Twin-Charged Bonneville running again
#1
Senior Member
Posts like a Turbo
Thread Starter
Join Date: Jan 2005
Location: Atlanta, GA. USA
Posts: 368
Likes: 0
Received 0 Likes
on
0 Posts
Twin-Charged Bonneville running again
I finally rebuilt the 3800 in the twin-charged bonne. I had blown it up pretty bad due to a slipped 1-2 shift and hitting fuel cut under 14psi boost. I made sure to install an MSD DIS-4 system so I now have a soft-touch rev limit. Fuel cut is set at 7500rpm, way out of reach.
The twin liquid-air intercooler system is done, the fan, pump, etc. I ran 3/4" hose twice the length of the car, wye'd it into two 5/8" hoses to each intercooler, and then wye'd it back together to go into the front-mount heat exchanger, then back to the tank (3-gal "bubba keg" in the trunk), and out to the pump which is mounted in the rear of the car under the trunk floor. It is so efficient, it provides ambient air temp in the intercoolers at all times. The temp drop across the turbo i/c is about 10deg and the */c i/c is about 15 deg. Temp drop across the radiator is about 20 deg. It is always ambient air temp coming out of the rad.
I am having trouble with the Walbro fp. Come to find out they don;t run well when not immersed in fuel. The bonne fuel tank is quite wide and 1/4-tank is below the level of the gerotors in the pump! I am looking at a few options, including sumping the tank and running an aeromotive pump system.
The turbo came back from the rebuild ($750.00-worth UGH!!!) good as new. New turbine shaft, new turbine hsg, bearings and seals, too. I am using oil about 1qt/1000 miles. I left a pretty rough finsh in the cyl (hone sucked), so i'm hoping it will seal up after a while. it has about 6-7K miles on it now. It runs very string, but the fuel issues are plaguing me. I plan to run a modified L32 fuel rail and an aftermarket regulator. The stock regulator will only boost-compensate up to 10psi, then it stops rising. Not good when running 16psi+.
I am also running it on a LS1 MAF this time. Once I get the fuel issues worked out, I plan to start tuning it. I'll post as news comes in.
BTW, my Grand Am (see sig) ran at the Pontiac nats last week in Ohio. My new pb for any car I've ever owned: 12.38@117mph. It will go 11'* in the current state of tune with a little more practice launching.
The twin liquid-air intercooler system is done, the fan, pump, etc. I ran 3/4" hose twice the length of the car, wye'd it into two 5/8" hoses to each intercooler, and then wye'd it back together to go into the front-mount heat exchanger, then back to the tank (3-gal "bubba keg" in the trunk), and out to the pump which is mounted in the rear of the car under the trunk floor. It is so efficient, it provides ambient air temp in the intercoolers at all times. The temp drop across the turbo i/c is about 10deg and the */c i/c is about 15 deg. Temp drop across the radiator is about 20 deg. It is always ambient air temp coming out of the rad.
I am having trouble with the Walbro fp. Come to find out they don;t run well when not immersed in fuel. The bonne fuel tank is quite wide and 1/4-tank is below the level of the gerotors in the pump! I am looking at a few options, including sumping the tank and running an aeromotive pump system.
The turbo came back from the rebuild ($750.00-worth UGH!!!) good as new. New turbine shaft, new turbine hsg, bearings and seals, too. I am using oil about 1qt/1000 miles. I left a pretty rough finsh in the cyl (hone sucked), so i'm hoping it will seal up after a while. it has about 6-7K miles on it now. It runs very string, but the fuel issues are plaguing me. I plan to run a modified L32 fuel rail and an aftermarket regulator. The stock regulator will only boost-compensate up to 10psi, then it stops rising. Not good when running 16psi+.
I am also running it on a LS1 MAF this time. Once I get the fuel issues worked out, I plan to start tuning it. I'll post as news comes in.
BTW, my Grand Am (see sig) ran at the Pontiac nats last week in Ohio. My new pb for any car I've ever owned: 12.38@117mph. It will go 11'* in the current state of tune with a little more practice launching.
Last edited by pontiacjeff; 08-18-2009 at 05:25 PM. Reason: add track times
#8
DINOSAURUS BOOSTUS
Expert Gearhead
Here you go guys.. Jeff has some some very cool and interesting things. Like putting a nearly indestructible 4T80 from a Caddy into the Bonne
https://www.gmforum.com/t229424/
https://www.gmforum.com/t229424/
#10
Senior Member
Posts like a Turbo
Thread Starter
Join Date: Jan 2005
Location: Atlanta, GA. USA
Posts: 368
Likes: 0
Received 0 Likes
on
0 Posts
I got fed-up with the Walbro in the car. I think it has been a dud the whole time and why I blew the eng twice. I bougth a new one to try as well as a Mallory 4305M fpr. I am buidling a new fuel delivery system using L32 fuel rails, cut and fittings welded on for a -8 feed line from the regulator, teed into the two rails. All -8 braided lines. I will put the new Walbro in the tank, but might ditch it if it is still a problem. I might just sump the back end of the tank and run an inline HP pump mounted outside the tank. One Walbro is supposed to be good for 500hp. My goal is 400whp, so that should be enough. If I go for more, then two externals will be the way to go.
I'll post some pics when it'* done.
I'll post some pics when it'* done.