In a perfect world i would have completely remade the mid pipe, but the Kooks exhaust Nick supplied wanted to be used. Unfortunate that the way its made (which is well) had the 3 bolt flange style connections at the back tails. I wanted to keep the exact same geometry as the exhaust was made, in order to not have the issues out the back and alignment. I looked at the x on the bench and figured with some manipulation i could convert it to a pseudo Y by removing one leg, porting out the crossover and capping one end. The down pipe that wasnt finished was 3.5 od and no real way to make a clean leakproof connection. I flared the spare leg i removed to take up some space for the reducing weld. Coming off the downpipe its right into the leg and then gets split equally at the x with the internal work i did.
The spare leg also had to be sliced and the flange spun in order to meet up to the exhisting 3 bolt on the midpipe. All in all i was quite happy to keep the exhisting exhaust intact, which resulted in a seamless install of the rest out the back. Everything lined up perfect.
Now onto the few things that have to be tweaked.
Im surprised with whomever fabbed the hotside. Everyone knows a wastegate should be mounted at a 45 to the pipe leading the the turbo. We have MAJOR boost creep even with the 44mm gate just running on the spring (13psi/.9 BAR) By the end of the runs its was closing in on 18psi, which deems the controller useless for now until we fix that. I have to drop hot side now and refab. Exhaust has a real hard time making a 90* turn to exit the gate....never gonna control the turbo like that.
At 15ish psi and a lame tune @ 5300 rpm we are alredy well beyond block splitting terr, so new springs and fixing the gate is next in order.
Thanks for the props.
The spare leg also had to be sliced and the flange spun in order to meet up to the exhisting 3 bolt on the midpipe. All in all i was quite happy to keep the exhisting exhaust intact, which resulted in a seamless install of the rest out the back. Everything lined up perfect.
Now onto the few things that have to be tweaked.
Im surprised with whomever fabbed the hotside. Everyone knows a wastegate should be mounted at a 45 to the pipe leading the the turbo. We have MAJOR boost creep even with the 44mm gate just running on the spring (13psi/.9 BAR) By the end of the runs its was closing in on 18psi, which deems the controller useless for now until we fix that. I have to drop hot side now and refab. Exhaust has a real hard time making a 90* turn to exit the gate....never gonna control the turbo like that.
At 15ish psi and a lame tune @ 5300 rpm we are alredy well beyond block splitting terr, so new springs and fixing the gate is next in order.
Thanks for the props.
Tony wanted me to post this up:
"It appears to me they have probably got a very restrictive cat back to the airflow they are running. Just a guess. I have the same thing on my 95 done the same way running a cnc 76 precision on a 351 W with absolutly no boost creep at all in any way. Using a 44mm Tial gate. It is a street car not a race car. The 44 should be able to more then take care of bleeding off the pressure and lbs per minute as needed even if it was 180 to the flow.
Plus I noticed they are running a pt-76 turned down to 500 RWHP? I would never have spec'd that for 500 hp so the additional airfow gotta go somewhere. If he'd turn is up to the 750+ he was probably wanting when I speced it, he wouldn't have any issues at all. That is what causes 9 out of 10 boost creep issues. To be of a turbo turned down to low for a given cubic inch.
Yes merging the wastegate in will help this application, But so would install a proper turbo for the hp desired, Or turning it up to the hp level it was spec'd out for. "
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