Camshaft grinds for turbo

fastback · Post by **fastback** » Sun Aug 12, 2007 2:22 am

nice info here.
anyone have som dyno pull's that show torque and HP graph.
together with some other engine spec would be great.

richie,uk · Post by **richie,uk** » Fri Aug 17, 2007 6:01 am

iswinkels wrote:I've had 3 turbo engines so far. The first was a 1641cc with CB's 2242 294 intake duration cam with 1.25:1 rockers which made for 0.530" at the intake valve. Heads were stock CB 044's with dual springs. Made 165rwhp and the power was strong from 3700-6800 with a GT28-320 turbo and 16lb boost. 7.46:1 compression. 1 5/8" CB hideaway header. Intercooled and EFI with 380cc injectors and MSD ignition.

The second engine was a 2332 with a TCS10 cam and 1.25:1 rockers. Heads were 46x38 valved CB comp eliminators. 7.8:1 compression. Custom 1 1/2" header with a GT28-320 turbo and 12lb. Massive torque that peaked around 3500rpm. Ran out of power by 5500ish. 5.325" conrods and a short rod ratio are about the other factors. Also intercooled with EFI and 660cc injectors and MSD ignition. Never dyno'd due to discovering a lifer failure in progress (despite running 2000k's on single springs).

The new engine setup is a 2332 with a Web 86b 112LC with pauter 1.3:1 rockers. Heads are CB comp eliminators with 48x40 valves, CNC ported with Kmotion springs. Lift at the valve is just under 0.500" from memory. Custom 40mm ID exhaust header match ported to the heads with twin GT2554R turbo's running sequential bi-turbo configuration. 5.5" rods, 7.8:1 compression. Also intercooled with EFI and 660cc injectors, Distributorless 2 coil MSD waste spark ignition.

Hopes for the new combo are low 1st stage full boost by 2000 RPM, 2nd turbo by 4000-4500 rpm, and 25lb boost max with a redline around 7800-8000. I'd like to see 400-430rwhp. Turbo's are rated at 260hp each.

Just my 2penney worth,but with those heads and cam I think it will drop off at about 6500/6700rpm,have seen it on a similar combo with single turbo,the 86c would be more suitable with that desired refline,cheers richie,uk

iswinkels · Post by **iswinkels** » Fri Aug 17, 2007 4:02 pm

Yes your correct. I will be retarding the cam a few degrees to help compensate but I am expecting a cam change. The engine capacity is now 2443 as well, the compression is 7:1, and theres been other changes too as the project evolved.

richie,uk · Post by **richie,uk** » Fri Aug 17, 2007 5:02 pm

iswinkels wrote:Yes your correct. I will be retarding the cam a few degrees to help compensate but I am expecting a cam change. The engine capacity is now 2443 as well, the compression is 7:1, and theres been other changes too as the project evolved.

cheers richie,uk

eastcoastconversions · Fri Aug 17, 2007 6:43 pm

After reading all the great information on this stickey I am having second thoughts about my choice of cam. I am building a 1776 Turbo engine for a new buggy build. I don't plan on running the engine past 6000 or so rpm's. I am doing a draw through with a DHLA40 carb, 044 round port 40x35.5 heads, W110 cam with 1.25 rockers, low cr between 7:1 - 8:1 and running boost of about 10psi. I was hoping to get about 115hp and about the same number in torque.

I am thinking now that maybe I should get something like a TCS10 cam, same overall specs as the 110 cam but with the 112deg LC's. Do you guys think I would be better off going this route?

Thanks,
Jeff........

iswinkels · Post by **iswinkels** » Fri Aug 17, 2007 8:47 pm

Yes I agree with you. The TCS10 will max out around 6000. You will make around 120-135 rwhp depending on setup with what you've suggested there. Will be very drivable in traffic, retaining some manners so to speak.

MinamiKotaro · Post by **MinamiKotaro** » Fri Aug 17, 2007 8:51 pm

You can custom order a 110 on 112 or 114 lobes. The advantages of a TCS over a regular 110 or 120 are dubious.

The TCS-10 is actually a 110 on the intake and a 100 on the exhaust. It isn't just a 110 on wide lobes. The TCS-10 and -20 are primarily big torque cams, wonderful on the street and the occasional drag blast, but they have very little up top. I suspect you need very, very good heads to really make a TCS-10 or -20 work.

eastcoastconversions · Sat Aug 18, 2007 10:18 am

MinamiKotaro wrote:You can custom order a 110 on 112 or 114 lobes. The advantages of a TCS over a regular 110 or 120 are dubious.

The TCS-10 is actually a 110 on the intake and a 100 on the exhaust. It isn't just a 110 on wide lobes. The TCS-10 and -20 are primarily big torque cams, wonderful on the street and the occasional drag blast, but they have very little up top. I suspect you need very, very good heads to really make a TCS-10 or -20 work.

MinamiKotaro,

So if I read between the lines right are you saying that I am no better off using a TCS10 cam as opposed to a W110 cam?

I feel a little stupid, I had to look up the word "dubious" in the dictionary to understand the proper meaning.

Thanks,
Jeff.......

turbo_bob · Post by **turbo_bob** » Sat Aug 18, 2007 1:21 pm

I dont like the idea of a larger intake lift & duration and a smaller exhaust lift & duration on the same cam. It is backwards to my thought. If anything on a turbo engine you want the exhaust to flow and not be restricted.
So having the W 110 cam ordered in 112 LSA IMO would be better than the TCS-10 cam.

eastcoastconversions · Sat Aug 18, 2007 2:11 pm

turbo_bob wrote:I dont like the idea of a larger intake lift & duration and a smaller exhaust lift & duration on the same cam. It is backwards to my thought. If anything on a turbo engine you want the exhaust to flow and not be restricted.
So having the W 110 cam ordered in 112 LSA IMO would be better than the TCS-10 cam.

Sounds realistic! Do you order something like this from Engle or would it have to be custom built? I do have some time before I need it so it's not like I have to pull it out of stock somewhere.

Thanks,
Jeff.......

iswinkels · Post by **iswinkels** » Sat Aug 18, 2007 3:31 pm

aircooled.net will do custom grind web cams. I have no clue about anyone else.

MinamiKotaro · Post by **MinamiKotaro** » Sat Aug 18, 2007 8:13 pm

Yes, that is what I was saying. I'll be switching to a regular cam on 112 or 114 lobes with my next engine. Engle will custom grind you cams for around $120, last I checked.

CB will custom grind cams as well but you'll probably be waiting awhile to get it.

richie,uk · Post by **richie,uk** » Sun Aug 19, 2007 2:10 pm

eastcoastconversions wrote:
turbo_bob wrote:I dont like the idea of a larger intake lift & duration and a smaller exhaust lift & duration on the same cam. It is backwards to my thought. If anything on a turbo engine you want the exhaust to flow and not be restricted.
So having the W 110 cam ordered in 112 LSA IMO would be better than the TCS-10 cam.
Sounds realistic! Do you order something like this from Engle or would it have to be custom built? I do have some time before I need it so it's not like I have to pull it out of stock somewhere.

Thanks,
Jeff.......

Just call up Engle,they do it all the time,I have had seceral done,cheers richie,uk

Rich · Post by **Rich** » Tue Sep 11, 2007 3:21 pm

I'm running an 86b on 112 lobes on my 2276cc type 1. CR 7.9:1, 044 heads, 42x37 valves, 1.4 rockers.

Love this thread, very interesting

Thinking a little more compression and maybe an 86c would be even more fun though

Soul · Post by **Soul** » Tue Dec 04, 2007 4:20 pm

turbo_bob wrote:I dont like the idea of a larger intake lift & duration and a smaller exhaust lift & duration on the same cam. It is backwards to my thought. If anything on a turbo engine you want the exhaust to flow and not be restricted.
So having the W 110 cam ordered in 112 LSA IMO would be better than the TCS-10 cam.

I agree with Turbo Bob's logic however, I was bench racing with some buddies and they claim for AA applications you would want to port the heads so the exhaust would actually out flow the intakes. You would then control the exhaust flow with the smaller lift of the cam.

Does anyone have any thoughts on this approach?