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pacman1969 10-02-16 06:33 AM

turbo?
 
12a bridgeport...my motor builder says wont hold up to turbo....why? and if so why would a small turbo hurt?cant get ahold of builder latly to ask why,and trying to fix cutting out issue....but when done would like to put at least a small turbo.

lastphaseofthis 10-02-16 07:35 AM

stock port=small turbo..
Bridgeport, big big turbo 700hp range.. 12a dont hold 700 hp without major mods to the block.

you cannot run a small turbo on a bridge.

pacman1969 10-03-16 03:56 AM

well then......guss thats done!

WANKfactor 10-03-16 04:10 AM

Since when did you have to run 700hp on a bridgeport? There's no reason you cant run 5-6psi, and 300 hp. A decent sized hot side would be fairly mandatory. I can see no reason why you couldnt use an s300 on low boost. Will still be good up to 500hp if you wanted to turn the wick up.

lastphaseofthis 10-03-16 10:20 AM


Originally Posted by WANKfactor (Post 12111841)
Since when did you have to run 700hp on a bridgeport? There's no reason you cant run 5-6psi, and 300 hp. A decent sized hot side would be fairly mandatory. I can see no reason why you couldnt use an s300 on low boost. Will still be good up to 500hp if you wanted to turn the wick up.

since you can make 700 on stock ports.. :scratch:

WANKfactor 10-03-16 03:14 PM

Just because you can (*cough cough* Bullshit) doesn't mean you must.

Even a high flow s5 turbo would work. they make well over 300hp. I had one on my extended port 13b. There is no reason you cant put one on a bridgeport 12a, its not as if it hasn't been done before.

lastphaseofthis 10-04-16 08:30 AM

i'm gonna stand back and let someone else school you.

WANKfactor 10-04-16 02:28 PM

Likewise.

FührerTüner 10-04-16 02:37 PM

You can run a small turbo on a bridge port. It will have a narrow power band but you can do it.

WANKfactor 10-04-16 02:48 PM

It will still have a broader band than NA. As long as the turbo isnt so small that it chokes out at moderate to low boost pressure. Bridgeports tend to get a turbo up and spooling pretty good.

FührerTüner 10-04-16 02:58 PM


Originally Posted by WANKfactor (Post 12112374)
It will still have a broader band than NA. As long as the turbo isnt so small that it chokes out at moderate to low boost pressure. Bridgeports tend to get a turbo up and spooling pretty good.

It would need a really small hot side, right? I would tend to think too large of a hot side would cause more of a restriction than anything.

WANKfactor 10-04-16 03:09 PM

Not really. My thoughts are; its an NA bridgeport 12a, assuming high comp rotors and no extra strengthening on the keg, so it goes pretty good as is but wont like being fed 400psi like our mate lastphase suggests, more like 5-10psi. So a turbo with a pretty good size hotside shouldnt be a problem since it should go pretty good off boost anyway, and the aggressive exhaust pulses of a bridgeport gets a turbo spooling faster anyway. End result, as long as you're not choking the exhaust or the intake with something too small it should drive like an na bridgy but with more torque and power.
Correct me if im wrong, im just putting it out there.

pacman1969 10-05-16 05:00 AM

ok...im lost on what a good size hot side is...i know nothing of a turbo sept what ive heard here and there...please dumb it down for me! i do have skilz,built manny a hot rods,last being a scratch built 399 stroker s10 that turnd a 9.62 and was a dayly driver,but its my first roatry and not dont know much on turbo end.also running a msd 5a dig on leed side using 1 pickup in stock dist and 2nd as stock set up...having a cutting out around 5,500rpm and up,didnt do it before.ive switchd pluggs around,changed carbs (had starvation in hard corners) and cant chase it down,new pluggs? change dist?coil breaking down,its a duel output coil on the msd running direct and using pickup in dist for trigger.

lastphaseofthis 10-05-16 07:32 AM

i wasn't suggesting that he needs to run high boost.. just a large turbo, bridgeports like to flow.

i was trying to point out what no body seems to get, a bridgeport isnt a magical design that makes then all great all the time, its just a way of acheiving high over lap.. and its the 2nd way to do it, the best way to do it is with a peri port... but if you cant run a p port for rules of racing or financial reasons.. you can run a bridge port to get an NA engine over 250 hp...

however if you can run a turbo, there is no reason to port the block at all. rx72c, made 703rwhp years ago on pump gas and some AI.

its easy to make 400-500 hp on stock ports, and when you pick your turbo carefully, and wisely, you can have a setup with great spool, decent economy, and great street ability...

the only guys that SHOULD run a bridge port, are guys trying to get 700-800-900 hp range, turbos that big are hard to spool with stock ports. so something has to be done....

they guys that i typical have seen that have a turbo bridge are... usinga cummins diesel turbo becaus it was cheap.. or using an old used t04e because.... it was cheap..
basicly instead of buying into newer turbo tech.. they just bridge there shit and use something cheap.

now the problem i keep seeing all over lousville ky and here in this thead, is the desire to have a brigeport, for whatever reason somebody told em its great, brap brap, yeah brigdeport..
and a large misunderstanding of how turbos work... how sizes play there part..

i would be curious of what a stock turbo does on a bridge port, i have a feeling its going to hit its spool rpm say 2600... and spool very quickly, but then choke out by 4k rpm... and the power platue at around 4.5k and 280 hp. and then fade off from there.

its also going to be a heat bomb.

FührerTüner 10-05-16 08:07 AM


Originally Posted by pacman1969 (Post 12112531)
ok...im lost on what a good size hot side is...i know nothing of a turbo sept what ive heard here and there...please dumb it down for me! i do have skilz,built manny a hot rods,last being a scratch built 399 stroker s10 that turnd a 9.62 and was a dayly driver,but its my first roatry and not dont know much on turbo end.also running a msd 5a dig on leed side using 1 pickup in stock dist and 2nd as stock set up...having a cutting out around 5,500rpm and up,didnt do it before.ive switchd pluggs around,changed carbs (had starvation in hard corners) and cant chase it down,new pluggs? change dist?coil breaking down,its a duel output coil on the msd running direct and using pickup in dist for trigger.

Starvation in the corners could be fuel tank baffles. Id check there first.

WANKfactor 10-05-16 02:36 PM

I wouldnt use a stock turbo, a high flowed/hybrid one would probably be good but maybe a touch on the small side. I'm guessing anything that flows about 300+rwh and still has a fairly big hotside will do the job. 62mm s300 with a 1.10A/R hotside would probably do the job but you will have more compressor than you'll know what to do with at half a bar boost. Will spool a bit slower but delivery will be beautifully linear and great efficiency too.
Nothing wrong with a bridgeport, and there's nothing wrong with turbo-ing an NA bridgeport either, just dont go crazy with big boost and make sure your fueling and ignition are spot on.
Sorry i can't help with your ignition woes.

pacman1969 10-06-16 05:03 AM

yea come tax time gonna get microsqurt set up fo it to hopfuly solve fuel problems,then if stiff a cutting out problem ill try a reman dist....then if it all works out ill look for a turbo and see just what itll do! thanks for all the info on turbo...hopfully i can fidure out the cutting out issue.


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