fjh Posted January 29, 2020 Share Posted January 29, 2020 (edited) 2005 AI We have an 370 hp engine that has had a 460 ac cam installed in it the engine pulls like a Bear! How ever Eats turbos every year or so! We are entertaining installing all the early 2003 manifolds and 5 inch exhaust ! do you guys think this will help or slow down the turbo fail rate or accelerate the turbo issue! The turbo is the stock AI turbo shaft modified ! I'm no expert on turbo geometry Even prior to the cam the engine had lots of failures Blow by into the base via the turbo drain! The customer now has the turbos custom built with a double seal ring on the shaft that used to be done when the stealth brake was around ! He claims the boost is up over 40 psi !😨 So will it spool more or less with the old style manifolds and 5 inch exhaust ! Either way it will be an experiment gone wrong or gone right or no change if we follow through on it! Would like some ideas here! Kinda worried were going to mess up a the stew here by adding to much salt! Edited January 29, 2020 by fjh Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/ Share on other sites More sharing options...
Mack Technician Posted January 29, 2020 Share Posted January 29, 2020 (edited) Engine’s breathing, no scavenge bump, but has all the exhaust restrictions holding back? You can only improve that mess. I’d do the 5” + manifold with the turbo OldRedMack, Burrens, and now Ditch Digger is installing on their 370’s. I think O.R.M. Said it’s a Borg Warner s467 he got from YTS. Only pure modification you can do to a stock AI turbo is melting it down and turning it into a different series turbo......IMO. Edited January 29, 2020 by Mack Technician Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441524 Share on other sites More sharing options...
fjh Posted January 29, 2020 Author Share Posted January 29, 2020 (edited) 13 minutes ago, Mack Technician said: I’d do the 5” with the turbo OldRedMack, Burrens, and now Ditch Digger is installing on their 370’s. I think O.R.M. Said it’s a Borg Warner s467 he got from YTS. Bro I'm concerned about the out come of the hardware changes here! How will it effect that turbo ? That turbo is already breaking shafts! we are going to let it breath even more if we change the manifolds and 5 inch it! not committed yet how ever I believe if we do the 5 inch pipes and muffler on the out side we likely will be safe BUT doing the manifolds could be asking other for problems!? Edited January 29, 2020 by fjh Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441525 Share on other sites More sharing options...
Mack Technician Posted January 29, 2020 Share Posted January 29, 2020 Duty cycle type shaft breakage on the current 300 series turbo is not going to be an issue once your upgraded to a 400 series. Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441533 Share on other sites More sharing options...
OldRedMack Posted January 30, 2020 Share Posted January 30, 2020 So it's a 370 with a 460ac cam. Is that all the mods? Do you know what the egt's are? Is it an electronic boost gauge or manual? If it's a manual gauge is there a lot of needle deflection? Sorry for all the questions, just wanted to know all the variables. In the end though, that s300 and ai manifold are only useful as a paper weight. Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441552 Share on other sites More sharing options...
fjh Posted January 30, 2020 Author Share Posted January 30, 2020 Thanx for the replies guys ! Yup correct . Stock gauges electric! The ETs Unknown, Boost is over 40 bumping 42! I'm told, No other mods yet other than the cam. He is and we are reluctant to change much as the only real issue is poping a turbo every several years now . It is a tandem gravel hauler! And that turbo issue had been on going since the truck was born, Kept failing by way of boost down the turbo drain into the base! We removed the exhaust this time to get the oil out . the 4 inch exhaust clear and the muffler is straight thru no restriction other than not being 5 inch! Don't want to mess with the engine file cause it pulls so well! sorry got no more than that ! He has reordered the the turbo( BD is building it ) and is and sticking with the tried and true! I guess So we will not see an out come from this conversation (! It will always be A what if!) Any predictions if we did change the manifold and exhaust ? I wish we had an open cheque book here but pebble packin only pays so much! 😡 Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441568 Share on other sites More sharing options...
Mack Technician Posted January 30, 2020 Share Posted January 30, 2020 Go on Page 6 of the AI page and follow SparksRacing, he did what your doing. My prediction is a slight decrease in turbo longevity from jacking the Delta P by increasing the exhaust output and decreasing post turbo restriction. He’ll feel a slight lag time increase, but no power losses. Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441584 Share on other sites More sharing options...
Jamkar Posted January 30, 2020 Share Posted January 30, 2020 Fred which turbo is he going with? Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441595 Share on other sites More sharing options...
fjh Posted January 30, 2020 Author Share Posted January 30, 2020 Modified stock turbo two shaft seals! To elevate the blow by issue be aware we’re putting this back the way we found it as he declined putting manifold change as to not mess with success! Didn’t want to risk going backwards! Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441600 Share on other sites More sharing options...
brenner Posted January 30, 2020 Share Posted January 30, 2020 Not sure what the issue is Fred but you guys changed mine over about 12 years ago and its still the same turbo the truck came with. 22300 hrs on it now 1 Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441601 Share on other sites More sharing options...
fjh Posted January 30, 2020 Author Share Posted January 30, 2020 It’s kinda Of an odd issue Zak this truck has always had this issue! Not sure yours is pounding out the same boost this puppy is making!who knows it may be driver related too not sure! Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441604 Share on other sites More sharing options...
brenner Posted January 31, 2020 Share Posted January 31, 2020 (edited) Yeah mine is still around 32-33 psi same as stock but I would be curious what kind of temps he is seeing on the pyro. I remember mine dropped a solid 250 degrees after the swap Edited January 31, 2020 by brenner 1 Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441608 Share on other sites More sharing options...
OldRedMack Posted January 31, 2020 Share Posted January 31, 2020 (edited) I wouldn't think the manifold swap would accomplish much because if remember right the s300 has the smaller restricted ports leading to the turbine. Anyway you can talk him into installing a pyrometer? How much is the modified stock turbo costing him, I think you can pickup a generic s400 for under a thousand. Edited January 31, 2020 by OldRedMack Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441610 Share on other sites More sharing options...
fjh Posted January 31, 2020 Author Share Posted January 31, 2020 Hes having the mod done himself ! Can't tell ya that at the moment I will ask! You are correct the turbo inlet is restrictive I agree with your prognosis AND I'm not positive he isn't having other mods done! As Zak stated His boost is at a more normal 33 Usually you got to add fuel to get boost ! So that said Unless I'm getting BS Numbers on the boost! I have to see ? I will see what kind of pyro he's seeing? All this is here say At this point! It Maybe his 42 is actually 32 in which case Its in the ball park! I would like to drive this my self and see what is actual happening ! I'm wondering if they are not giving the turbo a chance to cool after a work out causing this life shortening of the turbo ! Also! If this thing was over fueling I would expect to see Blue Manifold and turbo snail evidence! These look normal they haven't been getting hot! how ever if it is ramming air in at 42 psi we might not see this heating evidence ! Just my observations! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441658 Share on other sites More sharing options...
Mack Technician Posted January 31, 2020 Share Posted January 31, 2020 16 hours ago, brenner said: mine dropped a solid 250 degrees after the swap How much swapping did you do for yours? Cam? Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441669 Share on other sites More sharing options...
fjh Posted January 31, 2020 Author Share Posted January 31, 2020 (edited) Brenners was just the Ac cam as well. The hours speak for them selves! Edited January 31, 2020 by fjh Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441671 Share on other sites More sharing options...
brenner Posted January 31, 2020 Share Posted January 31, 2020 6 hours ago, Mack Technician said: How much swapping did you do for yours? Cam? Just the cam to get the drop in egt Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441709 Share on other sites More sharing options...
brenner Posted January 31, 2020 Share Posted January 31, 2020 7 hours ago, fjh said: Hes having the mod done himself ! Can't tell ya that at the moment I will ask! You are correct the turbo inlet is restrictive I agree with your prognosis AND I'm not positive he isn't having other mods done! As Zak stated His boost is at a more normal 33 Usually you got to add fuel to get boost ! So that said Unless I'm getting BS Numbers on the boost! I have to see ? I will see what kind of pyro he's seeing? All this is here say At this point! It Maybe his 42 is actually 32 in which case Its in the ball park! I would like to drive this my self and see what is actual happening ! I'm wondering if they are not giving the turbo a chance to cool after a work out causing this life shortening of the turbo ! Also! If this thing was over fueling I would expect to see Blue Manifold and turbo snail evidence! These look normal they haven't been getting hot! how ever if it is ramming air in at 42 psi we might not see this heating evidence ! Just my observations! Hey Fred is his manifold cracked? I know these stock manifolds like to crack with even moderate amounts of heat since I'm ready for my third one now and would be a telltale if he is pushing the numbers he is claiming Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441710 Share on other sites More sharing options...
fjh Posted February 1, 2020 Author Share Posted February 1, 2020 13 hours ago, brenner said: Hey Fred is his manifold cracked? I know these stock manifolds like to crack with even moderate amounts of heat since I'm ready for my third one now and would be a telltale if he is pushing the numbers he is claiming Nope manifolds are in good shape! Quote Link to comment https://www.bigmacktrucks.com/topic/60745-370-hp-cam-changed-to-a-460-cam-what-would-you-expect-to-see/#findComment-441734 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.