L8t 427 Whipple charged Denali

[WestTxDenali]

So I’m in the middle of swapping my tired l86 out with a l8t stroker with a gen 5 whipple on top with all the supporting mods. Trans was built by tkr to hold 1000hp with a circle d billet converter. The issue that I am running into is a good choice for a drive shaft. Seeing that it’s 65 inches critical speed is going to be an issue. Does anyone have a go to for long high horse power drive shafts?

 

[K2 Kaiju]

I dunno your answer, but keep updating this build!

 

[WestTxDenali]

I’ll try my best. I work out of town a lot and am hoping to have my short block up on the stand next week to get pushrod lengths and what not.

 

[randeez]

So I’m in the middle of swapping my tired l86 out with a l8t stroker with a gen 5 whipple on top with all the supporting mods. Trans was built by tkr to hold 1000hp with a circle d billet converter. The issue that I am running into is a good choice for a drive shaft. Seeing that it’s 65 inches critical speed is going to be an issue. Does anyone have a go to for long high horse power drive shafts?

welcome to the forum
https://pstds.com/ did a 3.5" chromoly/billet ends for mine, its only like 50" tho (shorty/4wd)

 

[WestTxDenali]

welcome to the forum
https://pstds.com/ did a 3.5" chromoly/billet ends for mine, its only like 50" tho (shorty/4wd)

I was going to reach out to them on Monday and see what they might have to offer

 

[WestTxDenali]

Quick update. I reached out to gulf coast driveline and ended up scoring a 4 inch t8 driveshaft that will hold well over 1000hp. For anyone wondering a 2wd shaft on a swb is 56 inches center to center without the yoke.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

 

[WestTxDenali]

Quick update before I get the heads back on. Got the pushrods measured out all within 7.95 to 7.97 with the Johnson tie bar lifters. Still waiting on the c5r timing chain to come in from Katech. Ended up ditching vvt all together and went with the LME set up. For the money this piece is mint. Super quality and an amazing fit. Had to go ahead and ditch the crap rubber engine mounts and went with atomic. Again these guys knocked it out of the park with the fit and quality.
The head gaskets should be here either Monday or Tuesday and then I’ll have to head back to work over in midland for a few weeks. Over all I’m super stoked for the build and the wife is getting pretty excited for have her Mommy Missile just about buttoned up.

 

[randeez]

View attachment 419999Quick update before I get the heads back on. Got the pushrods measured out all within 7.95 to 7.97 with the Johnson tie bar lifters. Still waiting on the c5r timing chain to come in from Katech. Ended up ditching vvt all together and went with the LME set up. For the money this piece is mint. Super quality and an amazing fit. Had to go ahead and ditch the crap rubber engine mounts and went with atomic. Again these guys knocked it out of the park with the fit and quality.
The head gaskets should be here either Monday or Tuesday and then I’ll have to head back to work over in midland for a few weeks. Over all I’m super stoked for the build and the wife is getting pretty excited for have her Mommy Missile just about buttoned up.

looks like fun - whats the plan for fueling that 1000hp?
katech will mod the whipple for port injection iirc

 

[WestTxDenali]

looks like fun - whats the plan for fueling that 1000hp?
katech will mod the whipple for port injection iirc

Fic lt4 30 over on the high side walbro 525 on the low side. Gpi cam has a 32 over fuel lobe and then a lt4 high side pump. Unfortunately there is no E85 close to me at all and with this being a daily driver driving 45 minutes to fill up isnt in the picture. It’ll be tuned on 91 pump gas. I’m hoping to see 700ish to the wheel with low boost.

 

[CMoore711]

This is shaping up to be a great build!

I don't have any personal experience with TKR, but they're located about 30 mins south of me and have a very strong reputation for GM transmissions.
What year is your Denali?
Do you have the 8 speed or the 10 speed transmission?
Stall speed on the Circle D Billet Torque Converter?
L8T 427... I'm guessing you installed a stroker kit that bumped the displacement up to 7.0l from 6.6l? What stroker kit did you use to do this?
What are you using for heads on this L8T?

 

[WestTxDenali]

This is shaping up to be a great build!

I don't have any personal experience with TKR, but they're located about 30 mins south of me and have a very strong reputation for GM transmissions.
What year is your Denali?
Do you have the 8 speed or the 10 speed transmission?
Stall speed on the Circle D Billet Torque Converter?
L8T 427... I'm guessing you installed a stroker kit that bumped the displacement up to 7.0l from 6.6l? What stroker kit did you use to do this?
What are you using for heads on this L8T?

It’s an 8l90. I went with a 3k triple disc setup from circle d. The rotation assembly is all cali compstar stuff. Heads are a set of katech cnc ported stock casting heads. With the 59cc chamber it’ll be right at 10.8:1 so it should have some good grunt down low.

 

[WestTxDenali]

It’s an 8l90. I went with a 3k triple disc setup from circle d. The rotation assembly is all cali compstar stuff. Heads are a set of katech cnc ported stock casting heads. With the 59cc chamber it’ll be right at 10.8:1 so it should have some good grunt down low.

Also it’s a 2016

 

[randeez]

Fic lt4 30 over on the high side walbro 525 on the low side. Gpi cam has a 32 over fuel lobe and then a lt4 high side pump. Unfortunately there is no E85 close to me at all and with this being a daily driver driving 45 minutes to fill up isnt in the picture. It’ll be tuned on 91 pump gas. I’m hoping to see 700ish to the wheel with low boost.

search around on the hptuners forum...a lot of tuners not very happy with fic30%s
xdi injectors seem to be more favorable
no cam in my gen v, but likely going port injection (well am going port injection ive got the plates/injectors, just sorting out controller)

 

[WestTxDenali]

search around on the hptuners forum...a lot of tuners not very happy with fic30%s
xdi injectors seem to be more favorable
no cam in my gen v, but likely going port injection (well am going port injection ive got the plates/injectors, just sorting out controller)

I was heavily considering xdi however they are backordered like crazy and the tuner I use often isn’t a fan of their support. I was thinking of port injection but I think the 30% overs will be fine for what I have going on

 

[randeez]

I was heavily considering xdi however they are backordered like crazy and the tuner I use often isn’t a fan of their support. I was thinking of port injection but I think the 30% overs will be fine for what I have going on

gotcha, if your tuner is comfortable with them , then hopefully it all goes smooth.
if i were up for doing a cam now i would likely just do the DI stuff as well and not have to mess with additional stuff, avoiding meth for the same reason...this thing sits for a few weeks at a time i dont want to have to check abunch of stuff before i drive it every time.

 

[WestTxDenali]

gotcha, if your tuner is comfortable with them , then hopefully it all goes smooth.
if i were up for doing a cam now i would likely just do the DI stuff as well and not have to mess with additional stuff, avoiding meth for the same reason...this thing sits for a few weeks at a time i dont want to have to check abunch of stuff before i drive it every time.

That’s kinda my thinking also working out of town and having the wife daily it. Trying to keep the down low drivability as tame as possible and not overly complicated.

 

[koachdaddy]

Not to derail your thread, but could you tell me why you went with Whipple? I'm on the fence about the Whipple vs Magnuson and trying to ask the questions before making a decision.

 

[WestTxDenali]

Not to derail your thread, but could you tell me why you went with Whipple? I'm on the fence about the Whipple vs Magnuson and trying to ask the questions before making a decision.

The magnuson is awesome for sure. I ended up going with the whipple because it was on sale. I saved a good chunk of change on it.

 

[WestTxDenali]

Finally back from work and had an hour or two free to get some stuff taken care of. I ended up pinning the crank just to be safe with the whipple. All pushrods have been put in a the preload set for the Johnson racing tie bar lifters. Tomorrow or the next day I’ll end up finishing up with the long block and hopefully have it dropped in. I do still need to finish removing the from end to make running lines and what not easier.