408 Build Thread

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Looks good Brian. Don't it suck waiting on other guys! You probably mentioned it earlier and I missed it but what cam are you running?
 
I'm running a Comp XR292HR-10. Here's the cam card.

camcard0001Medium_zpsbd541567.jpg
 
I'm hoping the torque curve will look like a table, straight up, flat and then fall off. I've got all new suspension, but I think I'm gonna have to start looking for ways to improve traction. Caltracs and slicks come to mind.
 
Brian, do you have informations regarding the piston to valve clearance with this cam and where the pistons are at tdc (zero deck etc.)?

I did no measurements with my existing combo XR286HR and KB356 Pistons....and wanna be sure if there is enough space if i ever change to a bigger cam.

Michael
 
The pistons are at zero. The tops of the pistons were milled .015 which set the quench at .038-.040 Compression is approximately 10.25:1
 
ok, my pistons are a little bit down in the hole, i use a stepped dish piston (the upper part of the step is zero deck).

So if possible i´m pretty interested in some values for Piston to Valve clearance. Do you use 1.6 Rockers?

Thanks!

Michael
 
I have been reading through this and it is awesome to see KC guys on here. I am from Olathe and it would be awesome to meet some of you! Is anybody going to the HPAC show this weekend in Olathe at the Bass Pro? I think I am going to start a thread on the 340 that I am going to build for my 67 dart after reading through this.
 
The machine shop called today while I was eating lunch. Said the engine is running and that they have made a few pulls. The numbers so far are 490 hp and 519 torque. Nice fat torque curve. He wants to play around with jetting and timing because he thinks we can still hit 500 hp.

I'm going to run out there Monday afternoon and watch a couple pulls for myself. I should have video and a maybe a printout to show after that.
 
BrianT said:
The machine shop called today while I was eating lunch. Said the engine is running and that they have made a few pulls. The numbers so far are 490 hp and 519 torque. Nice fat torque curve. He wants to play around with jetting and timing because he thinks we can still hit 500 hp.

I'm going to run out there Monday afternoon and watch a couple pulls for myself. I should have video and a maybe a printout to show after that.
Click to expand...

Cool! Would love to see and hear it :D
 
BrianT said:
The machine shop called today while I was eating lunch. Said the engine is running and that they have made a few pulls. The numbers so far are 490 hp and 519 torque. Nice fat torque curve. He wants to play around with jetting and timing because he thinks we can still hit 500 hp.

I'm going to run out there Monday afternoon and watch a couple pulls for myself. I should have video and a maybe a printout to show after that.
Click to expand...
Totally cool ! !!:cheers:
 
BrianT said:
The machine shop called today while I was eating lunch. Said the engine is running and that they have made a few pulls. The numbers so far are 490 hp and 519 torque. Nice fat torque curve. He wants to play around with jetting and timing because he thinks we can still hit 500 hp.

I'm going to run out there Monday afternoon and watch a couple pulls for myself. I should have video and a maybe a printout to show after that.
Click to expand...

Sounds like good solid (honest..) numbers. I like ,how this is working out for you.
 
Nearly 20 years ago I built a stock stroke 360 with J heads 10.5:1 comp.
The cam in it was a Comp Cam magnum 248@50 with 525 lift (I think).
Anyway, in a full weight Aussie Valiant Coupe (the same as your car) it ran high 11's on pump gas with 3500 stall and 4.11's with full exhaust and street tires.
Im pretty confident your car will be deep in the 11's or high 10's.
Congrats, looking forward to reading more..
 
Thanks everybody. I told Doc that I wasn't hung up on numbers, they are only ink on paper. I think this engine will fulfill my goal of having a fast street car. He agreed, but was disappointed that it didn't hit 500 hp. I have a feeling that he's not done yet.
 
Don't know too* much about engines but can someone tell me what heads you use when building a 408, can you use the 360 heads? Or do they have to be ported? Thanks
 
Scampman71 said:
Don't know too* much about engines but can someone tell me what heads you use when building a 408, can you use the 360 heads? Or do they have to be ported? Thanks
Click to expand...

You would be much better off asking your question in a new thread that is your own thread. Things get confusing when multiple questions are asked in one thread. Start your own thread and I'll input what I know. I'm not an expert but have had a fair amount of experience

BTW: welcome to the board
 
Here is a video as promised from the machine shop. We played around with three different spacers under the carb, but the numbers pretty much stayed the same. No real big gains to be had. Doc also thought that the 1 5/8" headers that they use might be holding it back compared to the TTIs that I'm going to run. Overall, I'm very pleased.

[ame]https://youtu.be/XaB4C6TUWo0[/ame]
 
I pulled my 340 out and put in a 408, still working on tuning but its a big different In the Duster.
 
BrianT said:
Oops, I'm pretty new at video. Try it now.
Click to expand...
Working now . Sounds great , those are impressive numbers should get a few more hp with the new headers , car will be a rocket on the street . Zero to jail time in 8 seconds .
Have some fun with the car.
 
Sounds good Brian. Bigger headers should let it breath better and might very well put you over the 500 hp mark since your already so close. With 520 lbs ft. of torque your gonna have to take stock in rear tires, LOL...
 
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