Author Topic: 1991 360 for my '72 Challenger? (Read 6727 times)

Swedee · « **Reply #15 on:** September 22, 2015 - 03:41:04 PM »

Quote from: Chryco Psycho on September 22, 2015 - 03:26:50 PM

No . could be the factory cam

According to the seller it's some sort of a Comp street-cam that was supposed to be new but even my untrained eye can say that's not new..

Check out my blog at www.my72challenger.com

Swedee · « **Reply #16 on:** September 24, 2015 - 03:23:24 PM »

Had another look at it tonight. To me it looks like it says either "1992" or "1332"

That doesn�t help me getting any specs anyway though

Chryco Psycho · « **Reply #17 on:** September 24, 2015 - 09:49:11 PM »

sure doesn't look new to me , pretty good track through the center of all the lobes .
could be the year 1992 , if the block was cast late in 91 & assy in 92
could be 1552 also , you can measure across the low part side to side of the lobe & the high part top to bottom & get the lift from it , probably .280 range

Swedee · « **Reply #18 on:** September 25, 2015 - 08:39:33 AM »

Ok, let�s forget about this cam. Had a discussion with the seller about this and turns out it was a mistake from his side. Got the same amount back that was on the receipt i got with the engine.

In about 3 weeks we�re going to the US for Nascar at Talladega and Martinsville, and will get the chance to visit the Summit store in Georgia right before we head back home. Thought that would be a great oppurtunity to get a new cam (along with a long list of other stuff)

I have no idea what to get but i�m pretty sure the good people at cuda-challenger.com can point me in the right direction

So, my setup is as follows:
Untouched 360 block with Bad P 290 flat pistons. About 10.5:1 compression.
308 heads.
Weiand dual plane intake
Edelbrock 750 carb

Stock 904 gearbox
Stock converter

Patriot headers
Magnaflow 15851 dual exhaust

That�s about it. I would sure appreciate your recommendations!

Thanks, and have a nice weekend!

Chryco Psycho · « **Reply #19 on:** September 25, 2015 - 09:54:19 AM »

I would just talk to Lunati directly tell them what you have , they have a series of VooDoo hyd rollers , I have used a couple of them but mp specific grind I can recommend to you

Swedee · « **Reply #20 on:** September 28, 2015 - 10:46:47 AM »

👍 Sent them an email today, hopefully they'll have something that suits my setup.

Check out my blog at www.my72challenger.com

Swedee · « **Reply #21 on:** September 29, 2015 - 03:30:39 PM »

Sorry for bothering with another probably very stupid question but I feel I should get this straight before I settle on which cam to get..

Since this is a 89-91 360, I believe it was equipped with EFI from the factory. I'm gonna run this with my Edelbrock 750 carb and mechanical fuel pump. Summit, for instance recommends this (http://m.summitracing.com/parts/cca-20-614-9) cam for my setup, but it's computer controlled. This doesn't make sense.. And when I look at the Voodoo roller cams for using with mech fuel pumps (https://www.lunatipower.com/ProductGroup.aspx?id=360&cid=61), they state that they might need "computer modifications".
If someone could set things straight, it would be greatly appreciated.

Check out my blog at www.my72challenger.com

Chryco Psycho · « **Reply #22 on:** September 30, 2015 - 10:05:24 PM »

increased duration will mess with the Map sensor so you have to run open loop with preset parameters to work with the computer , the carb can be dialed in to work using different parts so no big deal

Swedee · « **Reply #23 on:** October 01, 2015 - 12:56:01 AM »

Thanks for clarifying!

Check out my blog at www.my72challenger.com

moper · « **Reply #24 on:** October 02, 2015 - 08:38:34 AM »

The problem you're having is the tech guys are looking up an application for the EFI because by year that's what you have. The early EFI engines had the same timing over as the old ones, so a fuel pump bolts right on them. So you can treat it like any pre-Magnum 360 engine. So you need a retrofit hydraulic roller grind. Not a replacement EFI hydraulic roller. However, you need to know if the heads have any performance work done. I tend to think no based on the cam choice. So - be aware that the heads will probably need a bit of work to replace that cam with anything more performance oriented. Work meaning new exhaust valves to replace the ones made to be sed with exhaust valve rotators, and either spring seats and guides cut, or the new valves with new beehive springs, plus their special retainers, and locks. My recommendation would be the Comp Cams XR268HR-10. But really anybody's cam will be fine as long as you keep the duration at .050 under 225 degrees.

Swedee · « **Reply #25 on:** October 06, 2015 - 04:04:34 PM »

Thanks Moper! Looks like no work has been done to the heads. I do plan on changing to the beehive springs. However I won't change the exhaust valves now as this build is draining my wallet enough anyway. I'll have that done down the road though..
For now i'm just planning on getting the motor running, a little beefier than stock.

Check out my blog at www.my72challenger.com

moper · « **Reply #26 on:** October 07, 2015 - 09:37:36 AM »

Quote from: Swedee on October 06, 2015 - 04:04:34 PM

Thanks Moper! Looks like no work has been done to the heads. I do plan on changing to the beehive springs. However I won't change the exhaust valves now as this build is draining my wallet enough anyway. I'll have that done down the road though..
For now i'm just planning on getting the motor running, a little beefier than stock.

Check out my blog at www.my72challenger.com

If you change to beehive springs, you have to replace the retainers and locks. The issue will be the exh valve for use with the valve rotators has the lock grooves cut at a taller location than the none rotator valves. So the spring pressures will be lower on them and I'm not sure if the new retainers will work on them. You may be better served by leaving the heads and cam alone, or running something that is much smaller - like less than 218� duration at .050, and under .460 lift - but for a carbureted engine. Or simply by buying a set of stock replacement 340 exhaust valves which are the same physical size in every dimension, but have the grooves cut in the right spot. Lap them in and you "should" be good to go with whatever you want.

Swedee · « **Reply #27 on:** October 08, 2015 - 03:21:53 PM »

Quote from: moper on October 07, 2015 - 09:37:36 AM

If you change to beehive springs, you have to replace the retainers and locks. The issue will be the exh valve for use with the valve rotators has the lock grooves cut at a taller location than the none rotator valves. So the spring pressures will be lower on them and I'm not sure if the new retainers will work on them. You may be better served by leaving the heads and cam alone, or running something that is much smaller - like less than 218� duration at .050, and under .460 lift - but for a carbureted engine. Or simply by buying a set of stock replacement 340 exhaust valves which are the same physical size in every dimension, but have the grooves cut in the right spot. Lap them in and you "should" be good to go with whatever you want.

Thanks Moper, I really appreciate your input.

If I go ahead and have the valves changed and the additional work done to the heads, what cam would you recommend based on the rest of the setup?

Thanks!

Check out my blog at www.my72challenger.com

moper · « **Reply #28 on:** October 08, 2015 - 08:50:41 PM »

Quote from: Swedee on October 08, 2015 - 03:21:53 PM

Thanks Moper, I really appreciate your input.

If I go ahead and have the valves changed and the additional work done to the heads, what cam would you recommend based on the rest of the setup?

Thanks!

Check out my blog at www.my72challenger.com

I went to your blog. You mention a "Bad P 290" piston. Those are Badgers, and they are cast stock-type flat top replacements for the mid 70s to early 80s 360s. They are not anywhere near 10.5:1. They are not performance pistons. Given the block and heads you have, using a common head gasket, you have a true static compression ratio of about 7.8:1. This is not meant to beat you up -there's nothing wrong with a solid stock bottom end. So - with replacing the valves and updating the valves and retainers- I'd look at a milder camshaft. Something in the 220-230 degrees at .050. There are plenty available but you have to match the springs to the cam and some manufacturers like more spring. I would look at the Comp XE line (my truck has the XE262 and it's very torquey) the XE268 would be the largest I'd run because it's the biggest you can run with single springs. The VooDoo Lunatis are good too, but watch the springs - they all call for dual springs even when the cam is smaller. In terms of a great budget cam - the Summit K6900 is also very good - and cheap, and needs a cheaper spring... win win win there.

Swedee · « **Reply #29 on:** October 16, 2015 - 05:21:19 AM »

Thanks again Moper! You're soo right about the compression.

I actually dropped of the heads earlier this week at the machine shop to clean them up and to shave them off a little. By shaving them .0787 inches the compression will end up at around 9.7:1.
I'll stick with the stock valves for now.

I've decided to go with Comp's 20-810-9 which is within your recommendation. I'll get the matching springs and retainers at the same time and the machine shop will open up the spring seats for the the new springs as well.

Check out my blog at www.my72challenger.com

Author Topic: 1991 360 for my '72 Challenger? (Read 6727 times)

Swedee

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

Chryco Psycho

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

Chryco Psycho

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

Chryco Psycho

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

moper

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

moper

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?

moper

Re: 1991 360 for my '72 Challenger?

Swedee

Re: 1991 360 for my '72 Challenger?