L48 Top end upgrade
Race Director
Joined: Mar 2017
Posts: 11,953
Likes: 4,509
From: Virginia
Hello All,
I'm in the middle of this upgrade and just realized that I messed up. Not sure how I did it but I ordered Brodix heads 158-1021005 roller cam heads (https://www.jegs.com/i/Brodix/158/1021005/10002/-1) instead of what I meant to order the 158-1021004 with is setup for flat tappet.
I was torqueing down the heads and saw the tag on the heads that indicated hydralic roller not flat tappet so luckily I saw it before completing assemby. Unfortunately I had already put in the flat tappet cam and lifters in so I'm hoping that with a good cleaning I can return them to Jegs.
The issue I have now is that I need a roller cam that will work with this combo.
The flat tappet I was planning on using was Xtreme Energy 268H Hydraulic Flat Tappet Camshaft & Lifter Kit Lift: .477" /.480" Duration: 268°/280° RPM Range: 1600-5800
So I'm thinking something similar in a roller cam.
Hoping for some suggestions.
Thanks
I'm in the middle of this upgrade and just realized that I messed up. Not sure how I did it but I ordered Brodix heads 158-1021005 roller cam heads (https://www.jegs.com/i/Brodix/158/1021005/10002/-1) instead of what I meant to order the 158-1021004 with is setup for flat tappet.
I was torqueing down the heads and saw the tag on the heads that indicated hydralic roller not flat tappet so luckily I saw it before completing assemby. Unfortunately I had already put in the flat tappet cam and lifters in so I'm hoping that with a good cleaning I can return them to Jegs.
The issue I have now is that I need a roller cam that will work with this combo.
The flat tappet I was planning on using was Xtreme Energy 268H Hydraulic Flat Tappet Camshaft & Lifter Kit Lift: .477" /.480" Duration: 268°/280° RPM Range: 1600-5800
So I'm thinking something similar in a roller cam.
Hoping for some suggestions.
Thanks
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
In the doghouse!!!
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
Le Mans Master
Joined: May 2007
Posts: 5,028
Likes: 1,120
From: North tonawanda NY
The jist I see is someone bought heads with $150 of springs setup for a roller cam and instead of swapping the springs for weaker 99 dollar beehives for the flat tappet they used it for an excuse to upgrade to a better roller cam and lifters. The final cost, components and HP can only be determined when its said and done... 
OP as someone who went from a 262/268 version of the flat tappet voodoo cam to the xr270hr cam, It was worth it... I did buy my retro roller lifters from rock auto myself which saved me like $300 vs buying them elsewhere but I see the cam literally increased $100 in cost since last spring as well... They were available from multiple places for $285 shipped last year. that along with $130 for the lifters, $20 for the cam button assy, $12 for the brass tipped fuel pushrod and about $50 for the howards hardened shorter pushrods after measuring with my $14 tool from amazon and I was all set. I already had the springs which came stock on my old dart heads before I previously swapped them for weaker flat tappet single springs.
OP as someone who went from a 262/268 version of the flat tappet voodoo cam to the xr270hr cam, It was worth it... I did buy my retro roller lifters from rock auto myself which saved me like $300 vs buying them elsewhere but I see the cam literally increased $100 in cost since last spring as well... They were available from multiple places for $285 shipped last year. that along with $130 for the lifters, $20 for the cam button assy, $12 for the brass tipped fuel pushrod and about $50 for the howards hardened shorter pushrods after measuring with my $14 tool from amazon and I was all set. I already had the springs which came stock on my old dart heads before I previously swapped them for weaker flat tappet single springs.
Last edited by augiedoggy; May 10, 2022 at 08:40 PM.
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
Well I did just replace the springs. I called comp cams and they suggested I remove the center spring and do break in with just the outer spring to ensure the cam is broken in correctly. The springs that came with the heads were ther CC 287 and have open pressure of about 325lb which comp cams said wouldn't be an issue with the 268H flat tappet cam once it's broken in. I fired it up today but have open headers so it didn't really run great. I have appt tomorrow mornig to get headers connected to pipes at local shop since I don't weld. Hoping I'll ba able to tunes once exhaust is setup. I plan on running the single spring for 100 milts then adding back in center spring.
Le Mans Master
Joined: May 2007
Posts: 5,028
Likes: 1,120
From: North tonawanda NY
I was going to actually suggest earlier just leaving the center springs out since the out springs are already stiffer than what you would buy for a flat tappet setup.
I really hope you ran the complete full proper rpms break in procedure and didnt just fire it up and run it in short increments? I'm told that can increase chances of improper breakin.
At least your not in the doghouse right?
I really hope you ran the complete full proper rpms break in procedure and didnt just fire it up and run it in short increments? I'm told that can increase chances of improper breakin.
At least your not in the doghouse right?
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Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
I finished installing IK180 heads, 268H CC flat tappet cam, 2101 intake manifold, timing chian and gear, long tube headers, and 1.6 roller tip rockers. I''ve probalbly spent about $2100 total. Not sure about HP since I still haven't connected exhaust to headers and I'm running some weak springs just to break in the CAM. I'm doing exhause tomorrow and will install correct springs some time next week. Hoping for just under 400HP at the crank.
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
I was going to actually suggest earlier just leaving the center springs out since the out springs are already stiffer than what you would buy for a flat tappet setup.
I really hope you ran the complete full proper rpms break in procedure and didnt just fire it up and run it in short increments? I'm told that can increase chances of improper breakin.
At least your not in the doghouse right?
I really hope you ran the complete full proper rpms break in procedure and didnt just fire it up and run it in short increments? I'm told that can increase chances of improper breakin.
At least your not in the doghouse right?
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
The exhaust is now complete so no more open headers. The car runs great even with the single spring that I removed as mentioned before. Although I still haven't really pushed it feels like it lost some low end torque but more that makes up for it above 3000RPM. Feels like it would keep pushing up power beyond 5k RPM although I'm taking it easy for the 1st 100 miles. I plan on adding back center spring after the 100 miles as well. That should help at higher RPM.
The only issue I have is a bad oil leak in the front of the oil pan. I installed new timing cover by only loosening the pan and I have a leak on passenger side of the pan where it meets up with timing cover. I cleaned and use some sealent so hopefully that will work. Otherwise I'll have to take pan all the way down which is a major pain.
The only issue I have is a bad oil leak in the front of the oil pan. I installed new timing cover by only loosening the pan and I have a leak on passenger side of the pan where it meets up with timing cover. I cleaned and use some sealent so hopefully that will work. Otherwise I'll have to take pan all the way down which is a major pain.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
The exhaust is now complete so no more open headers. The car runs great even with the single spring that I removed as mentioned before. Although I still haven't really pushed it feels like it lost some low end torque but more that makes up for it above 3000RPM. Feels like it would keep pushing up power beyond 5k RPM although I'm taking it easy for the 1st 100 miles. I plan on adding back center spring after the 100 miles as well. That should help at higher RPM.
The only issue I have is a bad oil leak in the front of the oil pan. I installed new timing cover by only loosening the pan and I have a leak on passenger side of the pan where it meets up with timing cover. I cleaned and use some sealent so hopefully that will work. Otherwise I'll have to take pan all the way down which is a major pain.
The only issue I have is a bad oil leak in the front of the oil pan. I installed new timing cover by only loosening the pan and I have a leak on passenger side of the pan where it meets up with timing cover. I cleaned and use some sealent so hopefully that will work. Otherwise I'll have to take pan all the way down which is a major pain.
1980 CHEVROLET CORVETTE Fel-Pro OS34510T Fel-Pro Oil Pan Gaskets | Summit Racing
Might as well replace the rear main seal while you're in there, too.
Scotty
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
If you end up having to remove the oil pan, this one-piece oil pan gasket from Fel-Pro is the bee's knees.
1980 CHEVROLET CORVETTE Fel-Pro OS34510T Fel-Pro Oil Pan Gaskets | Summit Racing
Might as well replace the rear main seal while you're in there, too.
Scotty
1980 CHEVROLET CORVETTE Fel-Pro OS34510T Fel-Pro Oil Pan Gaskets | Summit Racing
Might as well replace the rear main seal while you're in there, too.
Scotty