'61 Bonneville Bubbletop

[TheMonkey]

project is a '61 Pontiac Bonneville bubbletop.

plan is a ground up restoration with my son who is 14 now. i've done a handful of wrenching, but this will be the first bottoms up project, and the plans are becoming more & more ambitious.

i found a project car that has everything but the engine/tranny/driveline. looks a bit rough, but that's how we wanted it. sort of our own Flight of the Phoenix project.

455 is at the shop now getting the treatment. full blueprint with new eagle H beam rods & dished Wiseco pistons. 72cc E heads will get 10.25:1 CR. this combo is supposed to be good for 93 octane, particularly since i plan on a megasquirt EFI system. i have not decided on cam grind yet, but recon i will end up with hydraulic roller. not too nasty though, because driveability is more important than shaving tenths. maybe XR276HR?

tranny will be 4l80e. i have a TH400 in a '61 Bonneville convertible, and there seems to be loads of room left in the tunnel. i think the fit should not be difficult, except header collectors might be in the way of linkage. as of now, i'm looking at the TCI controller, although by the time i'm tuning, there might be other cool products avail.

rear end will be stock with the huge early pontiac rear end, although i need to upgrade to posi & config the ratio.

not sure about frame mods yet. i'll be visiting a couple restoration shops to discuss body work & any frame changes. biggest tires i could fit in the back of my convert was 245; not terrible, but wide enough? front end geometry is a struggle as it comes stock.



also not sure on the look of the car. i imagine a stance that is mildly lower than stock. i like the look of 17's, but could be talked into 18's. would really like to have a black car with red interior, but jury is still out if the body can be prepped for that. i would like to have a custom dash, but would need to outsource the design, that is out of my league. the 4l80e accepts a paddle shifter, so bring it on.

i imagine the exhaust to be headers into x-overs and through some really big free flowing mufflers. i don't get too excited about loud exhaust.

i do not know how to properly design the combo for cam + torque convertor + rear end ratio. i still need to define exactly my plan for what i want, but like i said, my goal is driveability and be able to put a lot of miles on it with very few of them actually displaying monster acceleration.

i'll post some pics as it sits soon, and you will see exactly how ambitious this is....

welcome any encouragement, and thanks in advance for any help.

cheers,
Scott.

[Ralph LoGrasso]

Welcome to the site, Scott. It sounds like you've got a cool project on your hands, keep us updated.

[Mr.VENGEANCE]

yet another Bonneville!

great im not alone! welcome!

[ProTouring442]

Did Pontiac use the X-frame like Chevrolet? If so, be sure to brace the rear controll arm mounts! I grabbed a nice second gear in my '61 Impala and ripped the right lower right off of the frame. Made for a VERY interesting ride! First time I really learned what "pucker factor" meant!

Shiny Side Up!
Bill
'72 442 "Inamorata"
www.FQuick.com/ProTouring442

[TheMonkey]

Did Pontiac use the X-frame like Chevrolet? .....

the bonneville frame is full perimeter without the x (if i understand the comparison correctly).

i won't be jamming more torque through than others before me, but i will consider some frame reinforcements & mods while i have the opportunity.

[ProTouring442]

the bonneville frame is full perimeter without the x (if i understand the comparison correctly).

i won't be jamming more torque through than others before me, but i will consider some frame reinforcements & mods while i have the opportunity.

Ok, more like the Oldsmobile then... Kinda wierd that they all used the same body, but different frames then.

Shiny Side Up!
Bill
'72 442 "Inamorata"
www.FQuick.com/ProTouring442

[Damn True]

Welcome, but geeeeez, post a pic dude!

My wife and I saw a really nice '60 Bonny at a Goodguys show last weekend. I'd like to see the differences.

[dipren443]

Seriously though, this is probably one of the "prettiest" designs from GM in the 60's. Awesome project, I have been looking for a good project 61 bubbletop for a little bit now...

Oh, and post some pics

[TheMonkey]

okay.... use your imagination, because i sure am.

as it sits:




and the following one belongs to a friend in town. this car is also the reason i lusted after a hardtop. i have this in a convertible too, but i really like the bubbletop better. this one is an amazing example. it has the '61 425A tripower with custom paint from the factory. some Pontiac people are going to be upset with what i'm going to do to mine, but i can't wait to get started.

[TheMonkey]

my convertible

[Damn True]

Damn, that IS cool!

I think I'm still partial to the '60, but you got yerself one heck of a nice car there! Can't wait to see it take shape.

[TheMonkey]

Damn, that IS cool!

I think I'm still partial to the '60, but you got yerself one heck of a nice car there! Can't wait to see it take shape.

thanks DT. my wife is pretty anxious to see it take shape too. not all of us are able to see potential....

[6'9"Witha69]

She will see it. It is just a long road sometimes. Welcome to the site. Coll project you have there.

[TheMonkey]

car still at body shop... these just back from machine shop (fuel rails & mpfi provisions on manifold are custom)

[TheMonkey]

finally back from the body shop a couple weeks ago. i'm working on reassembly now. motor is complete, and running MPFI. i'm nibbling on the weekends, so i expect to be rolling next Spring. that leaves me the Winter to tie up details. i have nearly everything ready; interior, bumpers, trim, etc...

i have the 4 link rear suspension replaced with tubular arms and poly bushings installed. still not sure what i'm going to do with the front geometry and caster.

trans will be TKO600 instead of the 4L80E.

pontiac 455 +.030 motor made 527hp 550tq at the dyno through cast exhaust & with carb for break-in. mild idle with 14" vac. cam is HR 230/236/112.

[Rubes]

Sweeeet!!!

[Mr.VENGEANCE]

dont you just love bubbletops..

[Tiger]

love them bubbletops!! lease post more pics as you procede

[BobB66SS]

Nice! My '61 Impala bubble top is at about exactly the same point. Keep the pics coming.

[subtlez28]

Too cool!
I love it!
Nice choice!

Please, keep the build pics coming!