just purchased the SPD 3.5L EcoBoost Equal Length Resonator Delete, RDFR20EL
Junior Member
Joined: May 2023
Posts: 23
Likes: 6
love the sound of that.... from what im informed..... they achieved that sound b/c that style or "generation" has smaller turbos and they got rid of the cats while also shutting off the oxygen sensors or tricked em. For obdll.... the oxygen sensors show up as "on standby" if shut off and will cause you to fail emissions. Tricking them seems to work for a little while, so im told.
2018 got bigger turbos... so that whistle sound is not obtainable in its stock form....
2018 got bigger turbos... so that whistle sound is not obtainable in its stock form....
A few guys are working on some potential Equal Length options for 2.7/3.5 non raptor downpipes that should help out the turbo whistle substantially. Most exotic sports car V6's have equal length exhausts from front too back. I wouldve never imagined it would make such a difference but I've learned so much about exhausts in the past few months alone.
One of the guys on the other site has the CRP Stage 4's on his 2.7 and he said the turbo whistle was significantly louder. It's a much bigger turbo then stock
The Cummins Diesels have like 60-70 mm inducers and 80-90 exducers and they whistle like crazy
Last edited by havs54; Jul 3, 2023 at 10:22 AM.
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Joined: Nov 2020
Posts: 740
Likes: 374
From: Chicagoland area in Illinois
Im not so knowledgeable on turbos, its new terrain for me, Lots of variables..
but Id love to have the whistle on mine. Ive been wanting to do the turbo swap, but waiting till warranty is over.
but Id love to have the whistle on mine. Ive been wanting to do the turbo swap, but waiting till warranty is over.
Senior Member
Joined: Jun 2021
Posts: 223
Likes: 543
um...... not completely disagreeing with you ..... BUUUUUUUUUUUUT.....
if you change out the standard cat system on a non raptor f150 with one from a raptor..... you can have the true dual exhaust setup like the h.o. 3.5L its a bolt on swap.
only real physical difference from a non H.O. and a H.O. is the compression ratio in the cylinders and the turbo vanes on the compressor side
Have these laying around waiting to get installed, just dont want to down my truck for the day..... or 2 I have the spd high flow adapters to match
if you change out the standard cat system on a non raptor f150 with one from a raptor..... you can have the true dual exhaust setup like the h.o. 3.5L its a bolt on swap.
only real physical difference from a non H.O. and a H.O. is the compression ratio in the cylinders and the turbo vanes on the compressor side
Have these laying around waiting to get installed, just dont want to down my truck for the day..... or 2 I have the spd high flow adapters to match
