock. Here's my thinking....the KRE's are D port while the Edelbrocks (the last I looked) were still round port. This gives me more opportunities with exhaust manifolds - and yes I'm going back to manifolds when, not if, my headers rust out. I'll be going with RARE in the 2.5" outlet variety.

My setup is somewhere just south of 400HP and it's street able. With 3.42:1 gearing outback it's fun but my gas mileage suffers. Eventually I'll be switching to a 200R4 so that I can get my gas mileage up while maintaining my "fun" factor

Best thing to do is decide which builder you're going to work with and then stick with them throughout the entire build. Different builders have different ideas on how to maintain your power goals and switching mid stream (or trying to cobble something together from multiple opinions) could result in a lack of attaining your goals.

[PaulHomer]

Thanks for reminding me about KRE. The D-port gives not only more options but as I recall less expensive exhaust options also, not to mention that from what information I've been able to attain they also perform better than the Edelbrock head. Also I agree with staying with one shop. My mentor (R. I. P. Ed) taught me a long time ago (1978) the importance of properly matched parts.

[brian c]

IF you're looking for recommendations on builders, here's who I would trust (in no particular order):

Jim (Mr. P-body)
Geno (72blackbird)
Paul @ Spotts Performance - I have dealt with him several times for (2) different builds
K&S Auto - I hear they are "the" shop to go to in my area for engine builds.
Butler - If $$$$ were no object

I'm kicking around having Jim build my next engine as he's only a day trip away. Unfortunately, those I listed are not near you so you'd need to be willing to travel a bit. I'm sure there are some members around in your neck of the woods that can recommend a builder if needed.

[PaulHomer]

I'll be doing most of the actual build myself, one of the things I really enjoy about building a car, but really appreciate the info on who to contact for recommendations on parts. Like I said earlier the local horsepower guru passed away a few years ago and considering he helped me get a street-able 500 hp out of a Chevy 283 I'd say he knew his stuff, and he was a BIG Pontiac buff so I pretty sure if he was still around I'd be getting a lot more out of the 400. One of the things I'm looking for right now is someone to do the machine work. Unfortunately the best around here is also gone. He still did Babbitt bearings until he passed about 10 years ago. Unfortunately the true art of engine building and machine work has been replaced with technology. Part of the art is being able to deal with all the variables involved with building and machine work, something a computer just can't do.

[72blackbird]

Hi Paul,
500 hp from a 400 is possible with out a stroker kit, but it would require ported aluminum heads that flow over 300 cfm, 93 octane, and a serious tune- this combo would also haved to be revved to 5000-5500, not a big deal but a bit much on a regular basis for a Pontiac V-8. This output is alot easier coming from a 400/461 stroker combo- it can make 500 hp from stock e-heads or KRE's and do this at least 1000 rpm lower, saving wear and tear on the engine.

A 70-75 no.481988 400 block is the best candidate for your build- it has 5 mounting holes per side and will drop into your 79 Bird w/o adapter brackets. 4-bolt caps are nice, but even a 2-bolt 400 block can support 600 hp- stock bolts will work, but ARP main studs are preferred for performance builds.

I get most of major parts like pistons, rings, rods, bearings, cams, etc. for my builds from Pacific Performance Racing. Ken 'Ace' Brewer has been building high-performance Ponchos for over 24+ years and is one of the most knowledgeable builders I know. He can guide you in the right direction in putting together your parts list for your build, and has all the parts you need to build a nice performance Pontiac V-8.

Geno

[72blackbird]

Brian,
Thanks for the kind words- it's an honor to be even mentioned in the same post as the other builders you spoke of, and there are plenty of other well-known Pontiac builders all over the country (almost too many to mention here). I've spoken to Jim Lehart on more than one occasion and he's truly a Pontiac master builder, as well as being a good guy and easy to talk to- you won't go wrong w/ having him build your next 400.

Geno

[PaulHomer]

Thanks, I'll have to check him out. Like I said most, if not all the true HP artists have long since passed around here and most of the "rodders" around here think performance comes from a computer program. Still looking for an excellent machine shop. I've pretty much ruled out iron heads, if you can find a good pair it costs almost as much as aftermarket aluminum.